feat: expose websocket delivery pressure metrics

server/hdl_websock_test.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"syscall"
+	"testing"
+
+	"github.com/gorilla/websocket"
+)
+
+func TestClassifyWSError(t *testing.T) {
+	tests := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{name: "none", want: "none"},
+		{name: "normal close", err: &websocket.CloseError{Code: websocket.CloseNormalClosure}, want: "close_normal"},
+		{name: "abnormal close", err: &websocket.CloseError{Code: websocket.CloseAbnormalClosure}, want: "close_abnormal"},
+		{name: "timeout", err: &net.OpError{Op: "write", Err: os.ErrDeadlineExceeded}, want: "timeout"},
+		{name: "reset", err: fmt.Errorf("write failed: %w", syscall.ECONNRESET), want: "connection_reset"},
+		{name: "broken pipe", err: fmt.Errorf("write failed: %w", syscall.EPIPE), want: "broken_pipe"},
+		{name: "closed", err: net.ErrClosed, want: "closed"},
+		{name: "eof", err: io.EOF, want: "eof"},
+		{name: "other", err: fmt.Errorf("unknown"), want: "other"},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := classifyWSError(tc.err); got != tc.want {
+				t.Fatalf("classifyWSError()=%q want=%q", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestWebSocketOutboundQueueTiming(t *testing.T) {
+	sess := &Session{proto: WEBSOCK, send: make(chan any, 2)}
+	payload := []byte("message")
+	if !sess.queueOutBytes(payload) {
+		t.Fatal("queueOutBytes rejected payload")
+	}
+
+	queued := <-sess.send
+	sess.observeOutboundDequeue(false)
+	if string(queued.([]byte)) != string(payload) {
+		t.Fatalf("payload=%q want=%q", queued, payload)
+	}
+}