feat: transparent leader hint reconnect on consume#2

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Merged
vieiralucas merged 3 commits into from
Mar 24, 2026
Merged

feat: transparent leader hint reconnect on consume #2

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f7a4ed9
feat: transparent leader hint reconnect on consume
vieiralucas Mar 22, 2026
1f5753e
fix: close old grpc channel before reconnecting
vieiralucas Mar 24, 2026
273746e
fix: resolve mypy no-any-return errors
vieiralucas Mar 24, 2026
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73 changes: 59 additions & 14 deletions fila/async_client.py
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
"""Return the leader address from trailing metadata, if present."""
if err.code() != grpc.StatusCode.UNAVAILABLE:
return None
trailing = err.trailing_metadata()
if trailing is None:
return None
for key, value in trailing:
if key == _LEADER_HINT_KEY:
return str(value)
return None


class AsyncClient:
"""Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
api_key: API key for authentication. When set, every RPC includes an
``authorization: Bearer <key>`` metadata header.
"""
use_tls = tls or ca_cert is not None
self._tls = tls
self._ca_cert = ca_cert
self._client_cert = client_cert
self._client_key = client_key
self._api_key = api_key

use_tls = tls or ca_cert is not None
if (client_cert is not None or client_key is not None) and not use_tls:
raise ValueError(
"client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
)

self._channel = self._make_channel(addr)
self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

def _make_channel(self, addr: str) -> grpc.aio.Channel:
"""Create an async gRPC channel to the given address using stored credentials."""
use_tls = self._tls or self._ca_cert is not None

interceptors: list[grpc.aio.ClientInterceptor] = []
if api_key is not None:
interceptors.append(_AsyncApiKeyInterceptor(api_key))
if self._api_key is not None:
interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

if use_tls:
creds = grpc.ssl_channel_credentials(
root_certificates=ca_cert,
private_key=client_key,
certificate_chain=client_cert,
root_certificates=self._ca_cert,
private_key=self._client_key,
certificate_chain=self._client_cert,
)
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
addr, creds, interceptors=interceptors or None
)
else:
self._channel = grpc.aio.insecure_channel(
addr, interceptors=interceptors or None
)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return grpc.aio.insecure_channel(
addr, interceptors=interceptors or None
)

async def close(self) -> None:
"""Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
server stream closes or an error occurs. Nil message frames (keepalive
signals) are skipped automatically.

If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
trailing metadata entry, the client transparently reconnects to the
leader address and retries the consume call once.

Args:
queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
service_pb2.ConsumeRequest(queue=queue)
)
except grpc.RpcError as e:
raise _map_consume_error(e) from e
leader_addr = _extract_leader_hint(e)
if leader_addr is not None:
stream = await self._reconnect_and_consume(leader_addr, queue)
else:
raise _map_consume_error(e) from e

return self._consume_iter(stream)

async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
"""Create a new channel to *leader_addr* and retry the consume call."""
await self._channel.close()
self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.
self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
try:
return self._stub.Consume(
service_pb2.ConsumeRequest(queue=queue)
)
except grpc.RpcError as e:
raise _map_consume_error(e) from e

async def _consume_iter(
self,
stream: Any,
Expand Down
73 changes: 62 additions & 11 deletions fila/client.py
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
"""Return the leader address from trailing metadata, if present.

The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
UNAVAILABLE status when the node is not the leader for the requested queue.
"""
if err.code() != grpc.StatusCode.UNAVAILABLE:
return None
trailing = err.trailing_metadata()
if trailing is None:
return None
for key, value in trailing:
if key == _LEADER_HINT_KEY:
return str(value)
return None


class _ClientCallDetails(
grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
api_key: API key for authentication. When set, every RPC includes an
``authorization: Bearer <key>`` metadata header.
"""
use_tls = tls or ca_cert is not None
self._tls = tls
self._ca_cert = ca_cert
self._client_cert = client_cert
self._client_key = client_key
self._api_key = api_key

use_tls = tls or ca_cert is not None
if (client_cert is not None or client_key is not None) and not use_tls:
raise ValueError(
"client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
)

