715 lines
28 KiB
Python
715 lines
28 KiB
Python
"""GitHub Copilot authentication utilities.
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Credential search order (matching Copilot CLI behaviour): 1. COPILOT_GITHUB_TOKEN env var 2.
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GH_TOKEN env var 3. GITHUB_TOKEN env var 4. gh auth token CLI fallback
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"""
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from __future__ import annotations
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import json
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import logging
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import os
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import shutil
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import subprocess
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import threading
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import time
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from pathlib import Path
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from typing import Optional
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from hermes_cli._subprocess_compat import IS_WINDOWS, windows_hide_flags
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logger = logging.getLogger(__name__)
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# OAuth device code flow constants — VS Code's GitHub App client ID.
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# The previous opencode OAuth App ID (Ov23li8tweQw6odWQebz) produces gho_*
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# tokens that cannot be exchanged for Copilot API JWTs (404 on
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# /copilot_internal/v2/token). VS Code's App ID produces ghu_* tokens
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# that support exchange, which is required to access internal-only models
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# (e.g. claude-opus-4.6-1m) and enterprise endpoints.
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# Tested on Individual and Enterprise accounts.
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COPILOT_OAUTH_CLIENT_ID = "Iv1.b507a08c87ecfe98"
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# ghp_ classic PATs are rejected by the Copilot API (gho_ / github_pat_ / ghu_ work).
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_CLASSIC_PAT_PREFIX = "ghp_"
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# Env var search order (matches Copilot CLI)
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COPILOT_ENV_VARS = ("COPILOT_GITHUB_TOKEN", "GH_TOKEN", "GITHUB_TOKEN")
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# Polling constants
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_DEVICE_CODE_POLL_INTERVAL = 5 # seconds
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_DEVICE_CODE_POLL_SAFETY_MARGIN = 3 # seconds
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def validate_copilot_token(token: str) -> tuple[bool, str]:
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"""Validate that a token is usable with the Copilot API."""
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token = token.strip()
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if not token:
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return False, "Empty token"
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if token.startswith(_CLASSIC_PAT_PREFIX):
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return False, (
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"Classic Personal Access Tokens (ghp_*) are not supported by the "
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"Copilot API. Use one of:\n"
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" → `copilot login` or `hermes model` to authenticate via OAuth\n"
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" → A fine-grained PAT (github_pat_*) with Copilot Requests permission\n"
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" → `gh auth login` with the default device code flow (produces gho_* tokens)"
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)
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return True, "OK"
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def resolve_copilot_token() -> tuple[str, str]:
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"""Resolve a GitHub token suitable for Copilot API use.
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Returns (token, source) where source describes where the token came from. Raises ValueError if
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only a classic PAT is available.
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"""
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# 1. Check env vars in priority order
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any_env_var_set = False
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for env_var in COPILOT_ENV_VARS:
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val = os.getenv(env_var, "").strip()
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if val:
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any_env_var_set = True
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valid, msg = validate_copilot_token(val)
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if not valid:
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logger.warning(
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"Token from %s is not supported: %s", env_var, msg
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)
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continue
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return val, env_var
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# 2. Fall back to gh auth token — but ONLY when no Copilot env var was
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# explicitly set. When the user exported GITHUB_TOKEN (even an
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# unsupported classic PAT), their intent is to use *that* token, not
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# to silently substitute one from the gh CLI credential store.
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# Skipping the subprocess here also avoids a slow `gh auth token`
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# call (up to 5s timeout on Windows) on every cold start that scans
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# Copilot auth state — a measurable contributor to the ~14s
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# cold-start stall (#60800). The user can run `copilot login` or
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# set a supported token (gho_*/github_pat_*/ghu_) explicitly.
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if any_env_var_set:
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logger.debug(
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"Copilot env var(s) set but none held a supported token; "
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"skipping `gh auth token` fallback to honor explicit env-var "
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"intent (and avoid the subprocess cost on cold start, #60800)."
