add support for chunked uploads

README.md

@@ -52,6 +52,8 @@ OR, if you just want to start playing with the library run...
     shares              <-- create link to view file
     media               <-- create streamable link to file
     thumbnails          <-- get thumbnail of file
+    chunk               <-- upload a chunk of a large file
+    commit_chunks       <-- complete a chunked upload
     copyref             <-- create copy reference to file
     delta               <-- get list of delta entries
     stream              <-- creates readable stream
@@ -468,6 +470,57 @@ output of `metadata` returns...
       "size": "762.5 KB"
     } 
 
+### chunk(body, [options,] cb)
+
+Uploads large files to Dropbox in multiple chunks. Also has the ability to resume if the upload is interrupted. This allows for uploads larger than the /files and /files_put maximum of 150 MB. Note that chunks must be submitted in order, else the response will be a 400 error that includes the current offset.
+
+    client.chunk("some data", {offset: 0, upload_id: null}, function(status, reply){
+      console.dir(reply);
+
+      require('fs').writeFile('koala_small.jpg', reply, function () {
+        console.log('Thumbnail saved!');
+      });
+    })
+
+output of `reply` returns...
+
+    {
+      expires: 'Fri, 25 Oct 2013 04:51:52 +0000',
+      upload_id: 'nLkA-eBpXUcr07JPq_ShRA',
+      offset: 4
+    }
+
+Typical usage:
+
+1. Send your first chunk of your file to `chunk` and receive an upload_id in the reply.
+2. Repeatedly submit subsequent chunks using the upload_id to identify the upload in progress and an offset representing the number of bytes transferred so far.
+3. After each chunk has been uploaded, the server returns a new offset representing the total amount transferred.
+4. After the last chunk, call `commit_chunks` to complete the upload.
+
+### commit_chunks(path, [options,] callback)
+
+Completes an upload initiated by `chunk`. Similar to `put`, but takes an `upload_id` instead of `data`.
+
+    client.commit_chunks(filename, {upload_id: 'nLkA-eBpXUcr07JPq_ShRA'}, function(status, reply){
+      console.dir(reply)
+    })
+
+output of `reply` returns...
+
+    {
+      "size": "225.4KB",
+      "rev": "35e97029684fe",
+      "thumb_exists": false,
+      "bytes": 230783,
+      "modified": "Tue, 19 Jul 2011 21:55:38 +0000",
+      "path": "/foo/hello.txt",
+      "is_dir": false,
+      "icon": "page_white_text",
+      "root": "sandbox",
+      "mime_type": "text/plain",
+      "revision": 220823
+    }
+
 ### cpref(path, [options,] callback)
 
     client.cpref("song.mp3", function(status, reply){

lib/dbox.js

@@ -195,6 +195,60 @@ exports.app = function(config){
           })
         },
 
+        chunk: function(body, args, cb){
+          if(!cb){
+            cb   = args
+            args = {}
+          }
+
+          var signature = helpers.sign(options, args)
+
+          var url = helpers.url({
+            hostname: "api-content.dropbox.com",
+            action: "chunked_upload",
+            // path: path,
+            root: "",
+            query: signature
+          });
+
+          args["method"] = "PUT";
+          args["headers"] = { "content-length": body.length };
+          args["url"] = url;
+
+          // do not send empty body
+          if(body.length > 0) args["body"] = body
+
+          return request(args, function(e, r, b){
+            cb(e ? null : r.statusCode, e ? null : helpers.parseJSON(b))
+          })
+        },
+
+        commit_chunks: function(path, args, cb){
+          if(!cb){
+            cb   = args
+            args = null
+          }
+
+          var signature = helpers.sign(options, args)
+
+          var url = helpers.url({
+            hostname: "api-content.dropbox.com",
+            action: "commit_chunked_upload",
+            path: path,
+            query: signature
+          })
+
+          var args = {
+            "method": "POST",
+            "url": url
+          }
+
+          return request(args, function(e, r, b){
+            cb(e ? null : r.statusCode, e ? null : helpers.parseJSON(b))
+          })
+        },
+
+
         metadata: function(path, args, cb){
           if(!cb){
             cb   = args

lib/helpers.js

@@ -112,6 +112,9 @@ module.exports = function(config){
 
       // fileops calls desn't want root in path
       var rootpath = fileop ? "" : root
+
+      // override rootpath if obj.root is specified
+      if(typeof obj.root !== "undefined" && obj.root !== null) rootpath = obj.root;
 
       // fileops calls desn't want scope in path
       var scopepath = fileop ? "" : scope

test/all.js

@@ -48,7 +48,7 @@ describe("all", function(){
       done()
     })
   })
-  
+
   it("should get metadatq of file", function(done) {
     client.metadata("myfirstfile.txt", function(status, reply){
       status.should.eql(200)