feat: Support allOf in OpenAPI properties inside schema #22946

[mike1936]

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Summary

Currently the OpenAPI parser does not handles allOf keyword in the properties of a OpenAPI schema object, this PR tries to implement it.

Basically the key-value pairs of each obj defined inside allOf is merged into the original property, with some special considerations listed as follows:

• if the value to be merged is a list, those items are concatenated
• if the value type is not a list, it got merged only if the original property does not have that key

Fix: #22946

Screenshots

Not available since its a backend-specific change.

Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods

[crazywoola]

Please link an issue in the description.

[mike1936]

fix #22946

[Copilot]

Pull Request Overview

This PR adds support for the allOf keyword in OpenAPI schema properties to properly handle schema composition and inheritance. The implementation merges properties from allOf objects into the parent property definition.

• Implements allOf keyword handling for properties within OpenAPI schema objects
• Merges key-value pairs from each allOf object with special handling for lists (concatenation) vs other types (merge if key doesn't exist)
• Adds test coverage for the new functionality with both direct schemas and $ref references

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
api/core/tools/utils/parser.py	Implements allOf property merging logic with reference resolution and type-specific merge strategies
api/tests/unit_tests/core/tools/utils/test_parser.py	Adds comprehensive test case covering allOf with references and enum merging scenarios

[crazywoola]

Please see the comments if you have some time.