Allow selecting individual files to torrent

Saves bandwidth and disk space when a torrent contains extra files you don't need

Fixes #360

renderer/index.css

@@ -113,6 +113,10 @@ table {
   opacity: 0.3;
 }
 
+.clickable {
+  cursor: pointer;
+}
+
 .float-right {
   float: right;
 }
@@ -597,7 +601,7 @@ body.drag .app::after {
 }
 
 .torrent-details {
-  padding: 8em 20px 20px 20px;
+  padding: 8em 12px 20px 20px;
 }
 
 .torrent-details table {
@@ -611,6 +615,10 @@ body.drag .app::after {
   height: 28px;
 }
 
+.torrent-details td {
+  vertical-align: center;
+}
+
 .torrent-details tr:hover {
   background-color: rgba(200, 200, 200, 0.3);
 }
@@ -621,16 +629,16 @@ body.drag .app::after {
   vertical-align: bottom;
 }
 
-.torrent-details td.col-icon {
-  width: 2em;
-}
-
-.torrent-details td.col-icon .icon {
+.torrent-details td .icon {
   font-size: 18px;
   position: relative;
   top: 3px;
 }
 
+.torrent-details td.col-icon {
+  width: 2em;
+}
+
 .torrent-details td.col-name {
   width: auto;
   text-overflow: ellipsis;
@@ -646,6 +654,11 @@ body.drag .app::after {
   text-align: right;
 }
 
+.torrent-details td.col-select {
+  width: 2em;
+  text-align: right;
+}
+
 /*
  * PLAYER
  */

renderer/index.js

@@ -153,6 +153,11 @@ function cleanUpConfig () {
       delete ts.posterURL
       ts.posterFileName = infoHash + extension
     }
+
+    // Migration: add per-file selections
+    if (!ts.selections) {
+      ts.selections = ts.files.map((x) => true)
+    }
   })
 }
 
@@ -231,6 +236,9 @@ function dispatch (action, ...args) {
   if (action === 'toggleSelectTorrent') {
     toggleSelectTorrent(args[0] /* infoHash */)
   }
+  if (action === 'toggleTorrentFile') {
+    toggleTorrentFile(args[0] /* infoHash */, args[1] /* index */)
+  }
   if (action === 'openTorrentContextMenu') {
     openTorrentContextMenu(args[0] /* infoHash */)
   }
@@ -709,7 +717,7 @@ function startTorrentingSummary (torrentSummary) {
   }
 
   console.log('start torrenting %s %s', s.torrentKey, torrentID)
-  ipcRenderer.send('wt-start-torrenting', s.torrentKey, torrentID, path, s.fileModtimes)
+  ipcRenderer.send('wt-start-torrenting', s.torrentKey, torrentID, path, s.fileModtimes, s.selections)
 }
 
 //
@@ -818,6 +826,9 @@ function torrentMetadata (torrentKey, torrentInfo) {
   torrentSummary.path = torrentInfo.path
   torrentSummary.files = torrentInfo.files
   torrentSummary.magnetURI = torrentInfo.magnetURI
+  if (!torrentSummary.selections) {
+    torrentSummary.selections = torrentSummary.files.map((x) => true)
+  }
   update()
 
   // Save the .torrent file, if it hasn't been saved already
@@ -1058,6 +1069,14 @@ function toggleSelectTorrent (infoHash) {
   update()
 }
 
+function toggleTorrentFile (infoHash, index) {
+  var torrentSummary = getTorrentSummary(infoHash)
+  torrentSummary.selections[index] = !torrentSummary.selections[index]
+
+  // Let the WebTorrent process know to start or stop fetching that file
+  ipcRenderer.send('wt-select-files', infoHash, torrentSummary.selections)
+}
+
 function openTorrentContextMenu (infoHash) {
   var torrentSummary = getTorrentSummary(infoHash)
   var menu = new electron.remote.Menu()

renderer/views/torrent-list.js

@@ -208,7 +208,8 @@ function TorrentList (state) {
   // Show a single torrentSummary file in the details view for a single torrent
   function renderFileRow (torrentSummary, file, index) {
     // First, find out how much of the file we've downloaded
-    var isDone = false
+    var isSelected = torrentSummary.selections[index] // Are we even torrenting it?
+    var isDone = false // Are we finished torrenting it?
     var progress = ''
     if (torrentSummary.progress && torrentSummary.progress.files) {
       var fileProg = torrentSummary.progress.files[index]
@@ -217,26 +218,38 @@ function TorrentList (state) {
     }
 
