Add NO_PROXY support for corporate firewall environments by Copilot · Pull Request #350 · zereight/gitlab-mcp

Copilot · 2026-02-18T14:29:11Z

HTTP_PROXY/HTTPS_PROXY were supported but NO_PROXY was not, preventing bypass of proxy for self-hosted GitLab instances.

Changes

Core Implementation

Added shouldBypassProxy() in gitlab-client-pool.ts with standard pattern matching:
- Exact hostname/IP (localhost, 192.168.1.1)
- Domain suffix (.internal.com)
- Port-specific (example.com:443)
- Wildcard (*)
- Case-insensitive
Modified createAgentsForUrl() to skip proxy agent creation when host matches NO_PROXY patterns
Added noProxy parameter to GitLabClientPoolOptions interface

Configuration

Environment variable: NO_PROXY
CLI argument: --no-proxy
Passed through getConfig() in index.ts to GitLabClientPool constructor

Usage

{
  "env": {
    "HTTP_PROXY": "http://proxy.corp.com:8080",
    "HTTPS_PROXY": "http://proxy.corp.com:8080",
    "NO_PROXY": "localhost,127.0.0.1,.internal.com,gitlab.mycompany.com"
  }
}

Requests to gitlab.mycompany.com bypass proxy while external requests use it.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

nonexistent-proxy.example.com
- Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node /home/REDACTED/work/gitlab-mcp/gitlab-mcp/build/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

This section details on the original issue you should resolve

<issue_title>Support NO_PROXY settings</issue_title>
<issue_description>This would allow support for those behind corporate firewalls with self-hosted gitlab instances. While there is logic for HTTP_PROXY/HTTPS_PROXY there does not see to be logic for setting NO_PROXY. </issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes Support NO_PROXY settings #348

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

Co-authored-by: zereight <42544600+zereight@users.noreply.github.com>

Fachher · 2026-03-19T17:43:52Z

Simple unset HTTP_PROXY and HTTPS_PROXY will solve the problem.
{ "gitlab": { "command": "npx", "args": ["-y", "@zereight/mcp-gitlab@2.0.33"], "env": { "HTTP_PROXY": "", "HTTPS_PROXY": "", "GITLAB_API_URL": "https://<GITLAB_URL_BASEURL>/api/v4", "GITLAB_PROJECT_ID": "10796,10795,10792", "GITLAB_ALLOWED_PROJECT_IDS": "10796,10795,10792", "GITLAB_READ_ONLY_MODE": "false", "USE_GITLAB_WIKI": "false", "USE_MILESTONE": "false", "USE_PIPELINE": "false" } } }

chatgpt-codex-connector · 2026-03-22T12:38:52Z

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Copilot

Pull request overview

Adds NO_PROXY support so the server can bypass configured HTTP(S) proxies for self-hosted/corporate GitLab hosts while still using proxies for external requests.

Changes:

Implemented noProxy option and shouldBypassProxy() matching in GitLabClientPool, and skip proxy agent creation when matched.
Plumbed NO_PROXY / --no-proxy from index.ts into the client pool.
Added unit + integration tests and documented the new env/CLI options in README.md.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
`gitlab-client-pool.ts`	Adds `noProxy` support and bypass logic during agent creation.
`index.ts`	Reads `NO_PROXY` config and passes it to `GitLabClientPool`.
`README.md`	Documents `HTTP_PROXY` / `HTTPS_PROXY` / `NO_PROXY` usage and patterns.
`test/no-proxy-test.ts`	New NO_PROXY pattern-matching unit tests for agent selection.
`test/no-proxy-integration-test.ts`	New integration tests validating bypass vs proxy usage with mock servers.

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Copilot · 2026-03-22T12:42:44Z

+    // Handle port-specific patterns (e.g., "example.com:8080")
+    const [patternHost, patternPort] = pattern.split(':');
+
+    // If pattern specifies a port, check if it matches
+    if (patternPort && port !== patternPort) {
+      continue;
+    }


shouldBypassProxy() parses NO_PROXY entries with pattern.split(':'), which breaks IPv6 literals (e.g., ::1) and bracketed IPv6+port forms (e.g., [::1]:443). This will cause proxy bypass to fail for IPv6 hosts. Consider parsing port by taking the last : only when the suffix is a numeric port and the host is not an IPv6 literal (or explicitly support [v6]:port syntax).

Copilot · 2026-03-22T12:42:44Z

+/**
+ * NO_PROXY Test Suite
+ * Tests NO_PROXY pattern matching and proxy bypass functionality
+ */
+
+import { describe, test } from 'node:test';
+import assert from 'node:assert';
+import { GitLabClientPool } from '../gitlab-client-pool.js';


These new NO_PROXY unit tests are not currently executed by npm test/npm run test:mock (the test script enumerates specific files). Unless they’re wired into the test scripts, they won’t prevent regressions in CI. Consider adding this file (and the integration test) to the test:mock script or switching to a glob-based tsx --test test/**/*.ts approach.

Copilot · 2026-03-22T12:42:45Z

+/**
+ * NO_PROXY Integration Test
+ * Tests NO_PROXY functionality with mock servers
+ */
+
+import { describe, test, after, before } from 'node:test';
+import assert from 'node:assert';
+import { 
+  launchServer, 
+  findAvailablePort, 
+  cleanupServers, 
+  ServerInstance, 
+  TransportMode,
+  HOST 
+} from './utils/server-launcher.js';
+import { MockGitLabServer, findMockServerPort } from './utils/mock-gitlab-server.js';
+import { CustomHeaderClient } from './clients/custom-header-client.js';
+


This integration test file is not included in the current test:mock/test:all scripts (which run a fixed list of test files). If it’s meant to be part of the automated suite, it should be added to the test scripts; otherwise it’s easy for NO_PROXY behavior to regress without detection.

Initial plan

034ab90

Copilot AI assigned Copilot and zereight Feb 18, 2026

Copilot started work on behalf of zereight February 18, 2026 14:30 View session

Copilot AI and others added 4 commits February 18, 2026 14:34

Implement NO_PROXY support with comprehensive tests

a54bbd9

Co-authored-by: zereight <42544600+zereight@users.noreply.github.com>

Add proxy configuration documentation to README

0a9baa2

Co-authored-by: zereight <42544600+zereight@users.noreply.github.com>

Add comprehensive integration tests for NO_PROXY

a549c53

Co-authored-by: zereight <42544600+zereight@users.noreply.github.com>

Improve integration test clarity per code review feedback

6883d70

Co-authored-by: zereight <42544600+zereight@users.noreply.github.com>

Copilot AI changed the title ~~[WIP] Add support for NO_PROXY settings in configuration~~ Add NO_PROXY support for corporate firewall environments Feb 18, 2026

Copilot AI requested a review from zereight February 18, 2026 14:40

Copilot finished work on behalf of zereight February 18, 2026 14:41

zereight marked this pull request as ready for review March 22, 2026 12:38

Copilot AI review requested due to automatic review settings March 22, 2026 12:38

zereight merged commit 1b701af into main Mar 22, 2026
3 checks passed

Copilot started reviewing on behalf of zereight March 22, 2026 12:39 View session

Copilot AI reviewed Mar 22, 2026

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Add NO_PROXY support for corporate firewall environments#350

Add NO_PROXY support for corporate firewall environments#350
zereight merged 5 commits intomainfrom
copilot/support-no-proxy-settings

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Changes

Usage

I tried to connect to the following addresses, but was blocked by firewall rules:

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Pull request overview

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Copilot AI commented Feb 18, 2026 •

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