[GH-ISSUE #24564] bug: API calls to /api/chat/completions fail: "'NoneType' object has no attribute 'startswith'" #107330

New Issue

GiteaMirror · 2026-05-18T06:07:08-05:00

GiteaMirror commented

2026-05-18 06:07:08 -05:00

Originally created by @da-astro on GitHub (May 11, 2026).
Original GitHub issue: https://github.com/open-webui/open-webui/issues/24564

Check Existing Issues

I have searched for any existing and/or related issues.
I have searched for any existing and/or related discussions.
I have also searched in the CLOSED issues AND CLOSED discussions and found no related items (your issue might already be addressed on the development branch!).
I am using the latest version of Open WebUI.

Installation Method

Docker

Open WebUI Version

main branch, image pulled 2026-05-10 (commit 3660bc00fd)

Ollama Version (if applicable)

0.23.2

Operating System

Ubuntu 24.04 LTS (server)

Browser (if applicable)

N/A — this is an API-only bug, no browser involved.

Confirmation

I have read and followed all instructions in README.md.
I am using the latest version of both Open WebUI and Ollama.
I have included the browser console logs.
I have included the Docker container logs.
I have provided every relevant configuration, setting, and environment variable used in my setup.
I have clearly listed every relevant configuration, custom setting, environment variable, and command-line option that influences my setup (such as Docker Compose overrides, .env values, browser settings, authentication configurations, etc).
I have documented step-by-step reproduction instructions that are precise, sequential, and leave nothing to interpretation. My steps:
Start with the initial platform/version/OS and dependencies used,
Specify exact install/launch/configure commands,
List URLs visited, user input (incl. example values/emails/passwords if needed),
Describe all options and toggles enabled or changed,
Include any files or environmental changes,
Identify the expected and actual result at each stage,
Ensure any reasonably skilled user can follow and hit the same issue.

Expected Behavior

API requests to /api/chat/completions should return a successful chat completion response, as documented at https://docs.openwebui.com/reference/api-endpoints.

Actual Behavior

Every API request to /api/chat/completions returns HTTP 400 with:

{"detail":"'NoneType' object has no attribute 'startswith'"}

This affects all models (Ollama and OpenAI-compatible/Anthropic). The same models work correctly through the browser UI.

Steps to Reproduce

Start with Ubuntu 24.04 server running Docker.

Run Open WebUI via Docker:

docker run -d -p 3000:8080 --name open-webui \
  -v open-webui:/app/backend/data \
  ghcr.io/open-webui/open-webui:main

Connect Ollama (running on the host at port 11434) and/or an OpenAI-compatible API (e.g. Anthropic) via Admin Panel → Settings → Connections.
Verify models work in the browser UI — send a message to any model and confirm a response.
Enable API Keys in Admin Panel → Settings → General → Enable API Keys.
Obtain a JWT token from the browser console:
```
localStorage.getItem('token')
```

Send an API request:

curl -X POST http://localhost:3000/api/chat/completions \
  -H "Authorization: Bearer YOUR_JWT_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"model":"llama3.2:latest","messages":[{"role":"user","content":"hi"}]}'

Observe the response: {"detail":"'NoneType' object has no attribute 'startswith'"}

No environment variables, Docker Compose overrides, or custom settings were used beyond the steps above.

Logs & Screenshots

Docker container log at the moment of the failing request:

2026-05-11 04:32:59.469 | ERROR | open_webui.main:process_chat:2015 - Error processing chat payload: 'NoneType' object has no attribute 'startswith'
2026-05-11 04:32:59.469 | INFO  | uvicorn.protocols.http.httptools_impl:send:483 - 192.168.4.50:0 - "POST /api/chat/completions HTTP/1.1" 400

Full traceback (obtained by adding log.error('Full traceback: %s', traceback.format_exc()) to the error handler in main.py):

