[PR #21398] [CLOSED] fix: JSONField double deserialization on PostgreSQL #64922

New Issue

GiteaMirror · 2026-05-06T10:39:42-05:00

GiteaMirror commented

2026-05-06 10:39:42 -05:00

📋 Pull Request Information

Original PR: https://github.com/open-webui/open-webui/pull/21398
Author: @lewisco
Created: 2/13/2026
Status: ❌ Closed

Base: dev ← Head: fix/jsonfield-double-deserialization

📝 Commits (1)

9a55aa6 fix: handle already-deserialized JSON values from PostgreSQL

📊 Changes

1 file changed (+5 additions, -2 deletions)

View changed files

📝 backend/open_webui/internal/db.py (+5 -2)

📄 Description

Description

Fix JSONField.process_result_value crashing with TypeError on PostgreSQL when psycopg2 returns already-deserialized Python dicts/lists from JSONB columns. The bug surfaces most visibly when creating a new skill, as db.refresh() triggers deserialization of the meta column.

Discussion: https://github.com/open-webui/open-webui/discussions/21397

Added

N/A

Changed

N/A

Deprecated

N/A

Removed

N/A

Fixed

JSONField.process_result_value now checks whether the value is already a dict or list before calling json.loads(). On PostgreSQL with psycopg2's native JSON type adaptation, JSONB columns return Python objects directly. The previous unconditional json.loads(value) raised TypeError: the JSON object must be str, bytes or bytearray, not dict.

Security

N/A

Breaking Changes

N/A

Additional Information

Single file change: backend/open_webui/internal/db.py, 3 lines added, 2 removed
SQLite is unaffected (always returns JSON as text strings), but the fix is safe for both backends
The Peewee equivalent python_value (same file, lines 51-53) has the same unconditional json.loads but is left out of scope to keep this minimal
Co-authored with AI, manually reviewed and tested on both PostgreSQL and SQLite

Testing

PostgreSQL (live deployment, psycopg2 driver):

Skill creation works (previously crashed on db.refresh())
All JSONB column reads return correctly

SQLite (local Docker, ghcr.io/open-webui/open-webui:main with patched file bind-mounted):

Test	JSONField columns hit	Result
Create skill (with tags in meta)	`skill.meta`	PASS
Read skill back	`skill.meta`	PASS
List skills (multiple reads)	`skill.meta`	PASS
Create chat	`chat.chat`	PASS
Read chat back	`chat.chat`	PASS
Update chat (nested dicts, lists, child objects)	`chat.chat`	PASS
Update user settings	`user.settings`	PASS
Read user settings back	`user.settings`	PASS
Empty lists, null values, empty dicts	`chat.chat`	PASS

On SQLite the isinstance guard never triggers because values always arrive as strings, so json.loads() runs exactly as before. Zero errors in container logs.

Screenshots or Videos

N/A (backend-only change, no UI impact)

Contributor License Agreement

By submitting this pull request, I confirm that I have read and fully agree to the Contributor License Agreement (CLA), and I am providing my contributions under its terms.

_{🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.}

## 📋 Pull Request Information **Original PR:** https://github.com/open-webui/open-webui/pull/21398 **Author:** [@lewisco](https://github.com/lewisco) **Created:** 2/13/2026 **Status:** ❌ Closed **Base:** `dev` ← **Head:** `fix/jsonfield-double-deserialization` --- ### 📝 Commits (1) - [`9a55aa6`](https://github.com/open-webui/open-webui/commit/9a55aa63e8c040c96f93a347baace8ea877d12f4) fix: handle already-deserialized JSON values from PostgreSQL ### 📊 Changes **1 file changed** (+5 additions, -2 deletions) <details> <summary>View changed files</summary> 📝 `backend/open_webui/internal/db.py` (+5 -2) </details> ### 📄 Description ### Description - Fix `JSONField.process_result_value` crashing with `TypeError` on PostgreSQL when psycopg2 returns already-deserialized Python dicts/lists from JSONB columns. The bug surfaces most visibly when creating a new skill, as `db.refresh()` triggers deserialization of the `meta` column. Discussion: https://github.com/open-webui/open-webui/discussions/21397 ### Added - N/A ### Changed - N/A ### Deprecated - N/A ### Removed - N/A ### Fixed - `JSONField.process_result_value` now checks whether the value is already a `dict` or `list` before calling `json.loads()`. On PostgreSQL with psycopg2's native JSON type adaptation, JSONB columns return Python objects directly. The previous unconditional `json.loads(value)` raised `TypeError: the JSON object must be str, bytes or bytearray, not dict`. ### Security - N/A ### Breaking Changes - N/A --- ### Additional Information - Single file change: `backend/open_webui/internal/db.py`, 3 lines added, 2 removed - SQLite is unaffected (always returns JSON as text strings), but the fix is safe for both backends - The Peewee equivalent `python_value` (same file, lines 51-53) has the same unconditional `json.loads` but is left out of scope to keep this minimal - Co-authored with AI, manually reviewed and tested on both PostgreSQL and SQLite ### Testing **PostgreSQL (live deployment, psycopg2 driver):** - Skill creation works (previously crashed on `db.refresh()`) - All JSONB column reads return correctly **SQLite (local Docker, `ghcr.io/open-webui/open-webui:main` with patched file bind-mounted):** | Test | JSONField columns hit | Result | |------|----------------------|--------| | Create skill (with tags in meta) | `skill.meta` | PASS | | Read skill back | `skill.meta` | PASS | | List skills (multiple reads) | `skill.meta` | PASS | | Create chat | `chat.chat` | PASS | | Read chat back | `chat.chat` | PASS | | Update chat (nested dicts, lists, child objects) | `chat.chat` | PASS | | Update user settings | `user.settings` | PASS | | Read user settings back | `user.settings` | PASS | | Empty lists, null values, empty dicts | `chat.chat` | PASS | On SQLite the `isinstance` guard never triggers because values always arrive as strings, so `json.loads()` runs exactly as before. Zero errors in container logs. ### Screenshots or Videos N/A (backend-only change, no UI impact) ### Contributor License Agreement By submitting this pull request, I confirm that I have read and fully agree to the [Contributor License Agreement (CLA)](https://github.com/open-webui/open-webui/blob/main/CONTRIBUTOR_LICENSE_AGREEMENT), and I am providing my contributions under its terms. --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>

GiteaMirror added the pull-request label 2026-05-06 10:39:42 -05:00

GiteaMirror closed this issue

2026-05-06 10:39:44 -05:00

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Reference: github-starred/open-webui#64922