Stream video with GridStoreAdapter (implements byte-range requests)

spec/ParseFile.spec.js

@@ -491,6 +491,27 @@ describe('Parse.File testing', () => {
     });
   });
 
+  it('supports byte-range requests when requesting a video', done => {
+    var headers = {
+      'Content-Type': 'video/mp4',
+      'X-Parse-Application-Id': 'test',
+      'X-Parse-REST-API-Key': 'rest'
+    };
+    request.post({
+      headers: headers,
+      url: 'http://localhost:8378/1/files/file',
+      body: '101010101001010101010101010101010010110101010101010101010'
+    }, (error, response, body) => {
+      expect(error).toBe(null);
+      var b = JSON.parse(body);
+      request.get(b.url, (error, response, body) =>{
+        expect(response.headers['content-type']).toMatch(/^video\/mp4/);
+        expect(response.headers['accept-ranges']).toMatch(/^bytes/);
+        done();
+      });
+    });
+  });
+
   it_exclude_dbs(['postgres'])('creates correct url for old files hosted on files.parsetfss.com', done => {
     var file = {
       __type: 'File',

src/Adapters/Files/GridStoreAdapter.js

@@ -67,6 +67,116 @@ export class GridStoreAdapter extends FilesAdapter {
   getFileLocation(config, filename) {
     return (config.mount + '/files/' + config.applicationId + '/' + encodeURIComponent(filename));
   }
+
+  handleVideoStream(filename, range, res, contentType) {
+    return this._connect().then(database => {
+      return GridStore.exist(database, filename)
+        .then(() => {
+          let gridStore = new GridStore(database, filename, 'r');
+          gridStore.open((err, gridFile) => {
+              if(!gridFile) {
+                  res.status(404);
+                  res.set('Content-Type', 'text/plain');
+                  res.end('File not found.');
+                  return;
+                }
+                streamVideo(gridFile,range, res, contentType);
+          });
+        });
+    });
+  }
+}
+
+  /**
+  * streamVideo is licensed under Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).
+  * Author: LEROIB at weightingformypizza.(https://weightingformypizza.wordpress.com/2015/06/24/stream-html5-media-content-like-video-audio-from-mongodb-using-express-and-gridstore/)
+  */
+function streamVideo(gridFile, range, res, contentType) {
+  var buffer_size = 1024 * 1024;//1024Kb
+  if (range != null) {
+    // Range request, partiall stream the file
+    var parts = range.replace(/bytes=/, "").split("-");
+    var partialstart = parts[0];
+    var partialend = parts[1];
+    var start = partialstart ? parseInt(partialstart, 10) : 0;
+    var end = partialend ? parseInt(partialend, 10) : gridFile.length - 1;
+    var chunksize = (end - start) + 1;
+
+    if(chunksize == 1){
+      start = 0;
+      partialend = false;
+    }
+
+    if(!partialend){
+      if(((gridFile.length-1) - start) < (buffer_size)){
+          end = gridFile.length - 1;
+      }else{
+        end = start + (buffer_size);
+      }
+        chunksize = (end - start) + 1;
+    }
+
+    if(start == 0 && end == 2){
+      chunksize = 1;
+    }
+
+    res.writeHead(206, {
+        'Content-Range': 'bytes ' + start + '-' + end + '/' + gridFile.length,
+        'Accept-Ranges': 'bytes',
+        'Content-Length': chunksize,
+        'Content-Type': contentType,
+      });
+
+    gridFile.seek(start, function () {
+      // get gridFile stream
+              var stream = gridFile.stream(true);
+              var ended = false;
+              var bufferIdx = 0;
+              var bufferAvail = 0;
+              var range = (end - start) + 1;
+              var totalbyteswanted = (end - start) + 1;
+              var totalbyteswritten = 0;
+              // write to response
+              stream.on('data', function (buff) {
+              bufferAvail += buff.length;
+              //Ok check if we have enough to cover our range
+              if(bufferAvail < range) {
+              //Not enough bytes to satisfy our full range
+                  if(bufferAvail > 0)
+                  {
+                  //Write full buffer
+                    res.write(buff);
+                    totalbyteswritten += buff.length;
+                    range -= buff.length;
+                    bufferIdx += buff.length;
+                    bufferAvail -= buff.length;
+                  }
+              }
+              else{
+              //Enough bytes to satisfy our full range!
+                  if(bufferAvail > 0) {
+                    var buffer = buff.slice(0,range);
+                    res.write(buffer);
+                    totalbyteswritten += buffer.length;
+                    bufferIdx += range;
+                    bufferAvail -= range;
+                  }
+              }
+              if(totalbyteswritten >= totalbyteswanted) {
+              //  totalbytes = 0;
+                gridFile.close();
+                res.end();
+                this.destroy();
+              }
+              });
+          });
+    }else{
+          // stream back whole file
+        res.header("Accept-Ranges", "bytes");
+        res.header('Content-Type', contentType);
+        res.header('Content-Length', gridFile.length);
+        var stream = gridFile.stream(true).pipe(res);
+  }
 }
 
 export default GridStoreAdapter;

src/Controllers/FilesController.js

@@ -82,6 +82,19 @@ export class FilesController extends AdaptableController {
   expectedAdapterType() {
     return FilesAdapter;
   }
+
+
+    /**
+    * Stream video file by serving data in chunks if FilesAdapter is GridStoreAdapter.
+    * If not; handle the request as usual with "getFileData".
+    */
+  handleVideoStream(filename, range, res, contentType) {
+      if (this.adapter.constructor.name == 'GridStoreAdapter') {
+        return this.adapter.handleVideoStream(filename,range,res,contentType);
+      }else{
+        return this.adapter.getFileData(filename);
+      }
+   }
 }
 
 export default FilesController;

src/Routers/FilesRouter.js

@@ -36,16 +36,24 @@ export class FilesRouter {
     const config = new Config(req.params.appId);
     const filesController = config.filesController;
     const filename = req.params.filename;
-    filesController.getFileData(config, filename).then((data) => {
-      res.status(200);
-      var contentType = mime.lookup(filename);
-      res.set('Content-Type', contentType);
-      res.end(data);
-    }).catch((err) => {
-      res.status(404);
-      res.set('Content-Type', 'text/plain');
-      res.end('File not found.');
-    });
+    const contentType = mime.lookup(filename);
+    if (contentType == 'video/mp4' || contentType == 'video/quicktime') {
+      filesController.handleVideoStream(filename, req.get("Range"), res, contentType).catch((err) => {
+        res.status(404);
+        res.set('Content-Type', 'text/plain');
+        res.end('File not found.');
+      });
+    }else{
+      filesController.getFileData(config, filename).then((data) => {
+        res.status(200);
+        res.set('Content-Type', contentType);
+        res.end(data);
+      }).catch((err) => {
+        res.status(404);
+        res.set('Content-Type', 'text/plain');
+        res.end('File not found.');
+      });
+    }
   }
 
   createHandler(req, res, next) {