Enable Copilot BYOK provider-env fallback, base-path routing, and hardened token isolation by Copilot · Pull Request #2598 · github/gh-aw-firewall

Copilot · 2026-05-05T22:32:51Z

Copilot BYOK runs could fail when workflows set COPILOT_PROVIDER_API_KEY/COPILOT_PROVIDER_BASE_URL without COPILOT_API_KEY: AWF did not activate Copilot sidecar BYOK routing, while one-shot token isolation still replaced the real key with a placeholder. This change aligns key/target/base-path resolution with provider-style envs so sidecar activation and upstream routing remain coherent.

Copilot key resolution fallback
- src/cli.ts now resolves copilotApiKey from:
  - COPILOT_API_KEY
  - fallback: COPILOT_PROVIDER_API_KEY
- This ensures BYOK sidecar paths activate even when only provider key env is present.
Copilot target derivation from provider base URL
- When --copilot-api-target and COPILOT_API_TARGET are unset, CLI derives copilotApiTarget from COPILOT_PROVIDER_BASE_URL hostname.
- The resolved target is used consistently for runtime config and API-target allowlist resolution.
Copilot base-path derivation and propagation from provider base URL
- CLI now derives copilotApiBasePath from the path component of COPILOT_PROVIDER_BASE_URL (or uses COPILOT_API_BASE_PATH when explicitly set).
- src/services/api-proxy-service.ts now forwards COPILOT_API_BASE_PATH to the sidecar.
- containers/api-proxy/providers/copilot.js now applies the base path via getBasePath() so BYOK providers using prefixed endpoints (for example /api/v1) are routed correctly instead of being sent to host root.
Agent token isolation hardening (feedback follow-up)
- When --enable-api-proxy is enabled, agent env passthrough now explicitly excludes:
  - COPILOT_GITHUB_TOKEN
  - COPILOT_API_KEY
  - COPILOT_PROVIDER_API_KEY
- This prevents real Copilot auth credentials from being injected into the agent container via inherited env passthrough (including --env-all), while preserving explicit placeholder behavior used for compatibility.
Focused unit coverage
- Added cli tests for:
  - key precedence/fallback (COPILOT_API_KEY over COPILOT_PROVIDER_API_KEY)
  - hostname derivation from provider base URL (path/port/IPv4/IPv6/invalid input cases)
  - base-path derivation from provider base URL
  - provider-derived routing resolution (target + base path) used for runtime wiring
- Added agent-service tests to verify:
  - provider auth key is not forwarded into agent env when api-proxy is enabled with --env-all
  - Copilot/provider placeholder values remain in place when BYOK config is active
- Added api-proxy tests to verify:
  - COPILOT_API_BASE_PATH is forwarded by compose generation when configured
  - Copilot adapter normalizes and uses configured base path

copilotApiKey: process.env.COPILOT_API_KEY || process.env.COPILOT_PROVIDER_API_KEY;

const { copilotApiTarget, copilotApiBasePath } = resolveCopilotApiRouting(
  { copilotApiTarget: options.copilotApiTarget },
  process.env
);

Agent-Logs-Url: https://github.com/github/gh-aw-firewall/sessions/c315ed17-8485-4fdc-b190-f183211c8c4e

lpcox · 2026-05-05T22:44:11Z

@copilot make sure that auth tokens are never injected into the agent container

github-actions · 2026-05-05T22:44:31Z

✅ Coverage Check Passed

Overall Coverage

Metric	Base	PR	Delta
Lines	86.76%	86.88%	📈 +0.12%
Statements	86.70%	86.82%	📈 +0.12%
Functions	81.22%	81.39%	📈 +0.17%
Branches	79.45%	79.63%	📈 +0.18%

📁 Per-file Coverage Changes (3 files)

File	Lines (Before → After)	Statements (Before → After)
`src/services/agent-service.ts`	95.5% → 95.6% (+0.05%)	95.3% → 95.3% (+0.05%)
`src/container-lifecycle.ts`	87.1% → 88.2% (+1.14%)	87.5% → 88.6% (+1.11%)
`src/cli.ts`	28.1% → 31.6% (+3.49%)	28.1% → 32.0% (+3.93%)

Coverage comparison generated by scripts/ci/compare-coverage.ts

Copilot

Pull request overview

This PR updates the CLI’s Copilot BYOK env resolution so workflows that only set provider-style Copilot env vars can still activate the API proxy sidecar and derive a Copilot target for allowlisting/routing.

