langgenius/dify

[Chore/Refactor] Remove `server_default` in model definitions

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#29314 opened on Dec 9, 2025

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 (4 comments) (1 reaction) (1 assignee)TypeScript (141,412 stars) (22,210 forks)batch import
good first issuerefactor

Description

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Description

Summary

PR #28188 introduced MySQL support and adjusted migration accordingly. However, the model definition is not adjusted, and most models still contains the server_default=sa.text('uuid_generate_v4()') option. While the server_default argument is only used to generate migration and not applied while running application, it still causes confusion, especially for new model definitions, as implementors of new models (both real humans and AIs) generally references existing model definitions as examples.

Solution

Remove the server_default parameter from UUID column definitions in model files, allowing the application layer to handle database-specific UUID generation by setting the default=uuid.uuid4 option for those models.

Motivation

No response

Additional Context

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Contributor guide

Tech stack
pythonsqlpostgresqlmysql
Domain
backenddatabase
Issue type
refactor
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
blocked
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
PythonSQLAlchemyDatabase schema basics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60
Research direction
Search for all model definition files in the repository that define UUID columns with server default=sa.text('uuid generate v4()'). Remove that parameter and ensure a default=uuid.uuid4 is set instead. Reference the existing model definitions and PR #28188 for context. Check comments in the issue for any additional guidance.