Traceback (most recent call last):
  File "/app/backend/open_webui/main.py", line 1977, in process_chat
    form_data, metadata, events = await process_chat_payload(request, form_data, user, metadata, model)
  File "/app/backend/open_webui/utils/middleware.py", line 2359, in process_chat_payload
    event_emitter = await get_event_emitter(metadata)
  File "/app/backend/open_webui/socket/main.py", line 902, in get_event_emitter
    if request_info.get('chat_id', '').startswith('channel:'):
AttributeError: 'NoneType' object has no attribute 'startswith'

Additional Information

Root cause

In open_webui/socket/main.py, line 902:

if request_info.get('chat_id', '').startswith('channel:'):

When called via the API (no browser chat session), metadata['chat_id'] is None. The .get('chat_id', '') call returns None rather than the default '' because the key exists in the dict with a None value — dict.get() only uses the default when the key is absent, not when its value is None.

Fix

Replace:

request_info.get('chat_id', '').startswith(...)

with:

(request_info.get('chat_id') or '').startswith(...)

The same pattern exists in multiple other places across the codebase and should be fixed everywhere:

open_webui/socket/main.py line 902 — primary crash site
open_webui/utils/middleware.py — ~11 instances of metadata['chat_id'].startswith(...) without a null guard
open_webui/main.py — 1 instance of metadata['chat_id'].startswith(...)

This bug makes the documented OpenAI-compatible API endpoint (/api/chat/completions) completely non-functional for any external client. The browser UI is unaffected because it always provides a chat_id via the WebSocket session.

Originally created by @da-astro on GitHub (May 11, 2026). Original GitHub issue: https://github.com/open-webui/open-webui/issues/24564 ### Check Existing Issues - [x] I have searched for any existing and/or related issues. - [x] I have searched for any existing and/or related discussions. - [x] I have also searched in the CLOSED issues AND CLOSED discussions and found no related items (your issue might already be addressed on the development branch!). - [x] I am using the latest version of Open WebUI. ### Installation Method Docker ### Open WebUI Version main branch, image pulled 2026-05-10 (commit 3660bc00fd807deced3400a63bfa6db47811a3bb) ### Ollama Version (if applicable) 0.23.2 ### Operating System Ubuntu 24.04 LTS (server) ### Browser (if applicable) N/A — this is an API-only bug, no browser involved. ### Confirmation - [x] I have read and followed all instructions in `README.md`. - [x] I am using the latest version of **both** Open WebUI and Ollama. - [x] I have included the browser console logs. - [x] I have included the Docker container logs. - [x] I have **provided every relevant configuration, setting, and environment variable used in my setup.** - [x] I have clearly **listed every relevant configuration, custom setting, environment variable, and command-line option that influences my setup** (such as Docker Compose overrides, .env values, browser settings, authentication configurations, etc). - [x] I have documented **step-by-step reproduction instructions that are precise, sequential, and leave nothing to interpretation**. My steps: - Start with the initial platform/version/OS and dependencies used, - Specify exact install/launch/configure commands, - List URLs visited, user input (incl. example values/emails/passwords if needed), - Describe all options and toggles enabled or changed, - Include any files or environmental changes, - Identify the expected and actual result at each stage, - Ensure any reasonably skilled user can follow and hit the same issue. ### Expected Behavior API requests to `/api/chat/completions` should return a successful chat completion response, as documented at https://docs.openwebui.com/reference/api-endpoints. ### Actual Behavior Every API request to `/api/chat/completions` returns HTTP 400 with: ```json {"detail":"'NoneType' object has no attribute 'startswith'"} ``` This affects all models (Ollama and OpenAI-compatible/Anthropic). The same models work correctly through the browser UI. ### Steps to Reproduce 1. Start with Ubuntu 24.04 server running Docker. 2. Run Open WebUI via Docker: ```bash docker run -d -p 3000:8080 --name open-webui \ -v open-webui:/app/backend/data \ ghcr.io/open-webui/open-webui:main ``` 3. Connect Ollama (running on the host at port 11434) and/or an OpenAI-compatible API (e.g. Anthropic) via Admin Panel → Settings → Connections. 4. Verify models work in the browser UI — send a message to any model and confirm a response. 5. Enable API Keys in Admin Panel → Settings → General → Enable API Keys. 6. Obtain a JWT token from the browser console: ```javascript localStorage.getItem('token') ``` 7. Send an API request: ```bash curl -X POST http://localhost:3000/api/chat/completions \ -H "Authorization: Bearer YOUR_JWT_TOKEN" \ -H "Content-Type: application/json" \ -d '{"model":"llama3.2:latest","messages":[{"role":"user","content":"hi"}]}' ``` 8. Observe the response: `{"detail":"'NoneType' object has no attribute 'startswith'"}` No environment variables, Docker Compose overrides, or custom settings were used beyond the steps above. ### Logs & Screenshots Docker container log at the moment of the failing request: ``` 2026-05-11 04:32:59.469 | ERROR | open_webui.main:process_chat:2015 - Error processing chat payload: 'NoneType' object has no attribute 'startswith' 2026-05-11 04:32:59.469 | INFO | uvicorn.protocols.http.httptools_impl:send:483 - 192.168.4.50:0 - "POST /api/chat/completions HTTP/1.1" 400 ``` Full traceback (obtained by adding `log.error('Full traceback: %s', traceback.format_exc())` to the error handler in `main.py`): ``` Traceback (most recent call last): File "/app/backend/open_webui/main.py", line 1977, in process_chat form_data, metadata, events = await process_chat_payload(request, form_data, user, metadata, model) File "/app/backend/open_webui/utils/middleware.py", line 2359, in process_chat_payload event_emitter = await get_event_emitter(metadata) File "/app/backend/open_webui/socket/main.py", line 902, in get_event_emitter if request_info.get('chat_id', '').startswith('channel:'): AttributeError: 'NoneType' object has no attribute 'startswith' ``` ### Additional Information ## Root cause In `open_webui/socket/main.py`, line 902: ```python if request_info.get('chat_id', '').startswith('channel:'): ``` When called via the API (no browser chat session), `metadata['chat_id']` is `None`. The `.get('chat_id', '')` call returns `None` rather than the default `''` because the key **exists** in the dict with a `None` value — `dict.get()` only uses the default when the key is **absent**, not when its value is `None`. ## Fix Replace: ```python request_info.get('chat_id', '').startswith(...) ``` with: ```python (request_info.get('chat_id') or '').startswith(...) ``` The same pattern exists in multiple other places across the codebase and should be fixed everywhere: - `open_webui/socket/main.py` line 902 — **primary crash site** - `open_webui/utils/middleware.py` — ~11 instances of `metadata['chat_id'].startswith(...)` without a null guard - `open_webui/main.py` — 1 instance of `metadata['chat_id'].startswith(...)` This bug makes the documented OpenAI-compatible API endpoint (`/api/chat/completions`) completely non-functional for any external client. The browser UI is unaffected because it always provides a `chat_id` via the WebSocket session.

