First real port of the MCP chassis library — abort-criterion check for
spike S3 of the 2026-05 homelab architecture review.
Changes:
- Drop internal/auth/jwt.go (~79 LOC) — chassis provides JWTValidator
with identical signature.
- Drop internal/auth/bearer.go (~42 LOC) — chassis BearerMiddleware
has the same static-or-JWT semantics plus an optional WWW-Authenticate
resource_metadata challenge (consumed via new resourceMetadataURL arg).
- Drop internal/auth/bearer_test.go — same scenarios are covered in
the chassis bearer_test.go now.
- main.go: import chassis as `chassisauth`, build resourceMetadataURL
only when both DexIssuerURL + MCPResourceURL are set, replace the
inline /.well-known/oauth-protected-resource handler with the chassis
ProtectedResourceHandler.
internal/auth/caller.go (oauth2-proxy header → context) stays — chassis
out-of-scope.
Net LOC change: -~150 LOC duplicated infra + a 5-LOC import.
go.mod gains gitea.d-ma.be/mathias/mcp-chassis v0.1.0 (jwx/v2 + testify
already transitive, no new top-level deps).
Verifies abort criterion: one PR, one binary's worth of port, task check
green (lint + test + vet + govulncheck clean). Per the S3 spike spec,
this clears the chassis to continue. Next port: hyperguild/ingestion
(brain-mcp), filed as a follow-up.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- internal/auth/jwt.go: JWTValidator via lestrrat-go/jwx/v2, JWKS auto-refresh
- internal/auth/bearer.go: replace Gitea PAT validation with JWT->static->default chain
- internal/gitea/client.go: always use service PAT; remove TokenFromContext lookup
- internal/config/config.go: add DexIssuerURL, MCPAudience, MCPResourceURL, StaticToken
- cmd/gitea-mcp/main.go: wire validator, fix /.well-known to return real AS list
- bearer_test.go: rewrite for new API
Shared LRU avoids repeated Gitea calls for default-branch resolution;
the simple stdlib map alternative would race on concurrent access without
a mutex per entry, which is more code than the LRU.
Add internal/config package with Config struct and Load() function.
Reads GITEA_BASE_URL, GITEA_API_TOKEN, GITEA_MCP_ALLOWED_OWNERS,
GITEA_MCP_ORIGIN_ALLOWLIST, GITEA_MCP_PORT with sensible defaults.
Wire cfg.Port into main.go. TDD: tests written first, then impl.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