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)
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return "", ""
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token = _try_gh_cli_token()
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if token:
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valid, msg = validate_copilot_token(token)
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if not valid:
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raise ValueError(
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f"Token from `gh auth token` is a classic PAT (ghp_*). {msg}"
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)
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return token, "gh auth token"
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return "", ""
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def _gh_cli_candidates() -> list[str]:
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"""Return candidate ``gh`` binary paths, including common Homebrew installs."""
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candidates: list[str] = [c for c in (shutil.which("gh"),) if c]
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for candidate in (
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"/opt/homebrew/bin/gh",
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"/usr/local/bin/gh",
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str(Path.home() / ".local" / "bin" / "gh"),
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):
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if candidate not in candidates and os.path.isfile(candidate) and os.access(candidate, os.X_OK):
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candidates.append(candidate)
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return candidates
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# ``gh auth token`` result cache. The probe shells out to the gh CLI, and when
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# gh has no credential store for this HOME (fresh profile, desktop-spawned
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# backend, CI) it can block for its full 5s subprocess timeout — on keyring /
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# D-Bus prompts rather than returning immediately. Provider inventory builds
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# (``/api/model/options``, ``hermes tools``) probe Copilot auth several times
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# per request, so an uncached miss turns one settings-page load into a 4×5s
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# stall that exceeds the Desktop renderer's 15s IPC budget and paints an error
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# (observed Aug 2026: Models/Providers settings pages timing out on every
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# open). Successes and failures are both cached; a short TTL keeps a freshly
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# run ``gh auth login`` discoverable without restarting the backend.
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_GH_CLI_TOKEN_CACHE_TTL_SECONDS = 300.0
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_gh_cli_token_cache: tuple[float, Optional[str]] | None = None
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def _invalidate_gh_cli_token_cache() -> None:
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"""Reset the ``gh auth token`` probe cache (used by tests and re-auth flows)."""
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global _gh_cli_token_cache
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_gh_cli_token_cache = None
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def _try_gh_cli_token() -> Optional[str]:
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"""Return a token from ``gh auth token`` when the GitHub CLI is available.
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The result (including a miss) is cached for a short TTL — see the cache comment above. Callers
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that just re-authenticated can call ``_invalidate_gh_cli_token_cache()`` to re-probe
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immediately.
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"""
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global _gh_cli_token_cache
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now = time.monotonic()
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if _gh_cli_token_cache is not None and now - _gh_cli_token_cache[0] < _GH_CLI_TOKEN_CACHE_TTL_SECONDS:
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return _gh_cli_token_cache[1]
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token = _probe_gh_cli_token()
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_gh_cli_token_cache = (now, token)
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return token
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def _probe_gh_cli_token() -> Optional[str]:
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"""Uncached ``gh auth token`` subprocess probe (see ``_try_gh_cli_token``)."""
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hostname = os.getenv("COPILOT_GH_HOST", "").strip()
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# Build a clean env so gh doesn't short-circuit on GITHUB_TOKEN / GH_TOKEN
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clean_env = {k: v for k, v in os.environ.items()
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if k not in {"GITHUB_TOKEN", "GH_TOKEN"}}
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# Never let gh open an interactive prompt from a backend process.
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clean_env.setdefault("GH_PROMPT_DISABLED", "1")
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clean_env.setdefault("GH_NO_UPDATE_NOTIFIER", "1")
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_popen_kwargs = {"creationflags": windows_hide_flags()} if IS_WINDOWS else {}
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for gh_path in _gh_cli_candidates():
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cmd = [gh_path, "auth", "token"]
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if hostname:
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cmd += ["--hostname", hostname]
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try:
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result = subprocess.run(
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cmd,
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capture_output=True,
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text=True, encoding='utf-8', errors='replace',
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timeout=5,
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env=clean_env,
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stdin=subprocess.DEVNULL,
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**_popen_kwargs,
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)
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except (FileNotFoundError, subprocess.TimeoutExpired) as exc:
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logger.debug("gh CLI token lookup failed (%s): %s", gh_path, exc)
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continue
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if result.returncode == 0 and result.stdout.strip():
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return result.stdout.strip()
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return None
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# ─── OAuth Device Code Flow ────────────────────────────────────────────────
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_DEVICE_CODE_TERMINAL_ERRORS = {
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"expired_token": " ✗ Device code expired. Please try again.",
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"access_denied": " ✗ Authorization was denied.",
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}
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def copilot_device_code_login(
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*,
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host: str = "github.com",
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timeout_seconds: float = 300,
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) -> Optional[str]:
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"""Run the GitHub OAuth device code flow for Copilot."""