     // Second, render the file as a table row
+    var isPlayable = TorrentPlayer.isPlayable(file)
     var infoHash = torrentSummary.infoHash
     var icon
-    var rowClass = ''
     var handleClick
-    if (TorrentPlayer.isPlayable(file)) {
+    if (isPlayable) {
       icon = 'play_arrow' /* playable? add option to play */
       handleClick = dispatcher('play', infoHash, index)
     } else {
       icon = 'description' /* file icon, opens in OS default app */
-      rowClass = isDone ? '' : 'disabled'
       handleClick = dispatcher('openFile', infoHash, index)
     }
+    var rowClass = 'clickable'
+    if (!isSelected) rowClass = 'disabled' // File deselected, not being torrented
+    if (!isDone && !isPlayable) rowClass = 'disabled' // Can't open yet, can't stream
     return hx`
-      <tr onclick=${handleClick} class='${rowClass}'>
-        <td class='col-icon'>
+      <tr>
+        <td class='col-icon ${rowClass}' onclick=${handleClick}>
           <i class='icon'>${icon}</i>
         </td>
-        <td class='col-name'>${file.name}</td>
-        <td class='col-progress'>${progress}</td>
-        <td class='col-size'>${prettyBytes(file.length)}</td>
+        <td class='col-name ${rowClass}' onclick=${handleClick}>
+          ${file.name}
+        </td>
+        <td class='col-progress ${rowClass}' onclick=${handleClick}>
+          ${isSelected ? progress : ''}
+        </td>
+        <td class='col-size ${rowClass}' onclick=${handleClick}>
+          ${prettyBytes(file.length)}
+        </td>
+        <td class='col-select'
+            onclick=${dispatcher('toggleTorrentFile', infoHash, index)}>
+          <i class='icon'>${isSelected ? 'close' : 'add'}</i>
+        </td>
       </tr>
     `
   }

renderer/webtorrent.js

@@ -49,8 +49,8 @@ function init () {
   client.on('warning', (err) => ipc.send('wt-warning', null, err.message))
   client.on('error', (err) => ipc.send('wt-error', null, err.message))
 
-  ipc.on('wt-start-torrenting', (e, torrentKey, torrentID, path, fileModtimes) =>
-    startTorrenting(torrentKey, torrentID, path, fileModtimes))
+  ipc.on('wt-start-torrenting', (e, torrentKey, torrentID, path, fileModtimes, selections) =>
+    startTorrenting(torrentKey, torrentID, path, fileModtimes, selections))
   ipc.on('wt-stop-torrenting', (e, infoHash) =>
     stopTorrenting(infoHash))
   ipc.on('wt-create-torrent', (e, torrentKey, options) =>
@@ -65,6 +65,8 @@ function init () {
     startServer(infoHash, index))
   ipc.on('wt-stop-server', (e) =>
     stopServer())
+  ipc.on('wt-select-files', (e, infoHash, selections) =>
+    selectFiles(infoHash, selections))
 
   ipc.send('ipcReadyWebTorrent')
 
@@ -73,7 +75,7 @@ function init () {
 
 // Starts a given TorrentID, which can be an infohash, magnet URI, etc. Returns WebTorrent object
 // See https://github.com/feross/webtorrent/blob/master/docs/api.md#clientaddtorrentid-opts-function-ontorrent-torrent-
-function startTorrenting (torrentKey, torrentID, path, fileModtimes) {
+function startTorrenting (torrentKey, torrentID, path, fileModtimes, selections) {
   console.log('starting torrent %s: %s', torrentKey, torrentID)
 
   var torrent = client.add(torrentID, {
@@ -81,8 +83,13 @@ function startTorrenting (torrentKey, torrentID, path, fileModtimes) {
     fileModtimes: fileModtimes
   })
   torrent.key = torrentKey
+
+  // Listen for ready event, progress notifications, etc
   addTorrentEvents(torrent)
 
+  // Only download the files the user wants, not necessarily all files
+  torrent.once('ready', () => selectFiles(torrent, selections))
+
   return torrent
 }
 
@@ -308,6 +315,48 @@ function getAudioMetadata (infoHash, index) {
   })
 }
 
+function selectFiles (torrentOrInfoHash, selections) {
+  // Get the torrent object
+  var torrent
+  if (typeof torrentOrInfoHash === 'string') {
+    torrent = client.get(torrentOrInfoHash)
+  } else {
+    torrent = torrentOrInfoHash
+  }
+
+  // Selections not specified?
+  // Load all files. We still need to replace the default whole-torrent
+  // selection with individual selections for each file, so we can
+  // select/deselect files later on
+  if (!selections) {
+    selections = torrent.files.map((x) => true)
+  }
+
+  // Selections specified incorrectly?
+  if (selections.length !== torrent.files.length) {
+    throw new Error('got ' + selections.length + ' file selections, ' +
+      'but the torrent contains ' + torrent.files.length + ' files')
+  }
+
+  // Remove default selection (whole torrent)
+  torrent.deselect(0, torrent.pieces.length - 1, false)
+
+  // Add selections (individual files)
+  for (var i = 0; i < selections.length; i++) {
+    var file = torrent.files[i]
+    if (selections[i]) {
+      file.select()
+    } else {
+      console.log('deselecting file ' + i + ' of torrent ' + torrent.name)
+      file.deselect()
+
+      // If we deselected a file, try to nuke it to save disk space
+      var filePath = path.join(torrent.path, file.path)
+      fs.unlink(filePath) // Ignore errors for now
+    }
+  }
+}
+
 // Gets a WebTorrent handle by torrentKey
 // Throws an Error if we're not currently torrenting anything w/ that key
 function getTorrent (torrentKey) {