self._channel = self._make_channel(addr)
self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

def _make_channel(self, addr: str) -> grpc.Channel:
"""Create a gRPC channel to the given address using stored credentials."""
use_tls = self._tls or self._ca_cert is not None

if use_tls:
creds = grpc.ssl_channel_credentials(
root_certificates=ca_cert,
private_key=client_key,
certificate_chain=client_cert,
root_certificates=self._ca_cert,
private_key=self._client_key,
certificate_chain=self._client_cert,
)
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

if api_key is not None:
interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
if self._api_key is not None:
interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

def close(self) -> None:
"""Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
server stream closes or an error occurs. Skip nil message frames
(keepalive signals) automatically.

If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
trailing metadata entry, the client transparently reconnects to the
leader address and retries the consume call once.

Args:
queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
service_pb2.ConsumeRequest(queue=queue)
)
except grpc.RpcError as e:
raise _map_consume_error(e) from e
leader_addr = _extract_leader_hint(e)
if leader_addr is not None:
stream = self._reconnect_and_consume(leader_addr, queue)
else:
raise _map_consume_error(e) from e

return self._consume_iter(stream)

def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
"""Create a new channel to *leader_addr* and retry the consume call."""
self._channel.close()
self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.
self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
try:
return self._stub.Consume(
service_pb2.ConsumeRequest(queue=queue)
)
except grpc.RpcError as e:
raise _map_consume_error(e) from e

def _consume_iter(
self,
stream: Any,
Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
feat: transparent leader hint reconnect on consume#2

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to your account

 Merged

vieiralucas
merged 3 commits into

from

Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
feat: transparent leader hint reconnect on consume#2

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

vieiralucas
merged 3 commits into

from

Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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3 commits


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Hold shift + click to select a range
f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
feat: transparent leader hint reconnect on consume#2

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 Merged

vieiralucas
merged 3 commits into

from

Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
feat: transparent leader hint reconnect on consume#2

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

vieiralucas
merged 3 commits into

from

Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
Show file tree
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3 commits


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Hold shift + click to select a range
f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

File filter

Filter by extension
Filter by extension
Conversations

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Loading
Jump to

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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feat: transparent leader hint reconnect on consume#2

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 Merged

vieiralucas
merged 3 commits into

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Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
feat: transparent leader hint reconnect on consume#2

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
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to your account

 Merged

vieiralucas
merged 3 commits into

from

Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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 Merged

vieiralucas
merged 3 commits into

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Mar 24, 2026
 Merged


feat: transparent leader hint reconnect on consume
#2
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f7a4ed9

feat: transparent leader hint reconnect on consume


vieiralucas Mar 22, 2026
1f5753e

fix: close old grpc channel before reconnecting


vieiralucas Mar 24, 2026
273746e

fix: resolve mypy no-any-return errors


vieiralucas Mar 24, 2026

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73 changes: 59 additions & 14 deletions
fila/async_client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -99,6 +99,22 @@ async def intercept_unary_stream(
 return await continuation(new_details, request)


_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present."""
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class AsyncClient:
 """Asynchronous client for the Fila message broker.

Expand DownExpand Up@@ -162,32 +178,41 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.aio.Channel:
 """Create an async gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 interceptors: list[grpc.aio.ClientInterceptor] = []
 if api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(api_key))
 if self._api_key is not None:
 interceptors.append(_AsyncApiKeyInterceptor(self._api_key))

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.aio.secure_channel(
return grpc.aio.secure_channel(
 addr, creds, interceptors=interceptors or None
 )
 else:
 self._channel = grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 return grpc.aio.insecure_channel(
 addr, interceptors=interceptors or None
 )

 async def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -238,6 +263,10 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 server stream closes or an error occurs. Nil message frames (keepalive
 signals) are skipped automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -253,10 +282,26 @@ async def consume(self, queue: str) -> AsyncIterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = await self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 async def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 await self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 async def _consume_iter(
 self,
 stream: Any,
Expand Down

73 changes: 62 additions & 11 deletions
fila/client.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -13,6 +13,25 @@
if TYPE_CHECKING:
 from collections.abc import Iterator

_LEADER_HINT_KEY = "x-fila-leader-addr"


def _extract_leader_hint(err: grpc.RpcError) -> str | None:
 """Return the leader address from trailing metadata, if present.

