Ignore v3 metadata members declaring must_understand: false - #94

Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom
konstibob:fix/must-understand-extra-fields
Open

Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom
konstibob:fix/must-understand-extra-fields

Conversation

@konstibob

@konstibobkonstibob commented Aug 27, 2026

Copy link
Copy Markdown
Contributor

A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.

Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.

must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.

Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.

@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob
, '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
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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('^' + ".*" + '

Skip to content
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob

, '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); }
})();
})();

Skip to content
Ignore v3 metadata members declaring must_understand: false - #94
Open
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Open
Ignore v3 metadata members declaring must_understand: false#94
konstibob wants to merge 1 commit into
zarr-developers:mainfrom 
konstibob:fix/must-understand-extra-fields
Conversation
@konstibob
@konstibobkonstibob
commented
Aug 27, 2026

Copy link


Copy Markdown

Contributor
A Zarr v3 writer may add members to a metadata document that a reader does not know about. When such a member is a JSON object carrying "must_understand": false, the specification requires a reader to ignore it; any other unknown member has to be rejected, because it may change how the array is to be interpreted.
Reading a zarr.json written by a newer implementation therefore failed with an UnrecognizedPropertyException on a member that was explicitly marked as safe to skip.
must_understand deliberately does not apply to codec, chunk grid or chunk key encoding names: a codec cannot be skipped and still leave the chunk bytes decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes with an extra field now opens, and a document zarr-java rewrites is read back by zarr-python with the field intact in its own extra_fields.
@konstibob@claude
Ignore v3 metadata members declaring must_understand: false
8697775
A Zarr v3 writer may add members to a metadata document that a reader does
not know about. When such a member is a JSON object carrying
"must_understand": false, the specification requires a reader to ignore it;
any other unknown member has to be rejected, because it may change how the
array is to be interpreted.
zarr-java rejected every unknown member instead, because the ObjectMapper in
v3.Node was built with Jackson's default FAIL_ON_UNKNOWN_PROPERTIES. Reading
a zarr.json written by a newer implementation therefore failed with an
UnrecognizedPropertyException on a member that was explicitly marked as safe
to skip.
Unknown members are now collected through a @JsonAnySetter creator parameter
and validated in ExtraFields, which mirrors zarr-python 3.1.6
(zarr/core/metadata/v3.py):
- a JSON object with "must_understand": false is ignored,
- anything else is rejected with a ZarrException,
- an extra field colliding with a member the document defines itself is
rejected.
Ignored members are kept on the metadata and written back out by a
@JsonAnyGetter, so that another implementation's extension survives a
metadata rewrite. ArrayMetadataBuilder.fromArrayMetadata and
Group.setAttributes carry them over, which covers resize, setAttributes and
updateAttributes.
must_understand deliberately does not apply to codec, chunk grid or chunk key
encoding names: a codec cannot be skipped and still leave the chunk bytes
decodable, so an unknown name there still fails.
Verified against zarr-python 3.1.6 in both directions: a document it writes
with an extra field now opens, and a document zarr-java rewrites is read back
by zarr-python with the field intact in its own extra_fields.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment

Reviewers


No reviews


Assignees


No one assigned


Labels


None yet


Projects


None yet


Milestone


No milestone


Development

Successfully merging this pull request may close these issues.

1 participant

@konstibob