GiteaMirror added the bug label 2026-05-18 06:07:08 -05:00

GiteaMirror closed this issue

2026-05-18 06:07:18 -05:00

GiteaMirror commented

2026-05-18 06:07:19 -05:00

@owui-terminator[bot] commented on GitHub (May 11, 2026):

⚠️ Missing Issue Title Prefix

@da-astro, your issue title is missing a categorising prefix (e.g. bug:, feat:, docs:).

Please update the title to lead with one of:

bug: bug report or error
feat: feature request or enhancement
docs: documentation issue
question: usage question
help: support request

Example: bug: Login fails when the password contains special characters

@owui-terminator[bot] commented on GitHub (May 11, 2026): # ⚠️ Missing Issue Title Prefix @da-astro, your issue title is missing a categorising prefix (e.g. `bug:`, `feat:`, `docs:`). Please update the title to lead with one of: - **bug**: bug report or error - **feat**: feature request or enhancement - **docs**: documentation issue - **question**: usage question - **help**: support request Example: `bug: Login fails when the password contains special characters`

GiteaMirror commented

2026-05-18 06:07:19 -05:00

@owui-terminator[bot] commented on GitHub (May 11, 2026):

🔍 Related Issues Found

I found some existing issues that might be related. Please check if any of these are duplicates or contain helpful solutions:

