Support byte range requests (#71)

* Support Byte Range Requests

See parse-community/parse-server#6028

* use promises

* Add Tests

* rename getFileStream to handleFileStream

Author: dplewis

index.js

@@ -144,5 +144,33 @@ S3Adapter.prototype.getFileLocation = function(config, filename) {
   return (config.mount + '/files/' + config.applicationId + '/' + filename);
 }
 
+S3Adapter.prototype.handleFileStream = function (filename, req, res) {
+  const params = {
+    Key: this._bucketPrefix + filename,
+    Range: req.get('Range'),
+  };
+  return this.createBucket().then(() => {
+    return new Promise((resolve, reject) => {
+      this._s3Client.getObject(params, (error, data) => {
+        if (error !== null) {
+          return reject(error);
+        }
+        if (data && !data.Body) {
+          return reject(data);
+        }
+        res.writeHead(206, {
+          'Accept-Ranges': data.AcceptRanges,
+          'Content-Length': data.ContentLength,
+          'Content-Range': data.ContentRange,
+          'Content-Type': data.ContentType,
+        });
+        res.write(data.Body);
+        res.end();
+        resolve(data.Body);
+      });
+    });
+  });
+}
+
 module.exports = S3Adapter;
 module.exports.default = S3Adapter;

spec/test.spec.js

@@ -153,6 +153,88 @@ describe('S3Adapter tests', () => {
     });
   });
 
+  describe('getFileStream', () => {
+    it('should handle range bytes', () => {
+      const s3 = new S3Adapter('accessKey', 'secretKey', 'myBucket');
+      s3._s3Client = {
+        createBucket: callback => callback(),
+        getObject: (params, callback) => {
+          const { Range } = params;
+
+          expect(Range).toBe('bytes=0-1');
+
+          const data = {
+            Body: Buffer.from('hello world', 'utf8'),
+          };
+          callback(null, data);
+        },
+      };
+      const req = {
+        get: () => 'bytes=0-1',
+      };
+      const resp = {
+        writeHead: jasmine.createSpy('writeHead'),
+        write: jasmine.createSpy('write'),
+        end: jasmine.createSpy('end'),
+      };
+      s3.handleFileStream('test.mov', req, resp).then((data) => {
+        expect(data.toString('utf8')).toBe('hello world');
+        expect(resp.writeHead).toHaveBeenCalled();
+        expect(resp.write).toHaveBeenCalled();
+        expect(resp.end).toHaveBeenCalled();
+      });
+    });
+
+    it('should handle range bytes error', () => {
+      const s3 = new S3Adapter('accessKey', 'secretKey', 'myBucket');
+      s3._s3Client = {
+        createBucket: callback => callback(),
+        getObject: (params, callback) => {
+          callback('FileNotFound', null);
+        },
+      };
+      const req = {
+        get: () => 'bytes=0-1',
+      };
+      const resp = {
+        writeHead: jasmine.createSpy('writeHead'),
+        write: jasmine.createSpy('write'),
+        end: jasmine.createSpy('end'),
+      };
+      s3.handleFileStream('test.mov', req, resp).catch((error) => {
+        expect(error).toBe('FileNotFound');
+        expect(resp.writeHead).not.toHaveBeenCalled();
+        expect(resp.write).not.toHaveBeenCalled();
+        expect(resp.end).not.toHaveBeenCalled();
+      });
+    });
+
+    it('should handle range bytes no data', () => {
+      const s3 = new S3Adapter('accessKey', 'secretKey', 'myBucket');
+      const data = { Error: 'NoBody' };
+      s3._s3Client = {
+        createBucket: callback => callback(),
+        getObject: (params, callback) => {
+          callback(null, data);
+        },
+      };
+      const req = {
+        get: () => 'bytes=0-1',
+      };
+      const resp = {
+        writeHead: jasmine.createSpy('writeHead'),
+        write: jasmine.createSpy('write'),
+        end: jasmine.createSpy('end'),
+      };
+      s3.handleFileStream('test.mov', req, resp).catch((error) => {
+        expect(error).toBe(data);
+        expect(resp.writeHead).not.toHaveBeenCalled();
+        expect(resp.write).not.toHaveBeenCalled();
+        expect(resp.end).not.toHaveBeenCalled();
+      });
+    });
+  });
+
   describe('getFileLocation', () => {
     var config = {
       mount: 'http://my.server.com/parse',