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bpo-26175: Fix SpooledTemporaryFile IOBase abstract - #3249
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One would assume that this class implements the IOBase abstract. As the underlying file-like object is either io.BytesIO, io.StringIO, or a true file object, this is a reasonable abstract expect and to implement. Regardless, the behaviour of this class does not change much in the case of the attribute being missing from the underlying file-like; an AttributeError is still raised, albeit from one additional frame on the stack trace.
the-knights-who-say-ni
commented
Aug 30, 2017
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merwok
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Patch looks good! Note that the bug contains a stronger motivation than the first mssage here: «This was discovered when seeking a SpooledTemporaryFile-backed lzma file.»
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bedevere-bot
commented
Sep 20, 2017
A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated. Once you have made the requested changes, please leave a comment on this pull request containing the phrase |
GFernie
commented
Sep 30, 2017
Thanks for the feedback @merwok I've made some changes to more accurately test how SpooledTemporaryFile implements IOBase. So, there are now two separate tests:
From the IOBase docs:
I didn't expect the Spanish Inquisition! |
bedevere-bot
commented
Sep 30, 2017
Nobody expects the Spanish Inquisition! @merwok: please review the changes made to this pull request. |
embe
commented
Feb 19, 2018
There is at least one more incompatibility with |
| def __iter__(self): | ||
| return self._file.__iter__() | ||
| def __del__(self): |
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This shouldn't be added: deleting the SpooledTemporaryFile will null out the reference to the underline file, and therefor call its __del__
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I think if you inherit the default IOBase.__del__ implementation, it will call close and defeat any ResourceWarning that might otherwise be emitted. Perhaps it is better to make __del__ do nothing, or set it to . [Seems that last option doesn’t exist.]object.__del__
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I agree: the underlying file should not be explicitly deleted as this is not expected behaviour. I can imagine a situation where someone is deliberately holding a reference to the underlying file and they would not expect/want it to be closed until their own reference has fallen out of scope. I've changed the method to do nothing and added a docstring to reflect this.
Thanks for your feedback
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I agree: the underlying file should not be explicitly deleted as this is not expected behaviour
The doc says: """This function operates exactly as TemporaryFile() does, except [irrelevant differences]."""
And then, about TemporaryFile: """On completion of the context or destruction of the file object the temporary file will be removed from the filesystem."""
So it seems the underlying file should be deleted when the file object disappears.
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The point is that IOBase implements a __del__ which has some side-effects. Those side effects are not desirable here. Any underlying buffers being wrapped, e.g. the TemporaryFile or the BytesIO, will be gc'd and handled as they should.
I think this implementation is correct.
We don't want to delete the underlying file explicitly as the expected behaviour is for the file to be deleted *after* it falls out of scope.
You are right, @embe; it's part of the interface: The method now returns the value returned from Thanks for pointing this out |
GFernie
commented
Sep 9, 2018
Re seek: I've also done the same with This is also part of the file interface: |
csabella
commented
Jan 12, 2020
| if size is None: | ||
| self._file.truncate() | ||
| return self._file.truncate() | ||
| else: |
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this else is not needed, PEP warning, might as well fix
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It's not necessary to remove the else. It does no harm.
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I never said it was necessary, just bad style as it unnecessarily increased the code depth, take my comment as an FYI
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Just wanted to confirm @merwok - nothing needs to be changed here for approval?