🟣 #24550 bug: NoneType object has no attribute 'startswith' — all /api/v1/chat/completions calls return 400 (v0.9.5, direct connections)
This is the closest match: it reports the same 'NoneType' object has no attribute 'startswith' error on completions API calls, affecting external/API clients while the web UI works. The reported endpoint differs only by /api/v1/chat/completions vs /api/chat/completions, but the failure mode and root symptom are the same.
by ThefloorMiner
🟢 #24553 issue: /api/chat/completions runs into error
This open issue describes the same completions API crash with the exact 'NoneType' object has no attribute 'startswith' message on v0.9.5. Its reproduction is an API-only POST to /api/chat/completions, making it highly overlapping with the new report.
by tweinberger-lei · bug
🟣 #24554 issue: Open WebUI v0.9.5 Broken Completions API
This closed issue is another report of the completions API becoming broken in v0.9.5 with the same 400/error text and multiple external clients affected. It appears to be the same regression from a different reporter and client setup.
by xcjs · bug

💡 If your issue is a duplicate, please close it and add any additional details to the existing issue instead.

This comment was generated automatically. React with 👍 if helpful, 👎 if not.

@owui-terminator[bot] commented on GitHub (May 11, 2026):  🔍 **Related Issues Found** I found some existing issues that might be related. Please check if any of these are duplicates or contain helpful solutions: 1. 🟣 [#24550](https://github.com/open-webui/open-webui/issues/24550) **bug: NoneType object has no attribute 'startswith' — all /api/v1/chat/completions calls return 400 (v0.9.5, direct connections)** *This is the closest match: it reports the same `'NoneType' object has no attribute 'startswith'` error on completions API calls, affecting external/API clients while the web UI works. The reported endpoint differs only by `/api/v1/chat/completions` vs `/api/chat/completions`, but the failure mode and root symptom are the same.* *by ThefloorMiner* 2. 🟢 [#24553](https://github.com/open-webui/open-webui/issues/24553) **issue: /api/chat/completions runs into error** *This open issue describes the same completions API crash with the exact `'NoneType' object has no attribute 'startswith'` message on v0.9.5. Its reproduction is an API-only POST to `/api/chat/completions`, making it highly overlapping with the new report.* *by tweinberger-lei · `bug`* 3. 🟣 [#24554](https://github.com/open-webui/open-webui/issues/24554) **issue: Open WebUI v0.9.5 Broken Completions API** *This closed issue is another report of the completions API becoming broken in v0.9.5 with the same 400/error text and multiple external clients affected. It appears to be the same regression from a different reporter and client setup.* *by xcjs · `bug`* --- 💡 If your issue is a duplicate, please close it and add any additional details to the existing issue instead. *This comment was generated automatically.* React with 👍 if helpful, 👎 if not.

GiteaMirror commented

2026-05-18 06:07:20 -05:00

@sacredbone commented on GitHub (May 11, 2026):

I receive the same error message when the LLM is using generate_image with a connected local comfyUI installation:

