feat(app): add internal components batch 1

internal/app/diagnostics_test.go

@@ -0,0 +1,137 @@
+package app
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+)
+
+func readDiagnosticEvents(t *testing.T, path string) []diagnosticEvent {
+	t.Helper()
+	file, err := os.Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer file.Close()
+	var events []diagnosticEvent
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		var event diagnosticEvent
+		if err := json.Unmarshal(scanner.Bytes(), &event); err != nil || event.Time.IsZero() || event.Event == "" {
+			t.Fatal("invalid diagnostic record", err)
+		}
+		events = append(events, event)
+	}
+	if err := scanner.Err(); err != nil {
+		t.Fatal(err)
+	}
+	return events
+}
+
+func TestDiagnosticLogConcurrentWritesAndRedaction(t *testing.T) {
+	log := newDiagnosticLog(t.TempDir())
+	d := &Downloader{diagnostics: log}
+	var group sync.WaitGroup
+	for index := 0; index < 50; index++ {
+		group.Add(1)
+		go func(index int) {
+			defer group.Done()
+			d.recordDiagnostic(diagnosticEvent{Event: "fixture.failed", Episode: index + 1, Message: "https://user:fixture-password@media.invalid/video?token=fixture-token&key=fixture-media-key&signature=fixture-signature#fixture-fragment"})
+		}(index)
+	}
+	group.Wait()
+	events := readDiagnosticEvents(t, log.path)
+	seen := make(map[int]bool)
+	for _, event := range events {
+		seen[event.Episode] = true
+		for _, secret := range []string{"fixture-token", "fixture-media-key", "fixture-password", "fixture-signature", "fixture-fragment"} {
+			if strings.Contains(event.Message, secret) {
+				t.Fatal("diagnostic log exposed a credential or signed URL parameter")
+			}
+		}
+	}
+	if len(events) != 50 || len(seen) != 50 {
+		t.Fatal("concurrent diagnostic events were lost or interleaved")
+	}
+	info, err := os.Stat(log.path)
+	if err != nil || runtime.GOOS != "windows" && info.Mode().Perm()&0077 != 0 {
+		t.Fatal("new diagnostic file was not private", err)
+	}
+}
+
+func TestDiagnosticLogRotationBoundsFiles(t *testing.T) {
+	log := newDiagnosticLog(t.TempDir())
+	log.limit = 512
+	for index := 0; index < 30; index++ {
+		if err := log.write(diagnosticEvent{Event: "fixture.rotate", Episode: index, Message: strings.Repeat("x", 100)}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	files, err := os.ReadDir(filepath.Dir(log.path))
+	if err != nil || len(files) != diagnosticLogBackups+1 {
+		t.Fatal("diagnostic rotation exceeded its file bound", err)
+	}
+	for _, file := range files {
+		info, err := file.Info()
+		if err != nil || info.Size() > log.limit || len(readDiagnosticEvents(t, filepath.Join(filepath.Dir(log.path), file.Name()))) == 0 {
+			t.Fatal("rotation kept an oversized or invalid file", err)
+		}
+	}
+	current := readDiagnosticEvents(t, log.path)
+	if current[len(current)-1].Episode != 29 {
+		t.Fatal("rotation discarded the latest event")
+	}
+	if err := newDiagnosticLog(filepath.Dir(filepath.Dir(log.path))).write(diagnosticEvent{Event: "fixture.restart", Message: "restart"}); err != nil {
+		t.Fatal("reopening diagnostics failed", err)
+	}
+}
+
+func TestDiagnosticWriteFailureDoesNotReplacePlaybackError(t *testing.T) {
+	directory := t.TempDir()
+	if err := os.WriteFile(filepath.Join(directory, "logs"), []byte("keep"), 0600); err != nil {
+		t.Fatal(err)
+	}
+	log := newDiagnosticLog(directory)
+	if err := log.write(diagnosticEvent{Event: "fixture.failed", Message: "failure"}); err == nil {
+		t.Fatal("unwritable diagnostics unexpectedly succeeded")
+	}
+	d := &Downloader{diagnostics: log}
+	d.recordTaskFailure("playback.failed", Task{}, 49, errors.New("unexpected EOF"))
+	data, err := os.ReadFile(filepath.Join(directory, "logs"))
+	if err != nil || string(data) != "keep" {
+		t.Fatal("diagnostics replaced an existing file", err)
+	}
+}
+
+func TestPlaybackFailureLogIncludesEpisodeAndSkipsStoppedRun(t *testing.T) {
+	app, session := prefetchFixtureApp(t)
+	session.tasks[0] = Task{DramaID: "hongguo:7000000000000000001", DramaTitle: "合成播放条目", Index: 1}
+	run, _, err := app.beginPlayback(viewerFixtureContext(app, context.Background()), "fixture", 1, 49, 0, 1, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer run.stop()
+	app.finishPlaybackRun(run, errors.New("unexpected EOF"), false)
+	app.finishPlaybackRun(run, context.Canceled, true)
+	events := readDiagnosticEvents(t, app.downloader.diagnostics.path)
+	failures := 0
+	for _, event := range events {
+		if event.Event == "playback.failed" {
+			failures++
+			if event.DramaID != run.task.DramaID || event.DramaTitle != run.task.DramaTitle || event.Episode != 1 || event.StartSeconds != 49 || event.Message != "unexpected EOF" {
+				t.Fatal("playback failure lost its diagnostic context", fmt.Sprint(event))
+			}
+		}
+	}
+	if failures != 1 {
+		t.Fatal("stopping playback generated a false diagnostic failure")
+	}
+}