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Right, I advise to not change the else line.
danieldjewell
commented
May 13, 2020
merwok
commented
May 13, 2020
This PR needs to merge master and address Antoine’s latest review. |
csabella
commented
May 23, 2020
@danieldjewell, you're right. Would you like to create a new PR based on this one? If so, please follow this section of the devguide to give GFernie the credit as the original author. Thanks! |
carlos-jenkins
commented
Oct 31, 2020
Hello, For anyone that got here looking for the error In my case it was trying to pass an In one of your modules: fromtempfileimportSpooledTemporaryFiledef_seekable(self):
""" Monkey patched seekable() method for the SpooledTemporaryFile class. Sadly, we cannot send an instance of the SpooledTemporaryFile to the ZipFile object. This is because the SpooledTemporaryFile doesn't inherit / implement the IOBase class. This bug is reported in CPython: https://bugs.python.org/issue26175 And an unmerged PR is located here: https://github.com/python/cpython/pull/3249/files In Python 3.8, attempting to pass the tmpfd fails with: AttributeError: 'SpooledTemporaryFile' object has no attribute 'seekable' So, the workaround to avoid copying the file is to monkey patch the class and add the missing method. Sorry. """returnself._file.seekable()
SpooledTemporaryFile.seekable=_seekable |
Molaire
commented
Jan 18, 2021
To Google people: this also breaks pandas.read_csv() and this monkey patch can be used for property readable writable and seekable to fix it.
|
MikeEcho
commented
Dec 26, 2021
Python dev here from the future (2021 - save yourselves while you can). Still getting |
pR0Ps
commented
Dec 31, 2021
This PR is stale because it has been open for 30 days with no activity. |
methane
commented
May 3, 2022
Close this because I merged #29560. |
Version 0.15.2 - Rule code generation uses a filename that coverage will ignore. The previous value, "generated", was causing coverage to fail. - The test client removes the cookie header if there are no persisted cookies. This fixes an issue introduced in 0.15.0 where the cookies from the original request were used for redirects, causing functions such as logout to fail. - The test client copies the environ before passing it to the app, to prevent in-place modifications from affecting redirect requests. - The "werkzeug" logger only adds a handler if there is no handler configured for its level in the logging chain. This avoids double logging if other code configures logging first. Version 0.15.1 - :class:~exceptions.Unauthorized takes description as the first argument, restoring previous behavior. The new www_authenticate argument is listed second. Version 0.15.0 - Building URLs is ~7x faster. Each :class:~routing.Rule compiles an optimized function for building itself. - :meth:MapAdapter.build() <routing.MapAdapter.build> can be passed a :class:~datastructures.MultiDict to represent multiple values for a key. It already did this when passing a dict with a list value. - path_info defaults to '/' for :meth:Map.bind() <routing.Map.bind>. :pr:1316) - Change RequestRedirect code from 301 to 308, preserving the verb and request body (form data) during redirect. - int and float converters in URL rules will handle negative values if passed the signed=True parameter. For example, /jump/<int(signed=True):count>. - Location autocorrection in :func:Response.get_wsgi_headers() <wrappers.BaseResponse.get_wsgi_headers> is relative to the current path rather than the root path. :pr:1315) - 412 responses once again include entity headers and an error message in the body. They were originally omitted when implementing If-Match - The Content-Length header is removed for 1xx and 204 responses. This fixes a previous change where no body would be sent, but the header would still be present. The new behavior matches RFC 7230. - :class:~exceptions.Unauthorized takes a www_authenticate parameter to set the WWW-Authenticate header for the response, which is technically required for a valid 401 response. - Add support for status code 424 :exc:~exceptions.FailedDependency. - :func:http.parse_cookie ignores empty segments rather than producing a cookie with no key or value. - :func:~http.parse_authorization_header (and :class:~datastructures.Authorization, :attr:~wrappers.Request.authorization) treats the authorization header as UTF-8. On Python 2, basic auth username and password are unicode. - :func:~http.parse_options_header understands :rfc:2231 parameter continuations. - :func:~urls.uri_to_iri does not unquote ASCII characters in the unreserved class, such as space, and leaves invalid bytes quoted when decoding. :func:~urls.iri_to_uri