Changes:

Added resolveCopilotApiKey() to fall back from COPILOT_API_KEY to COPILOT_PROVIDER_API_KEY.
Added deriveCopilotApiTargetFromProviderBaseUrl() and threaded its result into CLI config + allowlist resolution.
Added unit tests for env precedence and hostname derivation edge cases.

Show a summary per file

File	Description
`src/cli.ts`	Adds Copilot BYOK env fallback helpers and uses the resolved target/key in CLI runtime config and allowlist setup.
`src/cli.test.ts`	Adds focused helper tests for Copilot env-key precedence and provider-base-URL hostname derivation.

Copilot's findings

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Files reviewed: 2/2 changed files
Comments generated: 2

+  const candidate = trimmed.includes('://')
+    ? trimmed
+    : `https://${trimmed}`;
+
+  try {
+    return new URL(candidate).hostname || undefined;


+      options.copilotApiTarget ||
+      process.env.COPILOT_API_TARGET ||
+      copilotApiTargetFromProviderBaseUrl;
+


lpcox · 2026-05-05T22:46:38Z

@copilot address review feedback

Agent-Logs-Url: https://github.com/github/gh-aw-firewall/sessions/1e52e3c6-337c-4588-8305-b0e72820b0bd

Copilot · 2026-05-05T22:50:53Z

@copilot make sure that auth tokens are never injected into the agent container

Implemented in 48e065b. I hardened agent env filtering so COPILOT_GITHUB_TOKEN, COPILOT_API_KEY, and COPILOT_PROVIDER_API_KEY are excluded from passthrough when --enable-api-proxy is on, and added tests that verify real Copilot/provider tokens are not injected into the agent (including --env-all cases).

Agent-Logs-Url: https://github.com/github/gh-aw-firewall/sessions/c8f6f147-e35a-4e96-a440-2a314f3ce5b8

Copilot · 2026-05-05T22:58:10Z

@copilot address review feedback

Addressed in 9d0cb5d. I implemented Copilot provider base-path routing so COPILOT_PROVIDER_BASE_URL paths (for example /api/v1) are preserved via COPILOT_API_BASE_PATH, wired this through CLI/config/api-proxy env, and added regression coverage for routing resolution plus target/base-path propagation.

github-actions · 2026-05-05T23:03:55Z

Smoke Test Results
✅ GitHub MCP: Last 2 merged PRs retrieved
✅ Playwright: github.com title verified
✅ File Writing: Test file created
✅ Bash: File verified

Status: PASS

💥 [THE END] — Illustrated by Smoke Claude

github-actions · 2026-05-05T23:04:11Z

Smoke Test: Copilot BYOK — PR by @Copilot, assignees: @lpcox @Copilot

Test	Result
GitHub MCP connectivity	✅
GitHub.com HTTP	⚠️ pre-step data unavailable (template vars not expanded)
File write/read	⚠️ pre-step data unavailable (template vars not expanded)
BYOK inference (api-proxy → api.githubcopilot.com)	✅

Running in BYOK offline mode (COPILOT_OFFLINE=true) via api-proxy → api.githubcopilot.com.

Overall: PASS (core BYOK path confirmed working)

🔑 BYOK report filed by Smoke Copilot BYOK

github-actions · 2026-05-05T23:04:43Z

🔥 Smoke Test Results

Test	Status
GitHub MCP connectivity	✅
GitHub.com HTTP connectivity	✅
File write/read	✅

Overall: PASS

PR: Enable Copilot BYOK provider-env fallback, base-path routing, and hardened token isolation
Author: @Copilot | Assignees: @lpcox @Copilot

📰 BREAKING: Report filed by Smoke Copilot

github-actions · 2026-05-05T23:04:45Z

🔮 Codex smoke oracle: FAIL
Merged PRs: api-proxy: inject X-Initiator: agent default on all Copilot-bound requests to prevent billing inflation | refactor(entrypoint): deduplicate signal-handler + token-cleanup into shared function
Queried PRs: feat(api-proxy): OIDC authentication for Azure OpenAI (Entra-only) | Enable Copilot BYOK provider-env fallback, base-path routing, and hardened token isolation
✅ GitHub PR review/query, Playwright, file/bash, discussion comment, npm build
❌ safeinputs-gh unavailable; github-discussion-query unavailable; Tavily exposed no callable search tool
Overall status: FAIL

Warning

Firewall blocked 1 domain

The following domain was blocked by the firewall during workflow execution:

registry.npmjs.org

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "registry.npmjs.org"

See Network Configuration for more information.