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import urllib.request
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import urllib.parse
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domain = host.rstrip("/")
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device_code_url = f"https://{domain}/login/device/code"
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access_token_url = f"https://{domain}/login/oauth/access_token"
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def _post_form(url: str, fields: dict, timeout: float) -> dict:
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req = urllib.request.Request(
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url,
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data=urllib.parse.urlencode(fields).encode(),
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headers={
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"Accept": "application/json",
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"Content-Type": "application/x-www-form-urlencoded",
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"User-Agent": "HermesAgent/1.0",
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},
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)
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with urllib.request.urlopen(req, timeout=timeout) as resp:
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return json.loads(resp.read().decode())
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# Step 1: Request device code
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try:
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device_data = _post_form(
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device_code_url, {"client_id": COPILOT_OAUTH_CLIENT_ID, "scope": "read:user"}, 15
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)
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except Exception as exc:
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logger.error("Failed to initiate device authorization: %s", exc)
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print(f" ✗ Failed to start device authorization: {exc}")
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return None
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verification_uri = device_data.get("verification_uri", "https://github.com/login/device")
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user_code = device_data.get("user_code", "")
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device_code = device_data.get("device_code", "")
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interval = max(device_data.get("interval", _DEVICE_CODE_POLL_INTERVAL), 1)
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if not device_code or not user_code:
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print(" ✗ GitHub did not return a device code.")
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return None
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# Step 2: Show instructions
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print()
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print(f" Open this URL in your browser: {verification_uri}")
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print(f" Enter this code: {user_code}")
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print()
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print(" Waiting for authorization...", end="", flush=True)
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# Step 3: Poll for completion
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deadline = time.monotonic() + timeout_seconds
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while time.monotonic() < deadline:
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time.sleep(interval + _DEVICE_CODE_POLL_SAFETY_MARGIN)
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try:
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result = _post_form(
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access_token_url,
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{
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"client_id": COPILOT_OAUTH_CLIENT_ID,
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"device_code": device_code,
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"grant_type": "urn:ietf:params:oauth:grant-type:device_code",
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},
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10,
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)
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except Exception:
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print(".", end="", flush=True)
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continue
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if result.get("access_token"):
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print(" ✓")
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return result["access_token"]
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error = result.get("error", "")
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if error == "slow_down":
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# RFC 8628: add 5 seconds to polling interval
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server_interval = result.get("interval")
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if isinstance(server_interval, (int, float)) and server_interval > 0:
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interval = int(server_interval)
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else:
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interval += 5
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if error in ("authorization_pending", "slow_down"):
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print(".", end="", flush=True)
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continue
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if error:
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print()
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print(_DEVICE_CODE_TERMINAL_ERRORS.get(error, f" ✗ Authorization failed: {error}"))
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return None
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print()
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print(" ✗ Timed out waiting for authorization.")
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return None
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# ─── Copilot Token Exchange ────────────────────────────────────────────────
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# Module-level cache for exchanged Copilot API tokens.
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# Maps raw_token_fingerprint -> (api_token, expires_at_epoch, base_url).
