test(webview): cover event stream failures and cleanup

internal/webview/rpcprovider/events_test.go

@@ -2,9 +2,11 @@ package rpcprovider
 
 import (
 	"encoding/json"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -85,3 +87,121 @@ func TestPageEventStream(t *testing.T) {
 		t.Fatal("registration after close")
 	}
 }
+
+func TestPageEventStreamHandshakeFailureCanRetry(t *testing.T) {
+	for _, tc := range []struct {
+		name   string
+		status int
+		body   string
+	}{
+		{"http_error", http.StatusUnauthorized, `{"ready":true}`},
+		{"invalid_json", http.StatusOK, `not json`},
+		{"not_ready", http.StatusOK, `{"ready":false}`},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			var requests atomic.Int32
+			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				if requests.Add(1) == 1 {
+					w.WriteHeader(tc.status)
+					_, _ = io.WriteString(w, tc.body)
+					return
+				}
+				_, _ = io.WriteString(w, "{\"ready\":true}\n{\"event\":\"load\",\"data\":{\"url\":\"https://example.test\"}}\n")
+				w.(http.Flusher).Flush()
+				<-r.Context().Done()
+			}))
+			defer server.Close()
+			p := &page{client: NewClient(wv.RPCConfig{Network: "tcp", Address: strings.TrimPrefix(server.URL, "http://")}), id: "retry-page"}
+			if off, err := p.On("load", func(wv.Event) { t.Error("failed registration retained its listener") }); err == nil || off != nil {
+				t.Fatal("failed handshake accepted")
+			}
+			got := make(chan wv.Event, 1)
+			off, err := p.On("load", func(e wv.Event) { got <- e })
+			if err != nil {
+				t.Fatalf("retry: %v", err)
+			}
+			defer func() {
+				p.eventCancel()
+				<-p.eventDone
+			}()
+			defer off()
+			select {
+			case e := <-got:
+				if e.Data["url"] != "https://example.test" {
+					t.Fatal(e)
+				}
+			case <-time.After(time.Second):
+				t.Fatal("retry did not receive load notification")
+			}
+			if requests.Load() != 2 {
+				t.Fatalf("unexpected request count: %d", requests.Load())
+			}
+		})
+	}
+}
+
+func TestPageEventStreamDisconnectAndClose(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var request wv.RPCRequest
+		if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
+			t.Error(err)
+			return
+		}
+		switch request.Method {
+		case wv.MethodPageEvents:
+			// End the stream without a terminal event, as if the host dropped it.
+			_, _ = io.WriteString(w, "{\"ready\":true}\n")
+		case wv.MethodPageClose:
+			_ = json.NewEncoder(w).Encode(wv.RPCResponse{})
+		default:
+			t.Errorf("unexpected method: %s", request.Method)
+		}
+	}))
+	defer server.Close()
+	p := &page{client: NewClient(wv.RPCConfig{Network: "tcp", Address: strings.TrimPrefix(server.URL, "http://")}), id: "disconnected-page"}
+	closed := make(chan wv.Event, 1)
+	if _, err := p.On("closed", func(e wv.Event) { closed <- e }); err != nil {
+		t.Fatal(err)
+	}
+	select {
+	case <-p.eventDone:
+	case <-time.After(time.Second):
+		t.Fatal("disconnected stream did not stop")
+	}
+	if _, err := p.On("load", func(wv.Event) {}); err == nil || !strings.Contains(err.Error(), "disconnected") {
+		t.Fatalf("registration hid stream failure: %v", err)
+	}
+	if err := p.Close(); err != nil {
+		t.Fatal(err)
+	}
+	select {
+	case event := <-closed:
+		if event.Data["reason"] != "api" {
+			t.Fatal(event)
+		}
+	default:
+		t.Fatal("API close did not release listeners after disconnect")
+	}
+	if err := p.Close(); err != nil {
+		t.Fatal(err)
+	}
+	select {
+	case event := <-closed:
+		t.Fatalf("duplicate close notification: %+v", event)
+	default:
+	}
+}
+
+func TestPageEventStreamConnectionFailureCanRetry(t *testing.T) {
+	server := httptest.NewServer(http.NotFoundHandler())
+	server.Close()
+	p := &page{client: NewClient(wv.RPCConfig{Network: "tcp", Address: strings.TrimPrefix(server.URL, "http://")}), id: "offline-page"}
+	for i := 0; i < 2; i++ {
+		if off, err := p.On("load", func(wv.Event) {}); err == nil || off != nil {
+			t.Fatal("registration to unavailable host succeeded")
+		}
+	}
+	if p.eventCancel != nil {
+		t.Fatal("failed connection retained an active stream")
+	}
+}