added blob 'checkout' on open in new window

app/lib/blob-protocol.js

@@ -1,13 +0,0 @@
-var protocol = require('protocol')
-var path = require('path')
-var toPath = require('multiblob/util').toPath
-
-module.exports = function (config) {
-  var dir = path.join(config.path, 'blobs')
-  return function (request) {
-    var id = request.url.split(':')[1]
-    if (request.method == 'GET' && id) {
-      return new protocol.RequestFileJob(toPath(dir, id))
-    }
-  }
-}

app/lib/blobs.js

@@ -0,0 +1,93 @@
+var path = require('path')
+var multicb = require('multicb')
+var toPath = require('multiblob/util').toPath
+var querystring = require('querystring')
+var fs = require('fs')
+
+// blob url parser
+var re = /^blob:([a-z0-9\+\/=]+\.blake2s)\??(.*)$/i
+var url_parse =
+module.exports.url_parse = function (str) {
+  var parts = re.exec(str)
+  if (parts)
+    return { hash: parts[1], qs: querystring.parse(parts[2]) }
+}
+
+// blob url builder
+var url_stringify =
+module.exports.url_stringify = function (hash, qs) {
+  var url = 'blob:'+hash
+  if (qs && typeof qs == 'object')
+    url += '?' + querystring.stringify(qs)
+  return url
+}
+
+module.exports = function (blobs_dir, checkout_dir) {
+  return {
+    // behavior for the blob: protocol
+    protocol: function (request) {
+      var protocol = require('protocol') // have to require here, doing so before app:ready causes errors
+      // simple fetch
+      var parsed = url_parse(request.url)
+      if (request.method == 'GET' && parsed) {
+        return new protocol.RequestFileJob(toPath(blobs_dir, parsed.hash))
+      }
+    },
+
+    // copy file from blobs into given dir with nice name
+    checkout: function (url, cb) {
+      var parsed = url_parse(url)
+      if (!parsed)
+        return cb({ badUrl: true })
+      
+      var filename = parsed.qs.name || parsed.qs.filename || parsed.hash
+
+      // check if we have the blob, at the same time find an available filename
+      var done = multicb({ pluck: 1 })
+      fs.stat(toPath(blobs_dir, parsed.hash), done())
+      findFreeCheckoutPath(filename, done())
+      done(function (err, res) {
+        if (!res[0])
+          return cb({ notFound: true })
+
+        // copy the file
+        var src = toPath(blobs_dir, parsed.hash)
+        var dst = res[1]
+        var read = fs.createReadStream(src)
+        var write = fs.createWriteStream(dst)
+        read.on('error', done)
+        write.on('error', done)
+        write.on('close', done)
+        read.pipe(write)
+        function done (err) {
+          cb && cb(err, dst)
+          cb = null
+        }
+      })
+    }
+  }
+
+  // helper to create a filename in checkout_dir that isnt already in use
+  function findFreeCheckoutPath (filename, cb) {
+    var n = 1
+    var parsed = path.parse(filename)
+    next()
+
+    function gen () {
+      var name = parsed.name
+      if (n !== 1) name += ' ('+n+')'
+      name += parsed.ext
+      n++
+      return path.join(checkout_dir, name)
+    }
+
+    function next () {
+      var filepath = gen()
+      fs.stat(filepath, function (err, stat) {
+        if (!stat)
+          return cb(null, filepath)
+        next()
+      })
+    }
+  }
+}