Declarative: GitHub App authentication (installation token with JWT)

[devin-ai-integration]

Problem

GitHub Apps provide higher rate limits than Personal Access Tokens (PATs), but implementing GitHub App authentication requires custom Python code. This prevents connectors from being fully declarative (manifest-only).

Rate Limit Comparison

• PAT: 5,000 requests/hour
• OAuth App: 5,000 requests/hour (15,000 if owned by Enterprise Cloud org)
• GitHub App (non-Enterprise): 5,000-12,500 requests/hour (scales with repos/users)
• GitHub App (Enterprise Cloud): 15,000 requests/hour (3x PAT limit)

Current Workaround

Connectors like source-github only support PAT and OAuth authentication. See source-github/spec.json:16-65 which only exposes OAuth and PAT options.

GitHub App authentication is not supported because it requires a two-step flow:

1. Sign a JWT using App ID + private key
2. Exchange JWT for installation access token via POST /app/installations/{installation_id}/access_tokens
3. Cache and refresh the installation token before ~1 hour expiry

Proposed Solution

Option 1: Extend SessionTokenAuthenticator to support GitHub App flow

• Use JwtAuthenticator for the JWT signing step
• Configure login_requester to call the installation token endpoint with JWT header
• Set expiration_duration to ~1 hour for token caching

Option 2: Create dedicated GitHubAppAuthenticator component

• Accepts app_id, installation_id, and private_key
• Handles JWT signing and installation token exchange internally
• Automatically refreshes tokens before expiry

Example Configuration (Option 1)

authenticator:
  type: SessionTokenAuthenticator
  login_requester:
    type: HttpRequester
    url_base: "https://api.github.com"
    path: "/app/installations/{{ config.installation_id }}/access_tokens"
    http_method: "POST"
    authenticator:
      type: JwtAuthenticator
      secret_key: "{{ config.private_key }}"
      algorithm: "RS256"
      token_duration: 600  # 10 minutes
      jwt_payload:
        iss: "{{ config.app_id }}"
        iat: "{{ now_utc() }}"
        exp: "{{ now_utc() + 600 }}"
  session_token_path: ["token"]
  expiration_duration: "PT1H"  # 1 hour
  request_authentication:
    type: BearerAuthenticator
    api_token: "{{ session_token }}"

Example Configuration (Option 2)

authenticator:
  type: GitHubAppAuthenticator
  app_id: "{{ config.app_id }}"
  installation_id: "{{ config.installation_id }}"
  private_key: "{{ config.private_key }}"

Impact

This would enable connectors like source-github, source-gitlab (which also supports GitLab Apps), and others to leverage higher rate limits without custom Python code.

Related

• Survey of Manifest-Only Connectors Using Custom Components (Feature Gaps) #714 - Survey showing 74.3% of certified manifest-only connectors require custom components
• Requested by Aaron ("AJ") Steers (@aaronsteers) in https://airbytehq-team.slack.com/archives/C08BHPUMEPJ/p1762665961303909
• GitHub Docs: Rate limits for the REST API

Code References

• source-github/spec.json:16-65 - Current auth options (OAuth and PAT only)
• source-github/source.py:118-135 - get_access_token() implementation
• Declarative schema already has JwtAuthenticator and SessionTokenAuthenticator which could potentially be composed for this use case