fix: Tag filtering in /tools endpoint after schema migration to dict format by rakdutta · Pull Request #2588 · IBM/mcp-context-forge

rakdutta · 2026-01-30T12:38:58Z

Fixes tag-based filtering in the /tools endpoint after the migration from List[str] to List[Dict[str, str]].
Introduces a unified tag-filtering helper to correctly handle both legacy string tags and {id, label} tags across SQLite and PostgreSQL.
Resolves failures in both database-backed and in-memory filtering paths.
Adds unit tests to validate tag filtering behavior.
The same tag-filtering functionality is verified for resources, prompts, A2A server, server export, and tag servers.

Note: Testing should be performed using PostgreSQL.

Example for Verify tag-based filtering --

# Expected: returns tool which have local tags
  'http://localhost:4444/tools?include_pagination=false&include_inactive=false&tags=local' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json'\
 -H "Authorization: Bearer $MCPGATEWAY_BEARER_TOKEN"

Fixes #2329 Updates tag filtering in TagService.get_entities_by_tag() to use the cross-database compatible json_contains_tag_expr helper instead of the raw json_extract LIKE query that only worked with string arrays. Changes: - Replace func.json_extract(tags, "$").LIKE query with json_contains_tag_expr which supports both legacy string tags and new dict-format tags - Update PostgreSQL implementation to use table_valued() pattern for idiomatic SQLAlchemy handling of jsonb_array_elements (elem.c.value) - Update unit tests to mock database dialect for json_contains_tag_expr - Improve test mocking to use patch.object context manager - Fix docstring to reflect new implementation (was "JSON LIKE queries") - Add comprehensive tests for dict-format tags [{id, label}] - Add rigorous PostgreSQL SQL compilation tests with regex validation - Document design decision: DB filters by 'id' only (TagValidator ensures id is always present; label is for display only) The json_contains_tag_expr helper handles both formats: - Legacy: ["tag1", "tag2"] - Dict format: [{"id": "tag1", "label": "Tag 1"}, ...] PostgreSQL implementation uses table_valued() for explicit column reference: - func.jsonb_array_elements(...).table_valued("value").alias("elem") - elem.c.value.op("->>")("id") for proper column access Signed-off-by: Mihai Criveti <crivetimihai@gmail.com>

crivetimihai · 2026-01-31T16:50:31Z

Review Changes Applied

Rebased on main and squashed 7 commits into 1 clean commit. Made the following improvements based on code review:

PostgreSQL Implementation Fix

Changed from literal_column("elem") aliasing to idiomatic SQLAlchemy table_valued() pattern
Now uses func.jsonb_array_elements(...).table_valued("value").alias("elem") with elem.c.value.op("->>")("id")
This produces explicit elem.value ->> 'id' SQL instead of implicit elem ->> 'id'

Documentation & Tests

Fixed docstring in TagService.get_entities_by_tag() (was "JSON LIKE queries", now "json_contains_tag_expr")
Added design comments explaining id-only filtering (label is for display, TagValidator ensures id is always present)
Added 8 new tests for dict-format tags [{id, label}]
Added PostgreSQL SQL compilation tests with regex validation for elem.value pattern
Fixed pre-existing lint issues in test file

Verification

All 1886 service tests pass
Tested PostgreSQL SQL against real database - works correctly
Both string tags ["tag"] and dict tags [{"id": "tag", "label": "Tag"}] filter correctly

…2588) Fixes IBM#2329 Updates tag filtering in TagService.get_entities_by_tag() to use the cross-database compatible json_contains_tag_expr helper instead of the raw json_extract LIKE query that only worked with string arrays. Changes: - Replace func.json_extract(tags, "$").LIKE query with json_contains_tag_expr which supports both legacy string tags and new dict-format tags - Update PostgreSQL implementation to use table_valued() pattern for idiomatic SQLAlchemy handling of jsonb_array_elements (elem.c.value) - Update unit tests to mock database dialect for json_contains_tag_expr - Improve test mocking to use patch.object context manager - Fix docstring to reflect new implementation (was "JSON LIKE queries") - Add comprehensive tests for dict-format tags [{id, label}] - Add rigorous PostgreSQL SQL compilation tests with regex validation - Document design decision: DB filters by 'id' only (TagValidator ensures id is always present; label is for display only) The json_contains_tag_expr helper handles both formats: - Legacy: ["tag1", "tag2"] - Dict format: [{"id": "tag1", "label": "Tag 1"}, ...] PostgreSQL implementation uses table_valued() for explicit column reference: - func.jsonb_array_elements(...).table_valued("value").alias("elem") - elem.c.value.op("->>")("id") for proper column access Signed-off-by: Mihai Criveti <crivetimihai@gmail.com> Co-authored-by: Mihai Criveti <crivetimihai@gmail.com> Signed-off-by: hughhennnelly <hughhennelly06@gmail.com>

…2588) Fixes IBM#2329 Updates tag filtering in TagService.get_entities_by_tag() to use the cross-database compatible json_contains_tag_expr helper instead of the raw json_extract LIKE query that only worked with string arrays. Changes: - Replace func.json_extract(tags, "$").LIKE query with json_contains_tag_expr which supports both legacy string tags and new dict-format tags - Update PostgreSQL implementation to use table_valued() pattern for idiomatic SQLAlchemy handling of jsonb_array_elements (elem.c.value) - Update unit tests to mock database dialect for json_contains_tag_expr - Improve test mocking to use patch.object context manager - Fix docstring to reflect new implementation (was "JSON LIKE queries") - Add comprehensive tests for dict-format tags [{id, label}] - Add rigorous PostgreSQL SQL compilation tests with regex validation - Document design decision: DB filters by 'id' only (TagValidator ensures id is always present; label is for display only) The json_contains_tag_expr helper handles both formats: - Legacy: ["tag1", "tag2"] - Dict format: [{"id": "tag1", "label": "Tag 1"}, ...] PostgreSQL implementation uses table_valued() for explicit column reference: - func.jsonb_array_elements(...).table_valued("value").alias("elem") - elem.c.value.op("->>")("id") for proper column access Signed-off-by: Mihai Criveti <crivetimihai@gmail.com> Co-authored-by: Mihai Criveti <crivetimihai@gmail.com>

rakdutta marked this pull request as ready for review January 30, 2026 14:26

rakdutta requested review from crivetimihai, kevalmahajan and madhav165 as code owners January 30, 2026 14:26

crivetimihai self-assigned this Jan 31, 2026

crivetimihai force-pushed the fix_issue_2329_tag branch from 258b0d7 to 04b0c91 Compare January 31, 2026 16:50

crivetimihai approved these changes Jan 31, 2026

View reviewed changes

crivetimihai merged commit 49304f3 into main Jan 31, 2026
51 checks passed

crivetimihai deleted the fix_issue_2329_tag branch January 31, 2026 17:02

crivetimihai mentioned this pull request Jan 31, 2026

[BUG][TAGS]: get_entities_by_tag fails on PostgreSQL - uses SQLite json_extract function #2607

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fix: Tag filtering in /tools endpoint after schema migration to dict format#2588

fix: Tag filtering in /tools endpoint after schema migration to dict format#2588
crivetimihai merged 1 commit intomainfrom
fix_issue_2329_tag

rakdutta commented Jan 30, 2026

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crivetimihai commented Jan 31, 2026

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rakdutta commented Jan 30, 2026

Example for Verify tag-based filtering --

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crivetimihai commented Jan 31, 2026

Review Changes Applied

PostgreSQL Implementation Fix

Documentation & Tests

Verification

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