Files
galaxy-game/gateway/internal/restapi/admin_proxy.go
T
Ilia Denisov 27916bbe61
Tests · Go / test (push) Successful in 2m0s
feat(admin-console): Stage 1 — pipe + skeleton behind the gateway
Add the server-rendered operator console at /_gm, exposed publicly through
the gateway behind the existing admin_accounts Basic Auth.

Backend:
- new internal/adminconsole package (html/template Renderer, stateless HMAC
  CSRF signer, embedded stylesheet)
- /_gm route group reusing basicauth.Middleware(admin.Service) + a CSRF guard
  (per-operator token + same-origin check); dashboard landing page
- BACKEND_ADMIN_CONSOLE_CSRF_KEY config (per-process random fallback)

Gateway:
- new "admin" public route class (per-IP rate limit, body + GET/HEAD/POST
  method limits) classifying /_gm traffic
- reverse proxy to the backend /_gm surface, preserving Host and relaying the
  backend 401 Basic Auth challenge; 502 when the backend is unreachable
- GATEWAY_PUBLIC_HTTP_ANTI_ABUSE_ADMIN_* config

dev-deploy:
- Caddy routes /_gm/* to the gateway
- bootstrap admin + stable CSRF key; enable Prometheus /metrics exporters on
  backend and gateway (forward-compat for a future Prometheus/Grafana stack)

Docs: ARCHITECTURE 14.1/16, FUNCTIONAL 10.2.1 (+ru mirror), backend and
gateway READMEs, new backend/docs/admin-console.md.

Tests: renderer + CSRF unit tests; backend router auth/render/asset/CSRF;
gateway classifier, proxy forwarding/Host/401/405/413/429/502.
2026-05-31 19:50:15 +02:00

50 lines
1.7 KiB
Go

package restapi
import (
"fmt"
"net/http"
"net/http/httputil"
"net/url"
"go.uber.org/zap"
)
// NewBackendConsoleProxy builds the reverse proxy that forwards operator
// console traffic (`/_gm` and `/_gm/*`) to the backend at backendBaseURL.
//
// The proxy is intentionally thin: it preserves the inbound request path and
// the inbound Host header — the latter so the backend's same-origin CSRF check
// observes the public host rather than the internal upstream — and relays the
// backend response unchanged, including its 401 Basic Auth challenge. It
// answers 502 when the backend is unreachable. Authentication, rendering, and
// every state change live in the backend; the gateway contributes only the
// public anti-abuse layer that runs ahead of this handler.
func NewBackendConsoleProxy(backendBaseURL string, logger *zap.Logger) (http.Handler, error) {
target, err := url.Parse(backendBaseURL)
if err != nil {
return nil, fmt.Errorf("parse backend base URL %q: %w", backendBaseURL, err)
}
if target.Scheme == "" || target.Host == "" {
return nil, fmt.Errorf("backend base URL %q must be absolute", backendBaseURL)
}
if logger == nil {
logger = zap.NewNop()
}
logger = logger.Named("admin_console_proxy")
return &httputil.ReverseProxy{
Rewrite: func(pr *httputil.ProxyRequest) {
pr.SetURL(target)
// SetURL clears Out.Host so the target host is used; restore the
// inbound Host so the backend sees the public origin.
pr.Out.Host = pr.In.Host
},
ErrorHandler: func(w http.ResponseWriter, r *http.Request, err error) {
logger.Warn("admin console upstream error",
zap.String("path", r.URL.Path), zap.Error(err))
w.WriteHeader(http.StatusBadGateway)
},
}, nil
}