does not quote reserved characters. See :rfc:3987 for these character classes. - get_content_type appends a charset for any mimetype that ends with +xml, not just those that start with application/. Known text types such as application/javascript are also given charsets. - Clean up werkzeug.security module, remove outdated hashlib support. - In :func:~security.generate_password_hash, PBKDF2 uses 150000 iterations by default, increased from 50000. - :class:~wsgi.ClosingIterator calls close on the wrapped *iterable*, not the internal iterator. This doesn't affect objects where __iter__ returned self. For other objects, the method was not called before. - Bytes may be used as keys in :class:~datastructures.Headers, they will be decoded as Latin-1 like values are. - :class:~datastructures.Range validates that list of range tuples passed to it would produce a valid Range header. - :class:~datastructures.FileStorage looks up attributes on stream._file if they don't exist on stream, working around an issue where :func:tempfile.SpooledTemporaryFile didn't implement all of :class:io.IOBase. See python/cpython#3249. - :class:CombinedMultiDict.copy() <datastructures.CombinedMultiDict> returns a shallow mutable copy as a :class:~datastructures.MultiDict. The copy no longer reflects changes to the combined dicts, but is more generally useful. - The version of jQuery used by the debugger is updated to 3.3.1. - The debugger correctly renders long markupsafe.Markup instances. - The debugger can serve resources when Werkzeug is installed as a zip file. DebuggedApplication.get_resource uses pkgutil.get_data. - The debugger and server log support Python 3's chained exceptions. - The interactive debugger highlights frames that come from user code to make them easy to pick out in a long stack trace. Note that if an env was created with virtualenv instead of venv, the debugger may incorrectly classify some frames. - Clicking the error message at the top of the interactive debugger will jump down to the bottom of the traceback. - When generating a PIN, the debugger will ignore a KeyError raised when the current UID doesn't have an associated username, which can happen in Docker. - :class:~exceptions.BadRequestKeyError adds the KeyError message to the description, making it clearer what caused the 400 error. Frameworks like Flask can omit this information in production by setting e.args = (). - If a nested ImportError occurs from :func:~utils.import_string the traceback mentions the nested import. Removes an untested code path for handling "modules not yet set up by the parent." - Triggering a reload while using a tool such as PDB no longer hides input. - The reloader will not prepend the Python executable to the command line if the Python file is marked executable. This allows the reloader to work on NixOS. - Fix an issue where sys.path would change between reloads when running with python -m app. The reloader can detect that a module was run with "-m" and reconstructs that instead of the file path in sys.argv when reloading. - The dev server can bind to a Unix socket by passing a hostname like unix://app.socket. - Server uses IPPROTO_TCP constant instead of SOL_TCP for Jython compatibility. - When using an adhoc SSL cert with :func:~serving.run_simple, the cert is shown as self-signed rather than signed by an invalid authority. - The development server logs the unquoted IRI rather than the raw request line, to make it easier to work with Unicode in request paths during development. - The development server recognizes ConnectionError on Python 3 to silence client disconnects, and does not silence other OSErrors that may have been raised inside the application. - The environ keys REQUEST_URI and RAW_URI contain the raw path before it was percent-decoded. This is non-standard, but many WSGI servers add them. Middleware could replace PATH_INFO with this to route based on the raw value. - :class:~test.EnvironBuilder doesn't set CONTENT_TYPE or CONTENT_LENGTH in the environ if they aren't set. Previously these used default values if they weren't set. Now it's possible to distinguish between empty and unset values. - The test client raises a ValueError if a query string argument would overwrite a query string in the path. - :class:test.EnvironBuilder and :class:test.Client take a json argument instead of manually passing data and content_type. This is serialized using the :meth:test.EnvironBuilder.json_dumps method. - :class:test.Client redirect handling is rewritten. - The redirect environ is copied from the initial request environ. - Script root and path are correctly distinguished when redirecting to a path under the