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_jwt_cache: dict[str, tuple[str, float, Optional[str]]] = {}
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_JWT_REFRESH_MARGIN_SECONDS = 120 # refresh 2 min before expiry
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# Token exchange endpoint and headers (matching VS Code / Copilot CLI)
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_TOKEN_EXCHANGE_URL = "https://api.github.com/copilot_internal/v2/token"
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_EDITOR_VERSION = "vscode/1.104.1"
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_EXCHANGE_USER_AGENT = "GitHubCopilotChat/0.26.7"
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# Transient-failure hardening for the token exchange. Gateway startup often
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# races network readiness (launchd relaunch, DHCP/VPN settling); a single-shot
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# exchange that fails there silently degrades to the RAW GitHub token, which the
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# Copilot server routes to the "copilot-language-server" integrator whose model
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# allowlist omits enterprise-only models (e.g. claude-opus-4.8) → HTTP 400 on
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# every turn until the next restart. Retry a few times, and persist the last
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# good exchanged JWT to disk so a restart during a blip reuses the still-valid
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# ~30-min token instead of degrading.
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_EXCHANGE_MAX_ATTEMPTS = 3
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_EXCHANGE_BACKOFF_BASE_SECONDS = 1.5 # sleeps ~1.5s, ~3.0s between attempts
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_JWT_DISK_FILENAME = ".copilot_jwt.json"
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_JWT_DISK_MAX_BYTES = 1_048_576 # 1 MiB cap on the persisted JWT store read
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# Negative cache for failed exchanges. Without it, every load_pool("copilot")
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# call re-runs the full exchange — and on a permanently-rejected token
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# (HTTP 403: account not Copilot-entitled, expired grant, org policy) the
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# retry backoff burned ~4.5s of time.sleep() on EVERY provider-discovery
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# pass. The /model picker, delegation child spawns, and the web dashboard
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# all walk that path, so a single bad Copilot token made all of them crawl.
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# Maps raw-token fingerprint -> epoch until which exchange attempts are
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# skipped (raise immediately). Success clears the entry.
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_exchange_failure_cache: dict[str, float] = {}
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# Single-flight guard per token fingerprint: concurrent callers (the dashboard
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# polls /api/credentials/pool every few seconds, each poll off-loop) wait on
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# the ONE in-flight exchange and then hit the positive/negative cache, instead
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# of each spawning their own hung resolver thread during a DNS outage.
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_exchange_locks: dict[str, threading.Lock] = {}
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_exchange_locks_guard = threading.Lock()
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def _exchange_lock_for(fp: str) -> threading.Lock:
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with _exchange_locks_guard:
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lock = _exchange_locks.get(fp)
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if lock is None:
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lock = _exchange_locks[fp] = threading.Lock()
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return lock
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_EXCHANGE_FAILURE_TTL_TRANSIENT_SECONDS = 60.0 # network blips: retry soon
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_EXCHANGE_FAILURE_TTL_PERMANENT_SECONDS = 1800.0 # 401/403/404: won't heal
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# HTTP statuses that indicate the token itself is rejected — retrying with
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# backoff is pointless (the retry loop exists for startup network races,
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# not for auth rejections) and sleeping on them just blocks the caller.
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_EXCHANGE_PERMANENT_HTTP_STATUSES = frozenset({401, 403, 404})
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def _token_fingerprint(raw_token: str) -> str:
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"""Short fingerprint of a raw token for cache keying (avoids storing full token)."""
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import hashlib
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return hashlib.sha256(raw_token.encode()).hexdigest()[:16]
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def _read_jwt_store(path: Path) -> Optional[dict]:
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"""Bounded read of the on-disk JWT store → dict, or None if missing/unusable.
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Single chokepoint for every read of the persisted store (load, eviction, save-merge). A well-
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formed store is a few KB; a file over the 1 MiB cap or with non-dict content is treated as
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unusable so a corrupt/oversized file can't balloon memory or get rewritten back out.
