build(deps): bump flask from 2.1.1 to 3.1.3 in /samples/server/petstore/python-flask

[dependabot]

Bumps flask from 2.1.1 to 3.1.3.

Release notes

Sourced from flask's releases.

3.1.3

This is the Flask 3.1.3 security fix release, which fixes a security issue but does not otherwise change behavior and should not result in breaking changes compared to the latest feature release.

PyPI: https://pypi.org/project/Flask/3.1.3/ Changes: https://flask.palletsprojects.com/page/changes/#version-3-1-3

• The session is marked as accessed for operations that only access the keys but not the values, such as in and len. GHSA-68rp-wp8r-4726

3.1.2

This is the Flask 3.1.2 fix release, which fixes bugs but does not otherwise change behavior and should not result in breaking changes compared to the latest feature release.

PyPI: https://pypi.org/project/Flask/3.1.2/ Changes: https://flask.palletsprojects.com/page/changes/#version-3-1-2 Milestone: https://github.com/pallets/flask/milestone/38?closed=1

• stream_with_context does not fail inside async views. #5774
• When using follow_redirects in the test client, the final state of session is correct. #5786
• Relax type hint for passing bytes IO to send_file. #5776

3.1.1

This is the Flask 3.1.1 fix release, which fixes bugs but does not otherwise change behavior and should not result in breaking changes compared to the latest feature release.

PyPI: https://pypi.org/project/Flask/3.1.1/ Changes: https://flask.palletsprojects.com/en/stable/changes/#version-3-1-1 Milestone https://github.com/pallets/flask/milestone/36?closed=1

• Fix signing key selection order when key rotation is enabled via SECRET_KEY_FALLBACKS. GHSA-4grg-w6v8-c28g
• Fix type hint for cli_runner.invoke. #5645
• flask --help loads the app and plugins first to make sure all commands are shown. #5673
• Mark sans-io base class as being able to handle views that return AsyncIterable. This is not accurate for Flask, but makes typing easier for Quart. #5659

3.1.0

This is the Flask 3.1.0 feature release. A feature release may include new features, remove previously deprecated code, add new deprecations, or introduce potentially breaking changes. We encourage everyone to upgrade, and to use a tool such as pip-tools to pin all dependencies and control upgrades. Test with warnings treated as errors to be able to adapt to deprecation warnings early.

PyPI: https://pypi.org/project/Flask/3.1.0/ Changes: https://flask.palletsprojects.com/en/stable/changes/#version-3-1-0 Milestone: https://github.com/pallets/flask/milestone/33?closed=1

• Drop support for Python 3.8. #5623
• Update minimum dependency versions to latest feature releases. Werkzeug >= 3.1, ItsDangerous >= 2.2, Blinker >= 1.9. #5624, #5633
• Provide a configuration option to control automatic option responses. #5496
• Flask.open_resource/open_instance_resource and Blueprint.open_resource take an encoding parameter to use when opening in text mode. It defaults to utf-8. #5504
• Request.max_content_length can be customized per-request instead of only through the MAX_CONTENT_LENGTH config. Added MAX_FORM_MEMORY_SIZE and MAX_FORM_PARTS config. Added documentation about resource limits to the security page. #5625
• Add support for the Partitioned cookie attribute (CHIPS), with the SESSION_COOKIE_PARTITIONED config. #5472
• -e path takes precedence over default .env and .flaskenv files. load_dotenv loads default files in addition to a path unless load_defaults=False is passed. #5628
• Support key rotation with the SECRET_KEY_FALLBACKS config, a list of old secret keys that can still be used for unsigning. Extensions will need to add support. #5621
• Fix how setting host_matching=True or subdomain_matching=False interacts with SERVER_NAME. Setting SERVER_NAME no longer restricts requests to only that domain. #5553
• Request.trusted_hosts is checked during routing, and can be set through the TRUSTED_HOSTS config. #5636

3.0.3

... (truncated)

Changelog

Sourced from flask's changelog.