root. - The HEAD method is not changed to GET. - 307 and 308 codes preserve the method and body. All others ignore the body and related headers. - Headers are passed to the new request for all codes, following what browsers do. - :class:test.EnvironBuilder sets the content type and length headers in addition to the WSGI keys when detecting them from the data. - Intermediate response bodies are iterated over even when buffered=False to ensure iterator middleware can run cleanup code safely. Only the last response is not buffered. - :class:~test.EnvironBuilder, :class:~datastructures.FileStorage, and :func:wsgi.get_input_stream no longer share a global _empty_stream instance. This improves test isolation by preventing cases where closing the stream in one request would affect other usages. - The default :attr:SecureCookie.serialization_method <contrib.securecookie.SecureCookie.serialization_method> will change from :mod:pickle to :mod:json in 1.0. To upgrade existing tokens, override :meth:~contrib.securecookie.SecureCookie.unquote to try pickle if json fails. - CGIRootFix no longer modifies PATH_INFO for very old versions of Lighttpd. LighttpdCGIRootFix was renamed to CGIRootFix in 0.9. Both are deprecated and will be removed in version 1.0. - :class:werkzeug.wrappers.json.JSONMixin has been replaced with Flask's implementation. Check the docs for the full API. - The :doc:contrib modules </contrib/index> are deprecated and will either be moved into werkzeug core or removed completely in version 1.0. Some modules that already issued deprecation warnings have been removed. Be sure to run or test your code with python -W default::DeprecationWarning to catch any deprecated code you're using. - LintMiddleware has moved to :mod:werkzeug.middleware.lint. - ProfilerMiddleware has moved to :mod:werkzeug.middleware.profiler. - ProxyFix has moved to :mod:werkzeug.middleware.proxy_fix. - JSONRequestMixin has moved to :mod:werkzeug.wrappers.json. - cache has been extracted into a separate project, cachelib <https://github.com/pallets/cachelib>_. The version in Werkzeug is deprecated. - securecookie and sessions have been extracted into a separate project, secure-cookie <https://github.com/pallets/secure-cookie>_. The version in Werkzeug is deprecated. - Everything in fixers, except ProxyFix, is deprecated. - Everything in wrappers, except JSONMixin, is deprecated. - atom is deprecated. This did not fit in with the rest of Werkzeug, and is better served by a dedicated library in the community. - jsrouting is removed. Set URLs when rendering templates or JSON responses instead. - limiter is removed. Its specific use is handled by Werkzeug directly, but stream limiting is better handled by the WSGI server in general. - testtools is removed. It did not offer significant benefit over the default test client. - iterio is deprecated. - :func:wsgi.get_host no longer looks at X-Forwarded-For. Use :class:~middleware.proxy_fix.ProxyFix to handle that. - :class:~middleware.proxy_fix.ProxyFix is refactored to support more headers, multiple values, and more secure configuration. - Each header supports multiple values. The trusted number of proxies is configured separately for each header. The num_proxies argument is deprecated. - Sets SERVER_NAME and SERVER_PORT based on X-Forwarded-Host. - Sets SERVER_PORT and modifies HTTP_HOST based on X-Forwarded-Port. - Sets SCRIPT_NAME based on X-Forwarded-Prefix. - The original WSGI environment values are stored in the werkzeug.proxy_fix.orig key, a dict. The individual keys werkzeug.proxy_fix.orig_remote_addr, werkzeug.proxy_fix.orig_wsgi_url_scheme, and werkzeug.proxy_fix.orig_http_host are deprecated. - Middleware from werkzeug.wsgi has moved to separate modules under werkzeug.middleware, along with the middleware moved from werkzeug.contrib. The old werkzeug.wsgi imports are deprecated and will be removed in version 1.0. - werkzeug.wsgi.DispatcherMiddleware has moved to :class:werkzeug.middleware.dispatcher.DispatcherMiddleware. - werkzeug.wsgi.ProxyMiddleware as moved to :class:werkzeug.middleware.http_proxy.ProxyMiddleware. - werkzeug.wsgi.SharedDataMiddleware has moved to :class:werkzeug.middleware.shared_data.SharedDataMiddleware. - :class:~middleware.http_proxy.ProxyMiddleware proxies the query string. - The filenames generated by :class:~middleware.profiler.ProfilerMiddleware can be customized. - The werkzeug.wrappers module has been converted to a package, and its various classes have been organized into separate modules. Any previously documented classes, understood to be the existing public API, are still importable from werkzeug.wrappers, or may be imported from their specific modules.
