implement grpc gateway and addl handler support

pkg/srv/http/http.go

@@ -57,6 +57,15 @@ func prepHTTPServer(opts *opts.AppHTTP) *http.Server {
 			Msg("mounted prometheus metrics endpoint")
 	}
 
+	// Inject extra handlers if given
+	// Used for grpc-gateway runtime.ServeMux handlers
+	for _, h := range opts.Handlers {
+		if h.StripPrefix {
+			h.Handler = http.StripPrefix(h.Prefix, h.Handler)
+		}
+		mux.Handle(h.Prefix, h.Handler)
+	}
+
 	// Add OTEL, skip health-check spans
 	// NOTE: Add any other span exclusions here
 	handler := otelhttp.NewHandler(mux, "/",

pkg/srv/http/opts/http_config.go

@@ -8,8 +8,9 @@ import (
 
 type AppHTTP struct {
 	Ctx            context.Context
-	Funcs          []HTTPFunc
-	Middleware     []http.Handler
+	Funcs          []HTTPFunc     // Handler funcs, will be wrapped with OTEL
+	Middleware     []http.Handler // Middleware (e.g. request logging)
+	Handlers       []HTTPHandler  // Raw Handler/Mux to add, optional prefix stripping
 	HealthChecks   []HealthCheckFunc
 	CustomListener net.Listener
 	HTTPDone       <-chan any
@@ -20,4 +21,10 @@ type HTTPFunc struct {
 	HandlerFunc http.HandlerFunc
 }
 
+type HTTPHandler struct {
+	Prefix      string // path prefix under which to serve this handler/mux
+	StripPrefix bool   // strip path before sending to handler/mux
+	Handler     http.Handler
+}
+
 type HealthCheckFunc func(context.Context) error