add pause/resume and improve network join/leave (#121)

* add pause/resume and improve network join/leave

* add docs

* remove db close

* use leave for network close

* cleanup snapshot test

* add console to figure out why test fail

* check closed on pause test

* use download finished for pause test

Author: Joe Hand

dat.js

@@ -59,11 +59,12 @@ Dat.prototype.joinNetwork = function (opts, cb) {
     cb = opts
     opts = {}
   }
-  opts = opts || {}
-  cb = cb || noop
-  if (this.network) return this.network.join(this.archive.discoveryKey, { announce: opts.upload }, cb)
 
   var self = this
+  if (!opts && self.options.network) opts = self.options.network // use previous options
+  else opts = opts || {}
+  cb = cb || noop
+
   var netOpts = xtend({
     stream: function (peer) {
       var stream = self.archive.replicate({
@@ -78,7 +79,7 @@ Dat.prototype.joinNetwork = function (opts, cb) {
   }, opts)
 
   var network = self.network = createNetwork(self.archive, netOpts, cb)
-  self.options.network = network.options
+  self.options.network = netOpts
   network.swarm = network // 1.0 backwards compat. TODO: Remove in v2
 
   if (self.owner) return network
@@ -91,9 +92,23 @@ Dat.prototype.joinNetwork = function (opts, cb) {
 }
 
 Dat.prototype.leave =
-Dat.prototype.leaveNetwork = function () {
+Dat.prototype.leaveNetwork = function (cb) {
   if (!this.network) return
+  debug('leaveNetwork()')
+  this.archive.unreplicate()
   this.network.leave(this.archive.discoveryKey)
+  this.network.destroy(cb)
+  delete this.network
+}
+
+Dat.prototype.pause = function () {
+  debug('pause()')
+  this.leave()
+}
+
+Dat.prototype.resume = function () {
+  debug('resume()')
+  this.join()
 }
 
 Dat.prototype.trackStats = function (opts) {
@@ -132,10 +147,7 @@ Dat.prototype.close = function (cb) {
   closeFileWatch(done())
   closeArchiveDb(done())
 
-  done(function (err) {
-    if (err) return cb(err)
-    cb()
-  })
+  done(cb)
 
   function closeArchiveDb (cb) {
     self.archive.close(function (err) {
@@ -152,7 +164,7 @@ Dat.prototype.close = function (cb) {
 
   function closeNet (cb) {
     if (!self.network) return cb()
-    self.network.close(cb)
+    self.leave(cb)
   }
 
   function closeFileWatch (cb) {

readme.md

@@ -255,6 +255,14 @@ Additionally, you can use a `.datignore` file to ignore any the user specifies.
 
 Get upload and download speeds: `stats.network.uploadSpeed` or `stats.network.downloadSpeed`. Transfer speeds are tracked using [hyperdrive-network-speed](https://github.com/joehand/hyperdrive-network-speed/).
 
+#### `dat.pause()`
+
+Pause all upload & downloads. Currently, this is the same as `dat.leaveNetwork()`, which leaves the network and destroys the swarm. Discovery will happen again on `resume()`.
+
+#### `dat.resume()`
+
+Resume network activity. Current, this is the same as `dat.joinNetwork()`.
+
 #### `dat.close(cb)`
 
 Stops replication and closes all the things opened for dat-node, including:

test/download.js

@@ -4,6 +4,7 @@ var os = require('os')
 var test = require('tape')
 var rimraf = require('rimraf')
 var mkdirp = require('mkdirp')
+var memdb = require('memdb')
 
 var Dat = require('..')
 
@@ -26,7 +27,7 @@ test('prep', function (t) {
     t.error(err, 'share error okay')
     shareKey = dat.key
     shareDat = dat
-    dat.joinNetwork()
+    dat.joinNetwork({ dht: false })
     dat.importFiles({ live: true }, function () { // need live for live download tests!
       testFolder(function () {
         t.end()
@@ -185,7 +186,46 @@ test('Download with sparse', function (t) {
   })
 })
 
-test('close first sharer', function (t) {
+test('Download pause', function (t) {
+  testFolder(function () {
+    Dat(downloadDir, {key: shareKey, db: memdb()}, function (err, dat) {
+      t.error(err, 'no download init error')
+
+      var paused = false
+      dat.joinNetwork({ dht: false }).once('connection', function () {
+        dat.pause()
+        paused = true
+
+        dat.archive.on('download', failDownload)
+
+        setTimeout(function () {
+          dat.archive.removeListener('download', failDownload)
+          dat.resume()
+          paused = false
+        }, 500)
+
+        function failDownload () {
+          if (paused) t.fail('download when paused')
+        }
+      })
+
+      dat.archive.open(function () {
+        dat.archive.content.on('download-finished', done)
+      })
+
+      function done () {
+        t.pass('finished download after resume')
+        if (dat._closed) return
+        dat.close(function (err) {
+          t.error(err, 'no error')
+          t.end()
+        })
+      }
+    })
+  })
+})
+
+test('close first test', function (t) {
   shareDat.close(function (err) {
     t.error(err, 'no close error')
     t.pass('close')
@@ -196,12 +236,13 @@ test('close first sharer', function (t) {
 
 test('download joinNetwork callback without connections', function (t) {
   testFolder(function () {
-    Dat(downloadDir, function (err, dat) {
+    Dat(downloadDir, {db: memdb()}, function (err, dat) {
       t.error(err, 'no error')
       dat.joinNetwork(function () {
         t.pass('joinNetwork callback')
         t.same(dat.network.connected, 0, 'no connections')
-        dat.close(function () {
+        dat.close(function (err) {
+          t.error(err, 'no error')
           t.end()
         })
       })
@@ -211,9 +252,10 @@ test('download joinNetwork callback without connections', function (t) {
 
 test('download from snapshot', function (t) {
   var shareKey
+  var snapshotDat
   Dat(fixtures, {live: false}, function (err, dat) {
     t.error(err, 'live: false share, no error')
-    shareDat = dat
+    snapshotDat = dat
     dat.importFiles(function (err) {
       t.error(err, 'import no error')
       dat.archive.finalize(function (err) {
@@ -255,7 +297,10 @@ test('download from snapshot', function (t) {
 
             dat.close(function () {
               t.pass('close callback ok')
-              t.end()
+              snapshotDat.close(function () {
+                rimraf.sync(path.join(fixtures, '.dat'))
+                t.end()
+              })
             })
           })
         }
@@ -264,15 +309,6 @@ test('download from snapshot', function (t) {
   }
 })
 
-test('finished', function (t) {
-  shareDat.close(function () {
-    shareDat.db.close(function () {
-      rimraf.sync(path.join(fixtures, '.dat'))
-      t.end()
-    })
-  })
-})
-
 test.onFinish(function () {
   rimraf.sync(downloadDir)
 })