Version 0.15.2 - Rule code generation uses a filename that coverage will ignore. The previous value, "generated", was causing coverage to fail. - The test client removes the cookie header if there are no persisted cookies. This fixes an issue introduced in 0.15.0 where the cookies from the original request were used for redirects, causing functions such as logout to fail. - The test client copies the environ before passing it to the app, to prevent in-place modifications from affecting redirect requests. - The "werkzeug" logger only adds a handler if there is no handler configured for its level in the logging chain. This avoids double logging if other code configures logging first. Version 0.15.1 - :class:~exceptions.Unauthorized takes description as the first argument, restoring previous behavior. The new www_authenticate argument is listed second. Version 0.15.0 - Building URLs is ~7x faster. Each :class:~routing.Rule compiles an optimized function for building itself. - :meth:MapAdapter.build() <routing.MapAdapter.build> can be passed a :class:~datastructures.MultiDict to represent multiple values for a key. It already did this when passing a dict with a list value. - path_info defaults to '/' for :meth:Map.bind() <routing.Map.bind>. :pr:1316) - Change RequestRedirect code from 301 to 308, preserving the verb and request body (form data) during redirect. - int and float converters in URL rules will handle negative values if passed the signed=True parameter. For example, /jump/<int(signed=True):count>. - Location autocorrection in :func:Response.get_wsgi_headers() <wrappers.BaseResponse.get_wsgi_headers> is relative to the current path rather than the root path. :pr:1315) - 412 responses once again include entity headers and an error message in the body. They were originally omitted when implementing If-Match - The Content-Length header is removed for 1xx and 204 responses. This fixes a previous change where no body would be sent, but the header would still be present. The new behavior matches RFC 7230. - :class:~exceptions.Unauthorized takes a www_authenticate parameter to set the WWW-Authenticate header for the response, which is technically required for a valid 401 response. - Add support for status code 424 :exc:~exceptions.FailedDependency. - :func:http.parse_cookie ignores empty segments rather than producing a cookie with no key or value. - :func:~http.parse_authorization_header (and :class:~datastructures.Authorization, :attr:~wrappers.Request.authorization) treats the authorization header as UTF-8. On Python 2, basic auth username and password are unicode. - :func:~http.parse_options_header understands :rfc:2231 parameter continuations. - :func:~urls.uri_to_iri does not unquote ASCII characters in the unreserved class, such as space, and leaves invalid bytes quoted when decoding. :func:~urls.iri_to_uri does not quote reserved characters. See :rfc:3987 for these character classes. - get_content_type appends a charset for any mimetype that ends with +xml, not just those that start with application/. Known text types such as application/javascript are also given charsets. - Clean up werkzeug.security module, remove outdated hashlib support. - In :func:~security.generate_password_hash, PBKDF2 uses 150000 iterations by default, increased from 50000. - :class:~wsgi.ClosingIterator calls close on the wrapped *iterable*, not the internal iterator. This doesn't affect objects where __iter__ returned self. For other objects, the method was not called before. - Bytes may be used as keys in :class:~datastructures.Headers, they will be decoded as Latin-1 like values are. - :class:~datastructures.Range validates that list of range tuples passed to it would produce a valid Range header. - :class:~datastructures.FileStorage looks up attributes on stream._file if they don't exist on stream, working around an issue where :func:tempfile.SpooledTemporaryFile didn't implement all of :class:io.IOBase. See python/cpython#3249. - :class:CombinedMultiDict.copy() <datastructures.CombinedMultiDict> returns a shallow mutable copy as a :class:~datastructures.MultiDict. The copy no longer reflects changes to the combined dicts, but is more generally useful. - The version of jQuery