erste module drin.

zwischenstand: Architektur aktualisiert, TOFU implementiert,

pkg/stream/decoder_test.go

@@ -0,0 +1,110 @@
+package stream
+
+import (
+	"encoding/json"
+	"errors"
+	"io"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+const evJSON = `{"event_id":"evt_1","timestamp":1,"type":"node_command","node_id":"n1","payload":{"action":"drain"}}`
+
+var evWant = Event{
+	ID:        "evt_1",
+	Timestamp: 1,
+	Type:      EventNodeCommand,
+	NodeID:    "n1",
+	Payload:   json.RawMessage(`{"action":"drain"}`),
+}
+
+func decodeAll(t *testing.T, input string) ([]Event, error) {
+	t.Helper()
+	dec := NewDecoder(strings.NewReader(input))
+	var out []Event
+	for {
+		ev, err := dec.Next()
+		if err != nil {
+			return out, err
+		}
+		out = append(out, ev)
+	}
+}
+
+func TestDecoder(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  []Event
+	}{
+		{"einzelnes Event", "id: evt_1\nevent: node_command\ndata: " + evJSON + "\n\n", []Event{evWant}},
+		{"Keepalives werden übersprungen", ":\n\n:\n\ndata: " + evJSON + "\n\n:\n\n", []Event{evWant}},
+		{"CRLF-Zeilenenden", "id: evt_1\r\ndata: " + evJSON + "\r\n\r\n", []Event{evWant}},
+		{"data ohne Leerzeichen", "data:" + evJSON + "\n\n", []Event{evWant}},
+		{
+			"mehrere data-Zeilen",
+			"data: {\"event_id\":\"evt_1\",\"timestamp\":1,\ndata: \"type\":\"node_command\",\"node_id\":\"n1\",\ndata: \"payload\":{\"action\":\"drain\"}}\n\n",
+			[]Event{evWant},
+		},
+		{"unbekannte Felder ignoriert", "retry: 1000\nfoo: bar\ndata: " + evJSON + "\n\n", []Event{evWant}},
+		{"Leerzeilen ohne Daten", "\n\n\nevent: x\n\n", nil},
+		{"zwei Events", "data: " + evJSON + "\n\ndata: " + evJSON + "\n\n", []Event{evWant, evWant}},
+		{"leerer Stream", "", nil},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := decodeAll(t, tt.input)
+			if !errors.Is(err, io.EOF) {
+				t.Fatalf("erwartet io.EOF am Ende, bekommen %v", err)
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("Events weichen ab\n got: %+v\nwant: %+v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestDecoder_Errors(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  error
+	}{
+		{"ungültiges JSON", "data: {kaputt\n\n", ErrInvalidEvent},
+		{"Event ohne Typ", "data: {\"event_id\":\"evt_1\"}\n\n", ErrInvalidEvent},
+		{"abgeschnittenes Event", "data: " + evJSON + "\n", io.ErrUnexpectedEOF},
+		{"Zeile zu lang", "data: " + strings.Repeat("x", MaxEventSize+1) + "\n\n", ErrEventTooLarge},
+		{"Summe der data-Zeilen zu lang", strings.Repeat("data: "+strings.Repeat("x", MaxEventSize/4)+"\n", 5) + "\n", ErrEventTooLarge},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := decodeAll(t, tt.input)
+			if !errors.Is(err, tt.want) {
+				t.Errorf("erwartet %v, bekommen %v", tt.want, err)
+			}
+		})
+	}
+}
+
+func TestEncodeDecodeRoundTrip(t *testing.T) {
+	ev, err := NewEvent(EventServiceState, map[string]any{"labels": map[string]string{"traefik.enable": "true"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	ev.NodeID = "n1"
+	frame, err := encode(ev)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.HasPrefix(string(frame), "id: "+ev.ID+"\nevent: service_state\ndata: ") || !strings.HasSuffix(string(frame), "\n\n") {
+		t.Errorf("unerwarteter SSE-Rahmen: %q", frame)
+	}
+	got, err := NewDecoder(strings.NewReader(string(frame))).Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(got, ev) {
+		t.Errorf("Round-Trip weicht ab\n got: %+v\nwant: %+v", got, ev)
+	}
+}