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"""
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if not path.exists():
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return None
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try:
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if path.stat().st_size > _JWT_DISK_MAX_BYTES:
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logger.debug(
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"Persisted Copilot JWT store exceeds %d bytes; ignoring", _JWT_DISK_MAX_BYTES
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)
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return None
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loaded = json.loads(path.read_text(encoding="utf-8"))
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return loaded if isinstance(loaded, dict) else None
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except Exception as exc:
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logger.debug("Failed to read persisted Copilot JWT store: %s", exc)
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return None
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def _write_jwt_store(path: Path, store: dict) -> None:
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"""Atomically write the JWT store (tmp + os.replace), best-effort 0o600."""
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tmp = path.with_suffix(path.suffix + ".tmp")
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tmp.write_text(json.dumps(store), encoding="utf-8")
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try:
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os.chmod(tmp, 0o600)
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except Exception:
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pass
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os.replace(tmp, path)
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def evict_cached_exchanged_token(raw_token: str) -> None:
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"""Drop any cached exchanged JWT for ``raw_token`` (in-process + on-disk).
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Used by the runtime stale-credential recovery path: when a live request starts failing with a
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Copilot ``model_not_available_for_integrator`` / ``model_not_supported`` 400, the cached
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exchanged token (or a degraded raw fallback that was cached in its place) is stale.
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"""
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if not raw_token:
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return
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fp = _token_fingerprint(raw_token)
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_jwt_cache.pop(fp, None)
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# Also clear any negative-cache entry: eviction is an explicit "force a
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# fresh exchange" signal from the stale-credential recovery path, so the
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# next exchange_copilot_token() must be allowed to hit the network.
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_exchange_failure_cache.pop(fp, None)
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path = _jwt_disk_path()
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if not path:
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return
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try:
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store = _read_jwt_store(path)
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if store is not None and fp in store:
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del store[fp]
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_write_jwt_store(path, store)
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except Exception as exc:
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logger.debug("Failed to evict cached Copilot JWT: %s", exc)
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def _jwt_disk_path() -> Optional[Path]:
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"""Path to the on-disk exchanged-JWT cache (profile-aware), or None."""
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try:
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from hermes_constants import get_hermes_home
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return Path(get_hermes_home()) / _JWT_DISK_FILENAME
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except Exception:
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return None
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def _load_jwt_from_disk(fp: str) -> Optional[tuple[str, float, Optional[str]]]:
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"""Load a persisted exchanged JWT for ``fp`` → (api_token, expires_at, base_url).
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An oversized/corrupt store is treated as unusable — the caller re-exchanges (bound shared with
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eviction/save via _read_jwt_store).
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"""
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path = _jwt_disk_path()
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if not path:
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return None
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try:
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entry = (_read_jwt_store(path) or {}).get(fp)
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if not isinstance(entry, dict):
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return None
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api_token = entry.get("api_token", "")
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expires_at = float(entry.get("expires_at", 0) or 0)
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if api_token and expires_at:
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return api_token, expires_at, entry.get("base_url")
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except Exception as exc:
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logger.debug("Failed to load persisted Copilot JWT: %s", exc)
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return None
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def _save_jwt_to_disk(
|
||
fp: str, api_token: str, expires_at: float, base_url: Optional[str]
|
||
) -> None:
|
||
"""Persist an exchanged JWT (0o600), pruning expired entries."""
|
||
path = _jwt_disk_path()
|
||
if not path:
|
||
return
|
||
try:
|
||
now = time.time()
|
||
store = {
|
||
k: v
|
||
for k, v in (_read_jwt_store(path) or {}).items()
|
||
if isinstance(v, dict) and float(v.get("expires_at", 0) or 0) > now
|
||
}
|
||
store[fp] = {
|
||
"api_token": api_token,
|
||
"expires_at": expires_at,
|
||
"base_url": base_url,
|
||
}
|
||
_write_jwt_store(path, store)
|
||
except Exception as exc:
|
||
logger.debug("Failed to persist Copilot JWT: %s", exc)
|
||
|
||
|
||
# Hard wall-clock cap for the token-exchange HTTP call. urllib's ``timeout``
|
||
# only bounds socket operations AFTER DNS resolution succeeds; getaddrinfo
|
||
# blocks in C and ignores it entirely, so on a networkless Windows host the
|
||
# resolver can hang for many minutes (observed: a 17-minute event-loop stall
|
||
# on 2026-08-22 that took the whole backend down with it).
|
||
_DNS_GRACE_SECONDS = 5.0
|
||
|
||
|
||
def _urlopen_bounded(req, timeout: float):
|
||
"""urlopen() with a hard wall-clock cap of timeout + _DNS_GRACE_SECONDS.