🔮 The oracle has spoken through Smoke Codex

github-actions · 2026-05-05T23:06:05Z

🏗️ Build Test Suite Results

Ecosystem	Project	Build/Install	Tests	Status
Bun	elysia	✅	1/1 passed	✅ PASS
Bun	hono	✅	1/1 passed	✅ PASS
C++	fmt	✅	N/A	✅ PASS
C++	json	✅	N/A	✅ PASS
Deno	oak	N/A	1/1 passed	✅ PASS
Deno	std	N/A	1/1 passed	✅ PASS
.NET	hello-world	✅	N/A	✅ PASS
.NET	json-parse	✅	N/A	✅ PASS
Go	color	✅	1/1 passed	✅ PASS
Go	env	✅	1/1 passed	✅ PASS
Go	uuid	✅	1/1 passed	✅ PASS
Java	gson	✅	1/1 passed	✅ PASS
Java	caffeine	✅	1/1 passed	✅ PASS
Node.js	clsx	✅	All passed	✅ PASS
Node.js	execa	✅	All passed	✅ PASS
Node.js	p-limit	✅	All passed	✅ PASS
Rust	fd	✅	1/1 passed	✅ PASS
Rust	zoxide	✅	1/1 passed	✅ PASS

Overall: 8/8 ecosystems passed — ✅ PASS

Generated by Build Test Suite for issue #2598 · ● 545K · ◷

github-actions · 2026-05-05T23:06:37Z

Smoke Test Results

Redis PING: ❌ (no response / timeout)
PostgreSQL pg_isready: ❌ (no response)
PostgreSQL SELECT 1: ❌ (no response / timeout)

Overall: FAIL — host.docker.internal service containers are not reachable from this environment.

🔌 Service connectivity validated by Smoke Services

github-actions · 2026-05-05T23:18:58Z

Chroot Version Comparison — Smoke Test Results

Runtime	Host Version	Chroot Version	Match?
Python	Python 3.12.13	Python 3.12.3	❌ NO
Node.js	v24.14.1	v20.20.2	❌ NO
Go	go1.22.12	go1.22.12	✅ YES

Overall: ❌ Not all tests passed — Python and Node.js versions differ between host and chroot. Go versions match.

Tested by Smoke Chroot

Initial plan

4db3b83

Copilot AI assigned Copilot and lpcox May 5, 2026

Copilot started work on behalf of lpcox May 5, 2026 22:32 View session

Copilot AI linked an issue May 5, 2026 that may be closed by this pull request

BYOK mode fails when only COPILOT_PROVIDER_API_KEY is set (without COPILOT_API_KEY) #2597

Closed

fix: support Copilot BYOK provider env fallbacks

23c76db

Agent-Logs-Url: https://github.com/github/gh-aw-firewall/sessions/c315ed17-8485-4fdc-b190-f183211c8c4e

lpcox marked this pull request as ready for review May 5, 2026 22:43

Copilot AI changed the title ~~[WIP] Fix BYOK mode failure when only COPILOT_PROVIDER_API_KEY is set~~ Enable Copilot BYOK fallback when only provider env vars are set May 5, 2026

lpcox requested a review from Mossaka as a code owner May 5, 2026 22:43

Copilot AI review requested due to automatic review settings May 5, 2026 22:43

Copilot finished work on behalf of lpcox May 5, 2026 22:43

Copilot AI requested a review from lpcox May 5, 2026 22:43

Copilot started reviewing on behalf of lpcox May 5, 2026 22:43 View session

Copilot started work on behalf of lpcox May 5, 2026 22:44 View session