Version 3.1.3

Released 2026-02-18

• The session is marked as accessed for operations that only access the keys but not the values, such as in and len. :ghsa:68rp-wp8r-4726

Version 3.1.2

Released 2025-08-19

• stream_with_context does not fail inside async views. :issue:5774
• When using follow_redirects in the test client, the final state of session is correct. :issue:5786
• Relax type hint for passing bytes IO to send_file. :issue:5776

Version 3.1.1

Released 2025-05-13

• Fix signing key selection order when key rotation is enabled via SECRET_KEY_FALLBACKS. :ghsa:4grg-w6v8-c28g
• Fix type hint for cli_runner.invoke. :issue:5645
• flask --help loads the app and plugins first to make sure all commands are shown. :issue:5673
• Mark sans-io base class as being able to handle views that return AsyncIterable. This is not accurate for Flask, but makes typing easier for Quart. :pr:5659

Version 3.1.0

Released 2024-11-13

• Drop support for Python 3.8. :pr:5623
• Update minimum dependency versions to latest feature releases. Werkzeug >= 3.1, ItsDangerous >= 2.2, Blinker >= 1.9. :pr:5624,5633
• Provide a configuration option to control automatic option responses. :pr:5496
• Flask.open_resource/open_instance_resource and Blueprint.open_resource take an encoding parameter to use when opening in text mode. It defaults to utf-8. :issue:5504
• Request.max_content_length can be customized per-request instead of only through the MAX_CONTENT_LENGTH config. Added

... (truncated)

Commits

• 22d9247 release version 3.1.3
• 089cb86 Merge commit from fork
• c17f379 request context tracks session access
• 27be933 start version 3.1.3
• 4e652d3 Abort if the instance folder cannot be created (#5903)
• 3d03098 Abort if the instance folder cannot be created
• 407eb76 document using gevent for async (#5900)
• ac5664d document using gevent for async
• 4f79d5b Increase required flit_core version to 3.11 (#5865)
• fe3b215 Increase required flit_core version to 3.11
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
  You can disable automated security fix PRs for this repo from the Security Alerts page.

---

Summary by cubic

Upgrade Flask from 2.1.1 to 3.1.3 in the Python Flask Petstore sample to apply the latest security fix and bug fixes.

• Dependencies
  • Flask 3.1.3 includes a security fix for session access (GHSA-68rp-wp8r-4726).
  • Requires Python 3.9+ and updated transitive deps (Werkzeug >= 3.1, ItsDangerous >= 2.2, Blinker >= 1.9).

^{Written for commit c42ca9e. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="samples/server/petstore/python-flask/requirements.txt">

<violation number="1" location="samples/server/petstore/python-flask/requirements.txt:13">
P2: Flask 3.1.x requires Python 3.9+, but this sample documents Python 3.5.2+ and already has 3.4/3.5-specific pins. Bumping to Flask 3.1.3 without a version marker will cause installs to fail on the older Python versions this sample advertises. Gate the Flask version by Python version and/or update the documented minimum Python version.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: Flask 3.1.x requires Python 3.9+, but this sample documents Python 3.5.2+ and already has 3.4/3.5-specific pins. Bumping to Flask 3.1.3 without a version marker will cause installs to fail on the older Python versions this sample advertises. Gate the Flask version by Python version and/or update the documented minimum Python version.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At samples/server/petstore/python-flask/requirements.txt, line 13:

<comment>Flask 3.1.x requires Python 3.9+, but this sample documents Python 3.5.2+ and already has 3.4/3.5-specific pins. Bumping to Flask 3.1.3 without a version marker will cause installs to fail on the older Python versions this sample advertises. Gate the Flask version by Python version and/or update the documented minimum Python version.</comment>

<file context>
@@ -10,4 +10,4 @@ werkzeug == 0.16.1; python_version=="3.5" or python_version=="3.4"
 python_dateutil >= 2.6.0
 setuptools >= 21.0.0
-Flask == 2.1.1
+Flask == 3.1.3
</file context>

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version. You can also ignore all major, minor, or patch releases for a dependency by adding an ignore condition with the desired update_types to your config file.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.