Rename! gitswarm->gittorrent

1 files changed, 132 insertions, 0 deletions

diff --git a/git-remote-gittorrent b/git-remote-gittorrent
new file mode 100755
index 0000000..a8bcb9d
--- /dev/null
+++ b/git-remote-gittorrent
@@ -0,0 +1,132 @@
+#!/usr/bin/env node
+
+var Chalk = require('chalk')
+var DHT = require('bittorrent-dht')
+var exec = require('child_process').exec
+var fs = require('fs')
+var magnet = require('magnet-uri')
+var spawn = require('child_process').spawn
+var Swarm = require('bittorrent-swarm')
+var ut_gittorrent = require('ut_gittorrent')
+var WebTorrent = require('webtorrent')
+
+function die (error) {
+  console.error(error)
+  process.exit(1)
+}
+
+// Gotta enable color manually because stdout isn't a tty.
+var chalk = new Chalk.constructor({enabled: true});
+
+var dht = new DHT({
+  bootstrap: ['three.printf.net:6882']
+})
+
+var url = process.argv[3]
+var matches = url.match(/gittorrent:\/\/([a-f0-9]{40})\/(.*)/)
+if (matches) {
+  var key = matches[1]
+  var reponame = matches[2]
+  dht.on('ready', function () {
+    var val = new Buffer(key, 'hex')
+    dht.get(val, function (err, res) {
+      if (err) {
+        return console.error(err)
+      }
+      var json = res.v.toString()
+      var repos = JSON.parse(json)
+      console.warn('\nMutable key ' + chalk.green(key) + ' returned:\n' + chalk.yellow(json))
+      get_infohash(repos.repositories[reponame].master)
+    })
+  })
+} else {
+  url = url.replace(/^gittorrent:/i, 'git:')
+  exec('git ls-remote ' + url + ' HEAD', function (err, stdout, stderr) {
+    if (err !== null) {
+      die(err)
+    }
+    var lines = stdout.split('\n')
+    if (lines.length !== 2) {
+      die("Didn't get back a single HEAD ref: " + lines)
+    }
+    var line = lines[0].split('\t')
+    var ref = line[0]
+    var head = line[1]
+    if (head !== 'HEAD') {
+      die("Couldn't parse the ref line: " + ref, head)
+    }
+    if (ref.length !== 40) {
+      die('Was expecting a 40-byte sha: ' + ref)
+    }
+    dht.on('ready', function () {
+      get_infohash(ref)
+    })
+  })
+}
+
+function get_infohash (ref) {
+  // We use console.warn (stderr) because git ignores our writes to stdout.
+  console.warn('\nOkay, we want to get: ' + chalk.green(ref) + '\n')
+
+  process.stdin.setEncoding('utf8')
+  process.stdin.on('readable', function () {
+    var chunk = process.stdin.read()
+    if (chunk === 'capabilities\n') {
+      process.stdout.write('fetch\n\n')
+    }
+    if (chunk === 'list\n') {
+      process.stdout.write(ref + ' refs/heads/master\n\n')
+    }
+  })
+  process.stdout.on('error', function () {
+    // stdout was closed
+  })
+
+  var magnetUri = 'magnet:?xt=urn:btih:' + ref
+  var parsed = magnet(magnetUri)
+  dht.lookup(parsed.infoHash)
+
+  dht.on('peer', function (addr, hash, from) {
+    swarm.addPeer(addr)
+  })
+
+  var swarm = new Swarm(parsed.infoHash, 'cafebabecafebabecafecafebabecafebabecafe')
+  swarm.on('wire', function (wire, addr) {
+    console.warn('Adding swarm peer: ' + chalk.green(addr) + '\n')
+    wire.use(ut_gittorrent())
+    wire.ut_gittorrent.on('handshake', function () {
+      wire.ut_gittorrent.ask(parsed.infoHash)
+    })
+    wire.ut_gittorrent.on('receivedTorrent', function (infoHash) {
+      var client = new WebTorrent({
+        dht: {
+          bootstrap: ['three.printf.net:6882']
+        },
+        tracker: false
+      })
+      client.download(infoHash, function (torrent) {
+        console.warn('Downloading git pack with infohash: ' + chalk.green(infoHash) + '\n')
+        torrent.on('done', function (done) {
+          var filename = torrent.storage.path + '/' + torrent.files[0].path
+          var unpack = spawn('git', ['index-pack', '--stdin', '-v', '--fix-thin'])
+          var stream = fs.createReadStream(filename)
+          stream.on('open', function () {
+            stream.pipe(unpack.stdin)
+          })
+          unpack.stderr.pipe(process.stderr)
+          unpack.on('exit', function (code) {
+            var targetdir = process.env['GIT_DIR']
+            var stream = fs.createWriteStream(targetdir + '/refs/heads/master')
+            stream.once('open', function (fd) {
+              stream.write(ref + '\n')
+              stream.end()
+              // These writes are actually necessary for git to finish checkout.
+              process.stdout.write('\n\n')
+              process.exit()
+            })
+          })
+        })
+      })
+    })
+  })
+}