Control downloads and show history in the web interface

README.md

@@ -87,9 +87,9 @@ for container hostnames, volume mounts and Remote Path Mappings.
 
 ## Web interface
 
-Open `http://<magnetowid-host>:8484/` and sign in with the API key to watch the
-download queue: the current download's progress, what's next, and any retries.
-See [Web interface](docs/usage.md#web-interface).
+Open `http://<magnetowid-host>:8484/` and sign in with the API key to see the
+queue and history, and to pause, resume or remove downloads. See
+[Web interface](docs/usage.md#web-interface).
 
 ## Help and contributing
 

docs/usage.md

@@ -148,8 +148,9 @@ default). Subtitle failures log a warning and keep the video.
 
 ### Pausing downloads
 
-Use SABnzbd API commands to pause or resume the queue or individual jobs.
-Sonarr and Radarr display paused jobs but cannot control pausing:
+Pause or resume the queue or single jobs in the [web interface](#web-interface)
+or with SABnzbd API commands. Sonarr and Radarr show paused jobs but cannot
+pause them:
 
 ```sh
 curl 'http://localhost:8484/api?mode=pause&apikey=YOUR_API_KEY'
@@ -163,13 +164,21 @@ interrupted downloads restart from the beginning when resumed.
 
 ## Web interface
 
-Open `http://<host>:8484/` in a browser and sign in with the API key. The page
-shows the running download's progress and time left, the queued jobs in the
-order they will run, and paused or retrying jobs with their last error. It
-refreshes itself every second.
+Open `http://<host>:8484/` in a browser and sign in with the API key.
+
+**Queue** shows the running download's progress and time left, queued jobs in
+run order, and paused or retrying jobs with their last error. It refreshes
+every second. Pause or resume the queue or a job, or remove a job; removing the
+running download deletes its partial file. Resumed downloads restart from the
+beginning.
+
+**History** lists finished and failed downloads, newest first, and refreshes
+every five seconds. Downloads stay for 30 days unless Sonarr or Radarr removes
+them first. Removing one can also delete its folder; Sonarr and Radarr cannot
+import a download removed from history.
 
 Signing in lasts 30 days. Changing `MAGNETOWID_API_KEY` signs every browser
-out. Search for titles and manage downloads in Sonarr/Radarr.
+out. Search for titles in Sonarr/Radarr.
 
 ## Correcting matches
 
@@ -252,8 +261,8 @@ under **Settings → Download Clients**:
 
 ## Troubleshooting
 
-Search for titles and manage downloads in Sonarr/Radarr. The
-[web interface](#web-interface) shows magnetowid's download queue.
+Search for titles in Sonarr/Radarr. The [web interface](#web-interface) shows
+the queue and history, with the last error of each failed or retrying job.
 
 | Problem | What to check |
 |---|---|

internal/downloader/queue.go

@@ -102,7 +102,8 @@ func (j Job) TimeLeft(now time.Time) time.Duration {
 	return time.Duration(float64(now.Sub(j.Started)) * (1 - j.Fraction) / j.Fraction)
 }
 
-const historyRetention = 30 * 24 * time.Hour
+// HistoryRetention is how long finished jobs are kept.
+const HistoryRetention = 30 * 24 * time.Hour
 
 const incompleteDir = ".incomplete"
 
@@ -308,9 +309,19 @@ func (q *Queue) Jobs() []Job {
 // Delete cancels the job and optionally removes its files. It returns false for
 // unknown IDs; a save failure leaves the job unchanged.
 func (q *Queue) Delete(id string, deleteFiles bool) (bool, error) {
+	return q.discard(id, deleteFiles, false)
+}
+
+// Cancel deletes an unfinished job. It returns false for unknown and finished
+// jobs, which stay in history for import.
+func (q *Queue) Cancel(id string) (bool, error) {
+	return q.discard(id, false, true)
+}
+
+func (q *Queue) discard(id string, deleteFiles, unfinishedOnly bool) (bool, error) {
 	q.mu.Lock()
 	job, ok := q.jobs[id]
-	if !ok {
+	if !ok || (unfinishedOnly && job.Status != StatusQueued && job.Status != StatusDownloading) {
 		q.mu.Unlock()
 		return false, nil
 	}
@@ -506,7 +517,7 @@ func (q *Queue) prune(now time.Time) {
 	var old []string
 	for _, id := range q.order {
 		j := q.jobs[id]
-		if (j.Status == StatusCompleted || j.Status == StatusFailed) && now.Sub(j.Finished) > historyRetention {
+		if (j.Status == StatusCompleted || j.Status == StatusFailed) && now.Sub(j.Finished) > HistoryRetention {
 			old = append(old, id)
 		}
 	}

internal/downloader/queue_test.go

@@ -425,6 +425,36 @@ func TestPauseRunningJob(t *testing.T) {
 	waitJob(t, q, id, func(j Job) bool { return j.Status == StatusDownloading && !j.Paused && j.Attempts == 1 })
 }
 
+func TestCancel(t *testing.T) {
+	e := &blockingEngine{started: make(chan string, 2)}
+	q := newQueue(t, t.TempDir(), &fakeProvider{}, e)
+	run(t, q)
+	running := add(t, q, "a", "tv", 0, nzb.Ref{Provider: "fake", ID: "a"})
+	<-e.started
+	queued := add(t, q, "b", "tv", 0, nzb.Ref{Provider: "fake", ID: "b"})
+	for _, id := range []string{queued, running} {
+		if ok, err := q.Cancel(id); !ok || err != nil {
+			t.Fatalf("Cancel(%s) = %v, %v", id, ok, err)
+		}
+	}
+	if jobs := q.Jobs(); len(jobs) != 0 {
+		t.Errorf("jobs after cancelling = %+v", jobs)
+	}
+	if ok, err := q.Cancel("SABnzbd_nzo_gone"); ok || err != nil {
+		t.Errorf("cancelling an unknown job = %v, %v", ok, err)
+	}
+
+	// A finished job stays for import.
+	q = startQueue(t, &fakeProvider{}, &fakeEngine{})
+	done := waitFinished(t, q, add(t, q, "c", "tv", 0, nzb.Ref{Provider: "fake", ID: "c"}))
+	if ok, err := q.Cancel(done.ID); ok || err != nil {
+		t.Errorf("cancelling a finished job = %v, %v", ok, err)
+	}
+	if _, err := os.Stat(done.Storage); len(q.Jobs()) != 1 || err != nil {
+		t.Errorf("finished job after a cancel: %+v, files %v", q.Jobs(), err)
+	}
+}
+
 func TestPauseBeforeDownloadStarts(t *testing.T) {
 	for name, pause := range map[string]func(q *Queue, id string) error{
 		"job":   func(q *Queue, id string) error { _, err := q.PauseJobs(id); return err },
@@ -586,7 +616,7 @@ func TestPruneOldHistory(t *testing.T) {
 	dir := t.TempDir()
 	q := newQueue(t, dir, &fakeProvider{}, &fakeEngine{})
 	now := time.Now()
-	old := now.Add(-historyRetention - time.Hour)
+	old := now.Add(-HistoryRetention - time.Hour)
 	set := func(name string, status Status, finished time.Time) string {
 		id := add(t, q, name, "tv", 0, nzb.Ref{Provider: "fake", ID: name})
 		q.mu.Lock()