feat: add bounded process metrics and private monitoring endpoint

internal/observability/http_test.go

@@ -0,0 +1,93 @@
+package observability
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/coder/websocket"
+)
+
+func TestWebSocketHandshakeIsNotConnectionLifetime(t *testing.T) {
+	r := NewRegistry()
+	released := make(chan struct{})
+	done := make(chan struct{})
+	h := r.Middleware(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		defer close(done)
+		c, err := websocket.Accept(w, req, nil)
+		if err != nil {
+			return
+		}
+		defer c.CloseNow()
+		<-released
+	}))
+	server := httptest.NewTLSServer(h)
+	defer server.Close()
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	c, _, err := websocket.Dial(ctx, strings.Replace(server.URL, "https://", "wss://", 1)+"/v1/worker/connect", &websocket.DialOptions{HTTPClient: server.Client()})
+	if err != nil {
+		close(released)
+		t.Fatal(err)
+	}
+	defer c.CloseNow()
+	// Dial returns after the upgrade response, while the server handler stays open.
+	deadline := time.Now().Add(time.Second)
+	for !strings.Contains(r.Render(), `orbit_websocket_connections{route="worker_connect"} 1`) {
+		if time.Now().After(deadline) {
+			close(released)
+			t.Fatal("upgrade not observed")
+		}
+		time.Sleep(time.Millisecond)
+	}
+	out := r.Render()
+	close(released)
+	<-done
+	if !strings.Contains(out, `orbit_http_requests_total{method="GET",route="worker_connect",status_class="1xx"} 1`) || !strings.Contains(out, "orbit_http_requests_in_flight 0\n") {
+		t.Fatal("upgrade counted as unfinished HTTP")
+	}
+	// done closes inside the handler; wait for middleware's defer to publish closure.
+	deadline = time.Now().Add(time.Second)
+	for !strings.Contains(r.Render(), `orbit_websocket_connections{route="worker_connect"} 0`) {
+		if time.Now().After(deadline) {
+			t.Fatal("connection gauge leaked")
+		}
+		time.Sleep(time.Millisecond)
+	}
+	if !strings.Contains(r.Render(), `orbit_http_requests_total{method="GET",route="worker_connect",status_class="1xx"} 1`) {
+		t.Fatal("upgrade counted twice")
+	}
+}
+func TestInformationalResponseAndStreamingPreserveHTTP(t *testing.T) {
+	r := NewRegistry()
+	server := httptest.NewServer(r.Middleware(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		w.WriteHeader(103)
+		w.WriteHeader(201)
+		_, _ = io.WriteString(w, "first")
+		if err := http.NewResponseController(w).Flush(); err != nil {
+			panic(err)
+		}
+		_, _ = io.WriteString(w, "second")
+	})))
+	defer server.Close()
+	resp, err := server.Client().Get(server.URL + "/v1/tasks")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	if err != nil || resp.StatusCode != 201 || string(body) != "firstsecond" {
+		t.Fatal("wrapper changed HTTP response", resp.StatusCode, err)
+	}
+	deadline := time.Now().Add(time.Second)
+	for !strings.Contains(r.Render(), `route="tasks",status_class="2xx"} 1`) {
+		if time.Now().After(deadline) {
+			t.Fatal("103 blocked final status metric")
+		}
+		time.Sleep(time.Millisecond)
+	}
+}