[PR #15892] [CLOSED] chore: fix development setup shows "unsupported method (frontend only)" error due to CORS misconfiguration #62831

New Issue

GiteaMirror · 2026-05-06T07:14:54-05:00

GiteaMirror commented

2026-05-06 07:14:54 -05:00

📋 Pull Request Information

Original PR: https://github.com/open-webui/open-webui/pull/15892
Author: @zetavg
Created: 7/20/2025
Status: ❌ Closed

Base: dev ← Head: fix-dev-cors

📝 Commits (1)

a95ca07 fix: Remove trailing slash from CORS_ALLOW_ORIGIN in dev.sh

📊 Changes

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

View changed files

📝 backend/dev.sh (+1 -1)

📄 Description

Problem

When running backend/dev.sh + npm run dev, developers encounter:

Frontend displays: "Oops! You're using an unsupported method (frontend
only). Please serve the WebUI from the backend."
Browser console shows CORS error for http://localhost:8080/api/config

Root Cause

The CORS_ALLOW_ORIGIN in backend/dev.sh seems to have a trailing slash that doesn't match browser requests:

Configured: http://localhost:5173/ (with slash)
Browser sends: http://localhost:5173 (no slash)

This mismatch causes CORS rejection, preventing the frontend from fetching APIs.

Solution

Remove the trailing slash from CORS_ALLOW_ORIGIN to match browser behavior.

I'm not entirely sure I understand everything correctly though. Maybe I've done something wrong that has led to this issue.

Pull Request Checklist

Note to first-time contributors: Please open a discussion post in Discussions and describe your changes before submitting a pull request.

Before submitting, make sure you've checked the following:

Target branch: Please verify that the pull request targets the dev branch.
Description: Provide a concise description of the changes made in this pull request.
(skipped for minor dev-only change) Changelog: Ensure a changelog entry following the format of Keep a Changelog is added at the bottom of the PR description.
Documentation: Have you updated relevant documentation Open WebUI Docs, or other documentation sources?
Dependencies: Are there any new dependencies? Have you updated the dependency versions in the documentation?
(tested locally) Testing: Have you written and run sufficient tests to validate the changes?
Code review: Have you performed a self-review of your code, addressing any coding standard issues and ensuring adherence to the project's coding standards?
Prefix: To clearly categorize this pull request, prefix the pull request title using one of the following:
- BREAKING CHANGE: Significant changes that may affect compatibility
- build: Changes that affect the build system or external dependencies
- ci: Changes to our continuous integration processes or workflows
- chore: Refactor, cleanup, or other non-functional code changes
- docs: Documentation update or addition
- feat: Introduces a new feature or enhancement to the codebase
- fix: Bug fix or error correction
- i18n: Internationalization or localization changes
- perf: Performance improvement
- refactor: Code restructuring for better maintainability, readability, or scalability
- style: Changes that do not affect the meaning of the code (white space, formatting, missing semi-colons, etc.)
- test: Adding missing tests or correcting existing tests
- WIP: Work in progress, a temporary label for incomplete or ongoing work

Changelog Entry

Description

[Concisely describe the changes made in this pull request, including any relevant motivation and impact (e.g., fixing a bug, adding a feature, or improving performance)]

Added

[List any new features, functionalities, or additions]

Changed

[List any changes, updates, refactorings, or optimizations]

Deprecated

[List any deprecated functionality or features that have been removed]

Removed

[List any removed features, files, or functionalities]

Fixed

[List any fixes, corrections, or bug fixes]

Security

[List any new or updated security-related changes, including vulnerability fixes]

Breaking Changes

BREAKING CHANGE: [List any breaking changes affecting compatibility or functionality]

Additional Information

[Insert any additional context, notes, or explanations for the changes]
- [Reference any related issues, commits, or other relevant information]

Screenshots or Videos

[Attach any relevant screenshots or videos demonstrating the changes]