{
    "type": "function_call",
    "id": "call_o6kbvrt0",
    "call_id": "call_o6kbvrt0",
    "name": "generate_image",
    "arguments": "{\"prompt\": \"A cute, small, highly detailed robot, standing in a vibrant, sunlit meadow. The robot has big, expressive blue optical sensors and small, articulated limbs. Cinematic lighting with gentle sun rays filtering through the green leaves. The robot should have a slightly weathered, polished metallic chassis. Cute, Pixar/anime style, 8k resolution.\"}",
    "status": "completed"
  },
  {
    "type": "function_call_output",
    "id": "fco_89f9348aba1c4133838042a6",
    "call_id": "call_o6kbvrt0",
    "output": [
      {
        "type": "input_text",
        "text": "{\n  \"success\": false,\n  \"error\": \"Internal error: 400: [ERROR: 'NoneType' object has no attribute 'lower']\",\n  \"internal_trace\": \"Traceback (most recent call last):\\n  File \\\"/app/backend/open_webui/routers/images.py\\\", line 714, in image_generations\\n    _, url = await upload_image(\\n             ^^^^^^^^^^^^^^^^^^^\\n  File \\\"/app/backend/open_webui/routers/images.py\\\", line 475, in upload_image\\n    image_format = mimetypes.guess_extension(content_type)\\n                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n  File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 347, in guess_extension\\n    return _db.guess_extension(type, strict)\\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n  File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 202, in guess_extension\\n    extensions = self.guess_all_extensions(type, strict)\\n                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n  File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 181, in guess_all_extensions\\n    type = type.lower()\\n           ^^^^^^^^^^\\nAttributeError: 'NoneType' object has no attribute 'lower'\\n\\nDuring handling of the above exception, another exception occurred:\\n\\nTraceback (most recent call last):\\n  File \\\"<string>\\\", line 448, in generate_image\\n  File \\\"/app/backend/open_webui/routers/images.py\\\", line 773, in image_generations\\n    raise HTTPException(status_code=400, detail=ERROR_MESSAGES.DEFAULT(error))\\nfastapi.exceptions.HTTPException: 400: [ERROR: 'NoneType' object has no attribute 'lower']\\n\",\n  \"valves_config\": {\n    \"debug\": true,\n    \"verbose\": true\n  }\n}"
      }
    ],
    "status": "completed"
  },

The image is generated on to comfyui side and not received/stored in openwebui.

@sacredbone commented on GitHub (May 11, 2026): I receive the same error message when the LLM is using generate_image with a connected local comfyUI installation: ``` { "type": "function_call", "id": "call_o6kbvrt0", "call_id": "call_o6kbvrt0", "name": "generate_image", "arguments": "{\"prompt\": \"A cute, small, highly detailed robot, standing in a vibrant, sunlit meadow. The robot has big, expressive blue optical sensors and small, articulated limbs. Cinematic lighting with gentle sun rays filtering through the green leaves. The robot should have a slightly weathered, polished metallic chassis. Cute, Pixar/anime style, 8k resolution.\"}", "status": "completed" }, { "type": "function_call_output", "id": "fco_89f9348aba1c4133838042a6", "call_id": "call_o6kbvrt0", "output": [ { "type": "input_text", "text": "{\n \"success\": false,\n \"error\": \"Internal error: 400: [ERROR: 'NoneType' object has no attribute 'lower']\",\n \"internal_trace\": \"Traceback (most recent call last):\\n File \\\"/app/backend/open_webui/routers/images.py\\\", line 714, in image_generations\\n _, url = await upload_image(\\n ^^^^^^^^^^^^^^^^^^^\\n File \\\"/app/backend/open_webui/routers/images.py\\\", line 475, in upload_image\\n image_format = mimetypes.guess_extension(content_type)\\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 347, in guess_extension\\n return _db.guess_extension(type, strict)\\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 202, in guess_extension\\n extensions = self.guess_all_extensions(type, strict)\\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\\n File \\\"/usr/local/lib/python3.11/mimetypes.py\\\", line 181, in guess_all_extensions\\n type = type.lower()\\n ^^^^^^^^^^\\nAttributeError: 'NoneType' object has no attribute 'lower'\\n\\nDuring handling of the above exception, another exception occurred:\\n\\nTraceback (most recent call last):\\n File \\\"<string>\\\", line 448, in generate_image\\n File \\\"/app/backend/open_webui/routers/images.py\\\", line 773, in image_generations\\n raise HTTPException(status_code=400, detail=ERROR_MESSAGES.DEFAULT(error))\\nfastapi.exceptions.HTTPException: 400: [ERROR: 'NoneType' object has no attribute 'lower']\\n\",\n \"valves_config\": {\n \"debug\": true,\n \"verbose\": true\n }\n}" } ], "status": "completed" }, ``` The image is generated on to comfyui side and not received/stored in openwebui.

GiteaMirror commented

2026-05-18 06:07:20 -05:00

@da-astro commented on GitHub (May 11, 2026):

Duplicate of #24553

@da-astro commented on GitHub (May 11, 2026): Duplicate of #24553

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Reference: github-starred/open-webui#107330