## Summary
Auto-generated OpenAPI 3.0.3 spec endpoint (`/api/spec`) and Swagger UI
(`/api/docs`) for the CoreScope API.
## What
- **`cmd/server/openapi.go`** — Route metadata map
(`routeDescriptions()`) + spec builder that walks the mux router to
generate a complete OpenAPI 3.0.3 spec at runtime. Includes:
- All 47 API endpoints grouped by tag (admin, analytics, channels,
config, nodes, observers, packets)
- Query parameter documentation for key endpoints (packets, nodes,
search, resolve-hops)
- Path parameter extraction from mux `{name}` patterns
- `ApiKeyAuth` security scheme for API-key-protected endpoints
- Swagger UI served as a self-contained HTML page using unpkg CDN
- **`cmd/server/openapi_test.go`** — Tests for spec endpoint (validates
JSON structure, required fields, path count, security schemes,
self-exclusion of `/api/spec` and `/api/docs`), Swagger UI endpoint, and
`extractPathParams` helper.
- **`cmd/server/routes.go`** — Stores router reference on `Server`
struct for spec generation; registers `/api/spec` and `/api/docs`
routes.
## Design Decisions
- **Runtime spec generation** vs static YAML: The spec walks the actual
router, so it can never drift from registered routes. Route metadata
(summaries, descriptions, tags, auth flags) is maintained in a parallel
map — the test enforces minimum path count to catch drift.
- **No external dependencies**: Uses only stdlib + existing gorilla/mux.
Swagger UI loaded from unpkg CDN (no vendored assets).
- **Security tagging**: Auth-protected endpoints (those behind
`requireAPIKey` middleware) are tagged with `security: [{ApiKeyAuth:
[]}]` in the spec, matching the actual middleware configuration.
## Testing
- `go test -run TestOpenAPI` — validates spec structure, field presence,
path count ≥ 20, security schemes
- `go test -run TestSwagger` — validates HTML response with swagger-ui
references
- `go test -run TestExtractPathParams` — unit tests for path parameter
extraction
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Co-authored-by: you <you@example.com>