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/15892 **Author:** [@zetavg](https://github.com/zetavg) **Created:** 7/20/2025 **Status:** ❌ Closed **Base:** `dev` ← **Head:** `fix-dev-cors` --- ### 📝 Commits (1) - [`a95ca07`](https://github.com/open-webui/open-webui/commit/a95ca0734f9b2fd66796ca4a334fc97944675c32) fix: Remove trailing slash from CORS_ALLOW_ORIGIN in dev.sh ### 📊 Changes **1 file changed** (+1 additions, -1 deletions) <details> <summary>View changed files</summary> 📝 `backend/dev.sh` (+1 -1) </details> ### 📄 Description ## Problem When running `backend/dev.sh` + `npm run dev`, developers encounter: - Frontend displays: "Oops! You're using an unsupported method (frontend only). Please serve the WebUI from the backend." - Browser console shows CORS error for `http://localhost:8080/api/config` ## Root Cause The `CORS_ALLOW_ORIGIN` in `backend/dev.sh` seems to have a trailing slash that doesn't match browser requests: - Configured: `http://localhost:5173/` (with slash) - Browser sends: `http://localhost:5173` (no slash) This mismatch causes CORS rejection, preventing the frontend from fetching APIs. ## Solution Remove the trailing slash from `CORS_ALLOW_ORIGIN` to match browser behavior. I'm not entirely sure I understand everything correctly though. Maybe I've done something wrong that has led to this issue. # Pull Request Checklist ### Note to first-time contributors: Please open a discussion post in [Discussions](https://github.com/open-webui/open-webui/discussions) and describe your changes before submitting a pull request. **Before submitting, make sure you've checked the following:** - [x] **Target branch:** Please verify that the pull request targets the `dev` branch. - [x] **Description:** Provide a concise description of the changes made in this pull request. - [ ] (skipped for minor dev-only change) **Changelog:** Ensure a changelog entry following the format of [Keep a Changelog](https://keepachangelog.com/) is added at the bottom of the PR description. - [x] **Documentation:** Have you updated relevant documentation [Open WebUI Docs](https://github.com/open-webui/docs), or other documentation sources? - [x] **Dependencies:** Are there any new dependencies? Have you updated the dependency versions in the documentation? - [ ] (tested locally) **Testing:** Have you written and run sufficient tests to validate the changes? - [x] **Code review:** Have you performed a self-review of your code, addressing any coding standard issues and ensuring adherence to the project's coding standards? - [x] **Prefix:** To clearly categorize this pull request, prefix the pull request title using one of the following: - **BREAKING CHANGE**: Significant changes that may affect compatibility - **build**: Changes that affect the build system or external dependencies - **ci**: Changes to our continuous integration processes or workflows - **chore**: Refactor, cleanup, or other non-functional code changes - **docs**: Documentation update or addition - **feat**: Introduces a new feature or enhancement to the codebase - **fix**: Bug fix or error correction - **i18n**: Internationalization or localization changes - **perf**: Performance improvement - **refactor**: Code restructuring for better maintainability, readability, or scalability - **style**: Changes that do not affect the meaning of the code (white space, formatting, missing semi-colons, etc.) - **test**: Adding missing tests or correcting existing tests - **WIP**: Work in progress, a temporary label for incomplete or ongoing work # Changelog Entry ### Description - [Concisely describe the changes made in this pull request, including any relevant motivation and impact (e.g., fixing a bug, adding a feature, or improving performance)] ### Added - [List any new features, functionalities, or additions] ### Changed - [List any changes, updates, refactorings, or optimizations] ### Deprecated - [List any deprecated functionality or features that have been removed] ### Removed - [List any removed features, files, or functionalities] ### Fixed - [List any fixes, corrections, or bug fixes] ### Security - [List any new or updated security-related changes, including vulnerability fixes] ### Breaking Changes - **BREAKING CHANGE**: [List any breaking changes affecting compatibility or functionality] --- ### Additional Information - [Insert any additional context, notes, or explanations for the changes] - [Reference any related issues, commits, or other relevant information] ### Screenshots or Videos - [Attach any relevant screenshots or videos demonstrating the changes] ### Contributor License Agreement By submitting this pull request, I confirm that I have read and fully agree to the [Contributor License Agreement (CLA)](/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 07:14:54 -05:00

GiteaMirror closed this issue

2026-05-06 07:14:57 -05:00

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Reference: github-starred/open-webui#62831