|
||
|
||
Runs the call on a daemon thread and abandons it if the cap fires, so a
|
||
DNS/getaddrinfo hang cannot block the caller indefinitely. Raises the
|
||
worker's exception, or TimeoutError when the cap fires.
|
||
"""
|
||
import urllib.request
|
||
|
||
box: dict = {}
|
||
abandoned = threading.Event()
|
||
|
||
def _worker() -> None:
|
||
try:
|
||
resp = urllib.request.urlopen(req, timeout=timeout)
|
||
except BaseException as exc: # re-raised on the caller's thread
|
||
box["exc"] = exc
|
||
return
|
||
if abandoned.is_set():
|
||
# The caller already timed out; nobody will read this response,
|
||
# so release its socket instead of leaking it with the thread.
|
||
try:
|
||
resp.close()
|
||
except Exception:
|
||
pass
|
||
return
|
||
box["resp"] = resp
|
||
|
||
t = threading.Thread(
|
||
target=_worker, name="copilot-token-exchange", daemon=True
|
||
)
|
||
t.start()
|
||
t.join(timeout + _DNS_GRACE_SECONDS)
|
||
if t.is_alive():
|
||
abandoned.set()
|
||
raise TimeoutError(
|
||
"copilot token exchange exceeded hard cap of "
|
||
f"{timeout + _DNS_GRACE_SECONDS:.0f}s (DNS/getaddrinfo hang?)"
|
||
)
|
||
if "exc" in box:
|
||
raise box["exc"]
|
||
if "resp" not in box:
|
||
raise TimeoutError("copilot token exchange worker died without result")
|
||
return box["resp"]
|
||
|
||
|
||
def exchange_copilot_token(raw_token: str, *, timeout: float = 10.0) -> tuple[str, float, Optional[str]]:
|
||
"""Exchange a raw GitHub token for a short-lived Copilot API token.
|
||
|
||
The token is a semicolon-separated string (not a JWT) used as a Bearer token. ``base_url`` is
|
||
the account-specific host: the exchange's ``endpoints.api`` (enterprise/proxied accounts), else
|
||
derived from the token's ``proxy-ep``; individual accounts have neither, so it is None. Cached
|
||
in-process until close to expiry. Raises ``ValueError`` on failure.
|
||
"""
|
||
fp = _token_fingerprint(raw_token)
|
||
|
||
# Fast path outside the lock: a valid in-process JWT needs no exchange.
|
||
cached = _jwt_cache.get(fp)
|
||
if cached and time.time() < cached[1] - _JWT_REFRESH_MARGIN_SECONDS:
|
||
return cached
|
||
|
||
with _exchange_lock_for(fp):
|
||
return _exchange_copilot_token_locked(raw_token, fp, timeout=timeout)
|
||
|
||
|
||
def _exchange_copilot_token_locked(
|
||
raw_token: str, fp: str, *, timeout: float
|
||
) -> tuple[str, float, Optional[str]]:
|
||
import urllib.request
|
||
|
||
# Re-check the in-process cache under the lock (a concurrent caller may have
|
||
# just completed the exchange we were queued behind), then the on-disk
|
||
# cache: a fresh process (e.g. gateway restart) has an empty in-process
|
||
# cache but may have a still-valid persisted JWT. Reusing it avoids a
|
||
# network round-trip at startup — precisely when the network is most likely
|
||
# to be flaky and the single-shot exchange would degrade to the raw token.
|
||
for lookup in (_jwt_cache.get, _load_jwt_from_disk):
|
||
cached = lookup(fp)
|
||
if cached and time.time() < cached[1] - _JWT_REFRESH_MARGIN_SECONDS:
|
||
_jwt_cache[fp] = cached
|
||
return cached
|
||
|
||
# Negative cache: a recent exchange failure for this token means the
|
||
# network round-trip (and its retry backoff) would just repeat. Fail
|
||
# fast so provider discovery / picker opens don't block on a token we
|
||
# already know is rejected or unreachable.
|
||
_fail_until = _exchange_failure_cache.get(fp, 0.0)
|
||
if time.time() < _fail_until:
|
||
raise ValueError(
|
||
"Copilot token exchange recently failed; skipping re-attempt "
|
||
f"for another {int(_fail_until - time.time())}s"
|
||
)
|
||
|
||
req = urllib.request.Request(
|
||
_TOKEN_EXCHANGE_URL,
|
||
method="GET",
|
||
headers={
|
||
"Authorization": f"token {raw_token}",
|
||
"User-Agent": _EXCHANGE_USER_AGENT,
|
||
"Accept": "application/json",
|
||
"Editor-Version": _EDITOR_VERSION,
|
||
},
|
||
)
|
||
|
||
# Retry with backoff. Startup network races (launchd relaunch, VPN/DHCP
|
||
# settling) make the first attempt flaky; without this the sole failure
|
||
# silently degrades to the raw token for the whole process lifetime.
|
||
# Permanent HTTP rejections (401/403/404 — token not Copilot-entitled,
|
||
# revoked, or org-blocked) skip the retry loop entirely: backoff exists
|
||
# for transient network races, and sleeping on an auth rejection just
|
||
# blocks the caller for ~4.5s with an identical outcome.
|
||
data = None
|
||
last_exc: Optional[Exception] = None
|
||
permanent_failure = False
|
||
for attempt in range(1, _EXCHANGE_MAX_ATTEMPTS + 1):
|
||
try:
|
||
with _urlopen_bounded(req, timeout) as resp:
|
||
data = json.loads(resp.read().decode())
|
||
break
|
||
except Exception as exc: # noqa: BLE001 — retry all, re-raise below
|
||
last_exc = exc
|
||
status = getattr(exc, "code", None) or getattr(exc, "status", None)
|
||
permanent_failure = status in _EXCHANGE_PERMANENT_HTTP_STATUSES
|
||
if permanent_failure:
|
||
logger.debug("Copilot token exchange rejected (HTTP %s); not retrying", status)
|
||
break
|
||
if attempt < _EXCHANGE_MAX_ATTEMPTS:
|
||
sleep_s = _EXCHANGE_BACKOFF_BASE_SECONDS * attempt
|
||
logger.debug(
|
||
"Copilot token exchange attempt %d/%d failed (%s); retrying in %.1fs",
|
||
attempt, _EXCHANGE_MAX_ATTEMPTS, exc, sleep_s,
|
||
)
|
||
time.sleep(sleep_s)
|
||
if data is None:
|
||
ttl = (
|
||
_EXCHANGE_FAILURE_TTL_PERMANENT_SECONDS
|
||
if permanent_failure
|
||
else _EXCHANGE_FAILURE_TTL_TRANSIENT_SECONDS
|
||
)
|
||
_exchange_failure_cache[fp] = time.time() + ttl
|
||
raise ValueError(
|
||
f"Copilot token exchange failed after {_EXCHANGE_MAX_ATTEMPTS} attempts: {last_exc}"
|
||
) from last_exc
|
||
_exchange_failure_cache.pop(fp, None)
|
||
|
||
api_token = data.get("token", "")
|
||
if not api_token:
|
||
raise ValueError("Copilot token exchange returned empty token")
|
||
expires_at = data.get("expires_at", 0)
