Fetcher integration: all API paths, DTOs, headers, and mock are misaligned with real Fetcher contract

[gandalf-at-lerian]

Summary

The Matcher's Fetcher HTTP client (internal/discovery/adapters/fetcher/client.go + types.go) is 100% misaligned with the real Fetcher API. 5 of 6 routes return 404, required headers are never sent, and DTOs silently parse into empty/wrong values. E2E tests pass because the mock (tests/e2e/mock/fetcher_server.go) mirrors the Matcher's expectations, not the real Fetcher.

Route mismatches (all return 404 in prod)

Matcher calls	Fetcher actual
GET /api/v1/connections	GET /v1/management/connections
GET /api/v1/connections/{id}/schema	GET /v1/management/connections/:id/schema
POST /api/v1/connections/{id}/test	POST /v1/management/connections/:id/test
POST /api/v1/extractions	POST /v1/fetcher
GET /api/v1/extractions/{jobId}	GET /v1/fetcher/:id

Only GET /health is correct.

Missing headers

• X-Organization-Id (required on ALL protected routes) — never sent
• X-Product-Name (required on CreateConnection, optional on List) — never sent
• The ?orgId= query param sent in ListConnections is ignored by the Fetcher

DTO mismatches

ListConnections

Fetcher returns {"items": [...], "page", "limit", "total"} (Pagination). Matcher expects {"connections": [...]}. Result: always empty list.

ConnectionResponse

Matcher reads databaseType → Fetcher sends type. Field always empty.

TestConnection

Fetcher returns {status (string), message, latencyMs}. Matcher expects {connectionId, healthy (bool), latencyMs, errorMessage}. The validateFetcherResourceID check always fails because connectionId is absent.

Schema

Fetcher returns id (not connectionId), tables use name (not tableName), columns are fields []string (not columns []{name,type,nullable}). ID validation always fails.

Extraction submit

Completely different contracts. Matcher sends {connectionId, tables}. Fetcher expects {dataRequest: {mappedFields: {datasource: {table: [fields]}}}}.

Extraction status

Fetcher returns id (not jobId). Status values differ: Fetcher uses processing/completed (lowercase), Matcher expects RUNNING/COMPLETE.

Health check

Fetcher returns plain text "healthy". Matcher tries JSON parse {"status": "healthy"} → always fails → IsHealthy() = false.

Mock vs Real Fetcher

The mock server (tests/e2e/mock/fetcher_server.go) uses the same wrong routes and wrong DTOs as the client. Tests are green but prod is 100% broken.

Files to fix

1. internal/discovery/adapters/fetcher/client.go — routes, headers, request building
2. internal/discovery/adapters/fetcher/types.go — all DTOs
3. internal/discovery/adapters/fetcher/config.go — health check plain text handling
4. tests/e2e/mock/fetcher_server.go — align with real Fetcher contract

Context

Found during Console ↔ Matcher ↔ Fetcher integration work by @augustoalvarenga.

Full field-by-field audit report available on request.