 The server sets ``x-fila-leader-addr`` in trailing metadata alongside an
 UNAVAILABLE status when the node is not the leader for the requested queue.
 """
 if err.code() != grpc.StatusCode.UNAVAILABLE:
 return None
 trailing = err.trailing_metadata()
 if trailing is None:
 return None
 for key, value in trailing:
 if key == _LEADER_HINT_KEY:
 return str(value)
 return None


class _ClientCallDetails(
 grpc.ClientCallDetails, # type: ignore[misc]
Expand DownExpand Up@@ -143,28 +162,40 @@ def __init__(
 api_key: API key for authentication. When set, every RPC includes an
 ``authorization: Bearer <key>`` metadata header.
 """
 use_tls = tls or ca_cert is not None
 self._tls = tls
 self._ca_cert = ca_cert
 self._client_cert = client_cert
 self._client_key = client_key
 self._api_key = api_key

 use_tls = tls or ca_cert is not None
 if (client_cert is not None or client_key is not None) and not use_tls:
 raise ValueError(
 "client_cert and client_key require ca_cert or tls=True to establish a TLS channel"
 )

 self._channel = self._make_channel(addr)
 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]

 def _make_channel(self, addr: str) -> grpc.Channel:
 """Create a gRPC channel to the given address using stored credentials."""
 use_tls = self._tls or self._ca_cert is not None

 if use_tls:
 creds = grpc.ssl_channel_credentials(
 root_certificates=ca_cert,
 private_key=client_key,
 certificate_chain=client_cert,
 root_certificates=self._ca_cert,
 private_key=self._client_key,
 certificate_chain=self._client_cert,
 )
self._channel = grpc.secure_channel(addr, creds)
channel: grpc.Channel = grpc.secure_channel(addr, creds)
 else:
self._channel = grpc.insecure_channel(addr)
channel = grpc.insecure_channel(addr)

 if api_key is not None:
 interceptor = _ApiKeyInterceptor(api_key)
self._channel = grpc.intercept_channel(self._channel, interceptor)
 if self._api_key is not None:
 interceptor = _ApiKeyInterceptor(self._api_key)
channel = grpc.intercept_channel(channel, interceptor)

self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
return channel

 def close(self) -> None:
 """Close the underlying gRPC channel."""
Expand DownExpand Up@@ -215,6 +246,10 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 server stream closes or an error occurs. Skip nil message frames
 (keepalive signals) automatically.

 If the server returns UNAVAILABLE with an ``x-fila-leader-addr``
 trailing metadata entry, the client transparently reconnects to the
 leader address and retries the consume call once.

 Args:
 queue: Queue to consume from.

Expand All@@ -230,10 +265,26 @@ def consume(self, queue: str) -> Iterator[ConsumeMessage]:
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e
 leader_addr = _extract_leader_hint(e)
 if leader_addr is not None:
 stream = self._reconnect_and_consume(leader_addr, queue)
 else:
 raise _map_consume_error(e) from e

 return self._consume_iter(stream)

 def _reconnect_and_consume(self, leader_addr: str, queue: str) -> Any:
 """Create a new channel to *leader_addr* and retry the consume call."""
 self._channel.close()
 self._channel = self._make_channel(leader_addr)
Comment thread
cubic-dev-ai[bot] marked this conversation as resolved.

 self._stub = service_pb2_grpc.FilaServiceStub(self._channel) # type: ignore[no-untyped-call]
 try:
 return self._stub.Consume(
 service_pb2.ConsumeRequest(queue=queue)
 )
 except grpc.RpcError as e:
 raise _map_consume_error(e) from e

 def _consume_iter(
 self,
 stream: Any,
Expand Down
Loading