|
||
expires_at = float(expires_at) if expires_at else time.time() + 1800
|
||
|
||
# Resolve the account-specific API base URL. GitHub advertises the
|
||
# authoritative endpoint under ``endpoints.api`` in the exchange response
|
||
# (it differs for Copilot Enterprise / proxied accounts). When the
|
||
# response omits it, fall back to deriving the host from the ``proxy-ep``
|
||
# field embedded in the exchanged token. Individual accounts have neither,
|
||
# so ``base_url`` stays None and callers use the registry default.
|
||
endpoints = data.get("endpoints")
|
||
base_url: Optional[str] = (
|
||
str(endpoints.get("api") or "").strip().rstrip("/") if isinstance(endpoints, dict) else ""
|
||
) or _derive_base_url_from_proxy_ep(api_token)
|
||
|
||
_jwt_cache[fp] = (api_token, expires_at, base_url)
|
||
_save_jwt_to_disk(fp, api_token, expires_at, base_url)
|
||
logger.debug(
|
||
"Copilot token exchanged, expires_at=%s, base_url=%s",
|
||
expires_at,
|
||
base_url,
|
||
)
|
||
return api_token, expires_at, base_url
|
||
|
||
|
||
def _derive_base_url_from_proxy_ep(token: str) -> Optional[str]:
|
||
"""Derive the Copilot API base URL from a proxy-ep field in the token.
|
||
|
||
The token looks like ``tid=…;exp=…;proxy-ep=proxy.enterprise.githubcopilot.com;…``; the API host
|
||
is that value with the leading ``proxy.`` replaced by ``api.``. None if proxy-ep is absent.
|
||
"""
|
||
import re
|
||
m = re.search(r'(?:^|;)\s*proxy-ep=([^;\s]+)', token)
|
||
if not m:
|
||
return None
|
||
|
||
# Strip scheme if present
|
||
proxy_ep = re.sub(r"^https?://", "", m.group(1), count=1).rstrip("/")
|
||
|
||
# Replace leading "proxy." with "api."
|
||
if proxy_ep.startswith("proxy."):
|
||
proxy_ep = "api." + proxy_ep[len("proxy."):]
|
||
return f"https://{proxy_ep}"
|
||
|
||
|
||
def get_copilot_api_token(raw_token: str) -> tuple[str, Optional[str]]:
|
||
"""Exchange a raw GitHub token for a Copilot API token, with fallback.
|
||
|
||
Convenience wrapper: returns ``(api_token, base_url)`` on success, or ``(raw_token, None)`` if
|
||
the exchange fails (e.g. network error, unsupported account type). This preserves existing
|
||
behaviour for accounts that don't need exchange while enabling access to internal-only models
|
||
for those that do.
|
||
|
||
``base_url`` is the account-specific API endpoint advertised by the exchange (``endpoints.api``,
|
||
with a ``proxy-ep`` fallback), or None for individual accounts.
|
||
"""
|
||
if not raw_token:
|
||
return raw_token, None
|
||
try:
|
||
api_token, _, base_url = exchange_copilot_token(raw_token)
|
||
return api_token, base_url
|
||
except Exception as exc:
|
||
logger.debug("Copilot token exchange failed, using raw token: %s", exc)
|
||
return raw_token, None
|
||
|
||
|
||
# ─── Copilot API Headers ───────────────────────────────────────────────────
|
||
|
||
def copilot_request_headers(
|
||
*,
|
||
is_agent_turn: bool = True,
|
||
is_vision: bool = False,
|
||
) -> dict[str, str]:
|
||
"""Build the standard headers for Copilot API requests."""
|
||
headers: dict[str, str] = {
|
||
"Editor-Version": _EDITOR_VERSION,
|
||
"User-Agent": "HermesAgent/1.0",
|
||
"Copilot-Integration-Id": "vscode-chat",
|
||
"Openai-Intent": "conversation-edits",
|
||
"x-initiator": "agent" if is_agent_turn else "user",
|
||
}
|
||
if is_vision:
|
||
headers["Copilot-Vision-Request"] = "true"
|
||
|
||
return headers
|