used by the debugger is updated to 3.3.1. - The debugger correctly renders long markupsafe.Markup instances. - The debugger can serve resources when Werkzeug is installed as a zip file. DebuggedApplication.get_resource uses pkgutil.get_data. - The debugger and server log support Python 3's chained exceptions. - The interactive debugger highlights frames that come from user code to make them easy to pick out in a long stack trace. Note that if an env was created with virtualenv instead of venv, the debugger may incorrectly classify some frames. - Clicking the error message at the top of the interactive debugger will jump down to the bottom of the traceback. - When generating a PIN, the debugger will ignore a KeyError raised when the current UID doesn't have an associated username, which can happen in Docker. - :class:~exceptions.BadRequestKeyError adds the KeyError message to the description, making it clearer what caused the 400 error. Frameworks like Flask can omit this information in production by setting e.args = (). - If a nested ImportError occurs from :func:~utils.import_string the traceback mentions the nested import. Removes an untested code path for handling "modules not yet set up by the parent." - Triggering a reload while using a tool such as PDB no longer hides input. - The reloader will not prepend the Python executable to the command line if the Python file is marked executable. This allows the reloader to work on NixOS. - Fix an issue where sys.path would change between reloads when running with python -m app. The reloader can detect that a module was run with "-m" and reconstructs that instead of the file path in sys.argv when reloading. - The dev server can bind to a Unix socket by passing a hostname like unix://app.socket. - Server uses IPPROTO_TCP constant instead of SOL_TCP for Jython compatibility. - When using an adhoc SSL cert with :func:~serving.run_simple, the cert is shown as self-signed rather than signed by an invalid authority. - The development server logs the unquoted IRI rather than the raw request line, to make it easier to work with Unicode in request paths during development. - The development server recognizes ConnectionError on Python 3 to silence client disconnects, and does not silence other OSErrors that may have been raised inside the application. - The environ keys REQUEST_URI and RAW_URI contain the raw path before it was percent-decoded. This is non-standard, but many WSGI servers add them. Middleware could replace PATH_INFO with this to route based on the raw value. - :class:~test.EnvironBuilder doesn't set CONTENT_TYPE or CONTENT_LENGTH in the environ if they aren't set. Previously these used default values if they weren't set. Now it's possible to distinguish between empty and unset values. - The test client raises a ValueError if a query string argument would overwrite a query string in the path. - :class:test.EnvironBuilder and :class:test.Client take a json argument instead of manually passing data and content_type. This is serialized using the :meth:test.EnvironBuilder.json_dumps method. - :class:test.Client redirect handling is rewritten. - The redirect environ is copied from the initial request environ. - Script root and path are correctly distinguished when redirecting to a path under the root. - The HEAD method is not changed to GET. - 307 and 308 codes preserve the method and body. All others ignore the body and related headers. - Headers are passed to the new request for all codes, following what browsers do. - :class:test.EnvironBuilder sets the content type and length headers in addition to the WSGI keys when detecting them from the data. - Intermediate response bodies are iterated over even when buffered=False to ensure iterator middleware can run cleanup code safely. Only the last response is not buffered. - :class:~test.EnvironBuilder, :class:~datastructures.FileStorage, and :func:wsgi.get_input_stream no longer share a global _empty_stream instance. This improves test isolation by preventing cases where closing the stream in one request would affect other usages. - The default :attr:SecureCookie.serialization_method <contrib.securecookie.SecureCookie.serialization_method> will change from :mod:pickle to :mod:json in 1.0. To upgrade existing tokens, override :meth:~contrib.securecookie.SecureCookie.unquote to try pickle if json fails. - CGIRootFix no longer modifies PATH_INFO for very old versions of Lighttpd. LighttpdCGIRootFix was renamed to CGIRootFix in 0.9. Both are deprecated and will be removed in version 1.0. - :class:werkzeug.wrappers.json.JSONMixin has been replaced with Flask's implementation. Check the docs for the full API. - The :doc:contrib modules </contrib/index> are deprecated and will either be moved into werkzeug core or removed completely in version 1.0. Some modules that already issued deprecation warnings have been removed. Be sure to run or test your code with python -W default::DeprecationWarning to catch any deprecated code you're using. - LintMiddleware has moved to :mod:werkzeug.middleware.lint. - ProfilerMiddleware has moved to :mod:werkzeug.middleware.profiler. - ProxyFix has moved to :mod:werkzeug.middleware.proxy_fix. - JSONRequestMixin has moved to :mod:werkzeug.wrappers.json. - cache has been extracted into a separate project, cachelib <https://github.com/pallets/cachelib>_. The version in Werkzeug is deprecated. - securecookie and sessions have been extracted into a separate project, secure-cookie <https://github.com/pallets/secure-cookie>_. The version in Werkzeug is deprecated. - Everything in fixers, except ProxyFix, is deprecated. - Everything in wrappers, except JSONMixin, is deprecated. - atom is deprecated. This did not fit in with the rest of Werkzeug, and is better served by a dedicated library in the community. - jsrouting is removed. Set URLs when rendering templates or JSON responses instead. - limiter is removed. Its specific use is handled by Werkzeug directly, but stream limiting is better handled by the WSGI server in general. - testtools is removed. It did not offer significant benefit over the default test client. - iterio is deprecated. - :func:wsgi.get_host no longer looks at X-Forwarded-For. Use :class:~middleware.proxy_fix.ProxyFix to handle that. - :class:~middleware.proxy_fix.ProxyFix is refactored to support more headers, multiple values, and more secure configuration. - Each header supports multiple values. The trusted number of proxies is configured separately for each header. The num_proxies argument is deprecated. - Sets SERVER_NAME and SERVER_PORT based on X-Forwarded-Host. - Sets SERVER_PORT and modifies HTTP_HOST based on X-Forwarded-Port. - Sets SCRIPT_NAME based on X-Forwarded-Prefix. - The original WSGI environment values are stored in the werkzeug.proxy_fix.orig key, a dict. The individual keys werkzeug.proxy_fix.orig_remote_addr, werkzeug.proxy_fix.orig_wsgi_url_scheme, and werkzeug.proxy_fix.orig_http_host are deprecated. - Middleware from werkzeug.wsgi has moved to separate modules under werkzeug.middleware, along with the middleware moved from werkzeug.contrib. The old werkzeug.wsgi imports are deprecated and will be removed in version 1.0. - werkzeug.wsgi.DispatcherMiddleware has moved to :class:werkzeug.middleware.dispatcher.DispatcherMiddleware. - werkzeug.wsgi.ProxyMiddleware as moved to :class:werkzeug.middleware.http_proxy.ProxyMiddleware. - werkzeug.wsgi.SharedDataMiddleware has moved to :class:werkzeug.middleware.shared_data.SharedDataMiddleware. - :class:~middleware.http_proxy.ProxyMiddleware proxies the query string. - The filenames generated by :class:~middleware.profiler.ProfilerMiddleware can be customized. - The werkzeug.wrappers module has been converted to a package, and its various classes have been organized into separate modules. Any previously documented classes, understood to be the existing public API, are still importable from werkzeug.wrappers, or may be imported from their specific modules.
One would assume that this class implements the IOBase abstract. As the
underlying file-like object is either io.BytesIO, io.StringIO, or a true
file object, this is a reasonable abstract expect and to implement.
Regardless, the behaviour of this class does not change much in the case
of the attribute being missing from the underlying file-like; an
AttributeError is still raised, albeit from one additional frame on the
stack trace.
https://bugs.python.org/issue26175