feat: add speed limit to client (#2062)

* Add speed limit to client

* Fix standard

* Update docs/api.md

* Add changes from PR feedback

Co-authored-by: Kadu Diógenes <kadu@fnix.com.br>
Co-authored-by: Ivan Gorbanev <ivang@van.work>
Co-authored-by: ultimate-tester <jordimueters@hotmail.com>
Co-authored-by: Julen Garcia Leunda <hicom150@gmail.com>
Co-authored-by: Niklas Johansson <niklas.y.johansson@se.abb.com>
Co-authored-by: ThaUnknown <kapi.skowronek@gmail.com>
Co-authored-by: Diego Rodríguez Baquero <github@diegorbaquero.com>

2 files changed, 170 insertions, 0 deletions

diff --git a/test/node/limit-download-upload.js b/test/node/limit-download-upload.js
new file mode 100644
index 0000000..0f595ba
--- /dev/null
+++ b/test/node/limit-download-upload.js
@@ -0,0 +1,82 @@
+const fixtures = require('webtorrent-fixtures')
+const test = require('tape')
+const WebTorrent = require('../../')
+const MemoryChunkStore = require('memory-chunk-store')
+
+const DOWNLOAD_SPEED_LIMIT = 200 * 1000 // 200 KB/s
+const UPLOAD_SPEED_LIMIT = 200 * 1000 // 200 KB/s
+
+function testSpeed (t, downloaderOpts, uploaderOpts, cb) {
+  const client1 = new WebTorrent({ dht: false, tracker: false, ...downloaderOpts })
+  const client2 = new WebTorrent({ dht: false, tracker: false, ...uploaderOpts })
+
+  client1.on('error', err => { t.fail(err) })
+  client1.on('warning', err => { t.fail(err) })
+
+  client2.on('error', err => { t.fail(err) })
+  client2.on('warning', err => { t.fail(err) })
+
+  const downloadSpeeds = []
+  const uploadSpeeds = []
+
+  // Start seeding
+  client2.seed(fixtures.leaves.content, {
+    name: 'Leaves of Grass by Walt Whitman.epub',
+    announce: []
+  }, torrent => {
+    torrent.on('upload', () => {
+      uploadSpeeds.push(torrent.uploadSpeed)
+    })
+  })
+
+  client2.on('listening', () => {
+    // Start downloading
+    const torrent = client1.add(fixtures.leaves.parsedTorrent.infoHash, { store: MemoryChunkStore })
+
+    // Manually connect peers
+    torrent.addPeer(`127.0.0.1:${client2.address().port}`)
+
+    torrent.on('download', () => {
+      downloadSpeeds.push(torrent.downloadSpeed)
+    })
+
+    torrent.on('done', () => {
+      cb(downloadSpeeds, uploadSpeeds)
+
+      client1.destroy(err => { t.error(err, 'client 1 destroyed') })
+      client2.destroy(err => { t.error(err, 'client 2 destroyed') })
+    })
+  })
+}
+
+test('Limit download speed by constructor when tcp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { downloadLimit: DOWNLOAD_SPEED_LIMIT }, {}, downloadSpeeds => {
+    t.ok(downloadSpeeds.every(downloadSpeed => downloadSpeed <= DOWNLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit upload speed by constructor when tcp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, {}, { uploadLimit: UPLOAD_SPEED_LIMIT }, (_, uploadSpeeds) => {
+    t.ok(uploadSpeeds.every(uploadSpeed => uploadSpeed <= UPLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit download speed by constructor when utp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { utp: true, downloadLimit: DOWNLOAD_SPEED_LIMIT }, { utp: true }, downloadSpeeds => {
+    t.ok(downloadSpeeds.every(downloadSpeed => downloadSpeed <= DOWNLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit upload speed by constructor when utp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { utp: true }, { utp: true, uploadLimit: UPLOAD_SPEED_LIMIT }, (_, uploadSpeeds) => {
