langgenius/dify
1
0
Fork 0
mirror of https://github.com/langgenius/dify.git synced 2026-08-24 22:11:36 -04:00
Code Issues 775 Packages Projects Releases 10 Wiki Activity

[PR #31221] fix: add unique constraint to tenant_default_models to prevent duplic… #33141

New Issue
Closed
opened 2026-02-21 20:52:44 -05:00 by yindo · 0 comments
yindo commented 2026-02-21 20:52:44 -05:00
Owner
Copy Link
Copy Source

Original Pull Request: https://github.com/langgenius/dify/pull/31221

State: closed
Merged: Yes

Important

  1. Make sure you have read our contribution guidelines
  2. Ensure there is an associated issue and you have been assigned to it
  3. Use the correct syntax to link this PR: Fixes #<issue number>.

Summary

Fixes https://github.com/langgenius/dify/issues/31220

Problem

The tenant_default_models table is missing a unique constraint on (tenant_id, model_type), which causes system model settings to appear lost after page refresh.

Root cause:

  1. Race condition on concurrent saves: The code uses a "check-then-insert" pattern without proper locking in provider_manager.py:

    default_model = db.session.scalar(stmt)  # Check
if default_model:
    # Update existing
else:
    # Create new  <-- Race condition here!

  2. Duplicate records: When multiple requests happen concurrently, duplicate records with the same tenant_id and model_type are inserted.

  3. Non-deterministic query results: When duplicates exist, db.session.scalar() returns an arbitrary record, causing inconsistent display.

Solution

  1. Add UniqueConstraint("tenant_id", "model_type") to TenantDefaultModel model definition in api/models/provider.py

  2. Create a database migration that:

    • Cleans up existing duplicate records (keeps the most recent one per tenant_id + model_type)
    • Adds the unique constraint

Changes

File Change
api/models/provider.py Add unique constraint to TenantDefaultModel model
api/migrations/versions/2026_01_19_1507-fix_tenant_default_model_unique.py New migration file

Screenshots

Before After
System model settings lost after page refresh due to duplicate records Settings persist correctly with unique constraint enforced

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 make lint and make type-check (backend) and cd web && npx lint-staged (frontend) to appease the lint gods
**Original Pull Request:** https://github.com/langgenius/dify/pull/31221 **State:** closed **Merged:** Yes --- > [!IMPORTANT] > > 1. Make sure you have read our [contribution guidelines](https://github.com/langgenius/dify/blob/main/CONTRIBUTING.md) > 1. Ensure there is an associated issue and you have been assigned to it > 1. Use the correct syntax to link this PR: `Fixes #<issue number>`. ## Summary Fixes https://github.com/langgenius/dify/issues/31220 ### Problem The `tenant_default_models` table is missing a unique constraint on `(tenant_id, model_type)`, which causes system model settings to appear lost after page refresh. **Root cause:** 1. **Race condition on concurrent saves**: The code uses a "check-then-insert" pattern without proper locking in `provider_manager.py`: ```python default_model = db.session.scalar(stmt) # Check if default_model: # Update existing else: # Create new <-- Race condition here! ``` 2. **Duplicate records**: When multiple requests happen concurrently, duplicate records with the same `tenant_id` and `model_type` are inserted. 3. **Non-deterministic query results**: When duplicates exist, `db.session.scalar()` returns an arbitrary record, causing inconsistent display. ### Solution 1. Add `UniqueConstraint("tenant_id", "model_type")` to `TenantDefaultModel` model definition in `api/models/provider.py` 2. Create a database migration that: - Cleans up existing duplicate records (keeps the most recent one per `tenant_id + model_type`) - Adds the unique constraint ### Changes | File | Change | |------|--------| | `api/models/provider.py` | Add unique constraint to `TenantDefaultModel` model | | `api/migrations/versions/2026_01_19_1507-fix_tenant_default_model_unique.py` | New migration file | ## Screenshots | Before | After | |--------|-------| | System model settings lost after page refresh due to duplicate records | Settings persist correctly with unique constraint enforced | ## Checklist - [ ] This change requires a documentation update, included: [Dify Document](https://github.com/langgenius/dify-docs) - [x] I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!) - [x] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change. - [x] I've updated the documentation accordingly. - [x] I ran `make lint` and `make type-check` (backend) and `cd web && npx lint-staged` (frontend) to appease the lint gods
yindo added the pull-request label 2026-02-21 20:52:44 -05:00
yindo closed this issue 2026-02-21 20:52:44 -05:00
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
Knowledge Pipeline
Proposal
WIP
cloud
dependencies
feat:webapp
good first issue
outdated
performance
pull-request
Mirrored from GitHub Pull Request
 python:uv
refactor
size:L
stale
status: accepting prs
status: blocked
status: in discussion
stt & tts
vulnerablity
web
wont-fix
🌊 feat:workflow
🌚 invalid
🐞 bug
👻 feat:rag
💪 enhancement
📚 documentation
🔨 feat:tools
🙋‍♂️ question
🙏 help wanted
🤔 cant-reproduce
🤖 feat:agent
No Label pull-request
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
yindo
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: langgenius/dify#33141
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?