+    t.ok(uploadSpeeds.every(uploadSpeed => uploadSpeed <= UPLOAD_SPEED_LIMIT))
+  })
+})
diff --git a/test/node/limit-methods.js b/test/node/limit-methods.js
new file mode 100644
index 0000000..58ad573
--- /dev/null
+++ b/test/node/limit-methods.js
@@ -0,0 +1,88 @@
+const fixtures = require('webtorrent-fixtures')
+const test = require('tape')
+const WebTorrent = require('../../')
+const MemoryChunkStore = require('memory-chunk-store')
+
+const DOWNLOAD_SPEED_LIMIT = 200 * 1000 // 200 KB/s
+const UPLOAD_SPEED_LIMIT = 200 * 1000 // 200 KB/s
+
+function testSpeed (t, downloaderOpts, uploaderOpts, cb) {
+  const { downloadLimit, ...restDownloaderOpts } = downloaderOpts
+  const { uploadLimit, ...restUploaderOpts } = uploaderOpts
+
+  const client1 = new WebTorrent({ dht: false, tracker: false, ...restDownloaderOpts })
+  const client2 = new WebTorrent({ dht: false, tracker: false, ...restUploaderOpts })
+
+  if (downloadLimit) client1.throttleDownload(downloadLimit)
+  if (uploadLimit) client2.throttleUpload(uploadLimit)
+
+  client1.on('error', err => { t.fail(err) })
+  client1.on('warning', err => { t.fail(err) })
+
+  client2.on('error', err => { t.fail(err) })
+  client2.on('warning', err => { t.fail(err) })
+
+  const downloadSpeeds = []
+  const uploadSpeeds = []
+
+  // Start seeding
+  client2.seed(fixtures.leaves.content, {
+    name: 'Leaves of Grass by Walt Whitman.epub',
+    announce: []
+  }, torrent => {
+    torrent.on('upload', () => {
+      uploadSpeeds.push(torrent.uploadSpeed)
+    })
+  })
+
+  client2.on('listening', () => {
+    // Start downloading
+    const torrent = client1.add(fixtures.leaves.parsedTorrent.infoHash, { store: MemoryChunkStore })
+
+    // Manually connect peers
+    torrent.addPeer(`127.0.0.1:${client2.address().port}`)
+
+    torrent.on('download', () => {
+      downloadSpeeds.push(torrent.downloadSpeed)
+    })
+
+    torrent.on('done', () => {
+      cb(downloadSpeeds, uploadSpeeds)
+
+      client1.destroy(err => { t.error(err, 'client 1 destroyed') })
+      client2.destroy(err => { t.error(err, 'client 2 destroyed') })
+    })
+  })
+}
+
+test('Limit download speed by methods when tcp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { downloadLimit: DOWNLOAD_SPEED_LIMIT }, {}, downloadSpeeds => {
+    t.ok(downloadSpeeds.every(downloadSpeed => downloadSpeed <= DOWNLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit upload speed by methods when tcp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, {}, { uploadLimit: UPLOAD_SPEED_LIMIT }, (_, uploadSpeeds) => {
+    t.ok(uploadSpeeds.every(uploadSpeed => uploadSpeed <= UPLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit download speed by methods when utp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { utp: true, downloadLimit: DOWNLOAD_SPEED_LIMIT }, { utp: true }, downloadSpeeds => {
+    t.ok(downloadSpeeds.every(downloadSpeed => downloadSpeed <= DOWNLOAD_SPEED_LIMIT))
+  })
+})
+
+test('Limit upload speed by methods when utp connection', t => {
+  t.plan(3)
+
+  testSpeed(t, { utp: true }, { utp: true, uploadLimit: UPLOAD_SPEED_LIMIT }, (_, uploadSpeeds) => {
+    t.ok(uploadSpeeds.every(uploadSpeed => uploadSpeed <= UPLOAD_SPEED_LIMIT))
+  })
+})