fix: Support empty objects (size 0) (#6)

widdix · May 24, 2023 · de4a336 · de4a336
1 parent ae6ab2d
commit de4a336
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Showing 2 changed files with 96 additions and 11 deletions.
diff --git a/index.js b/index.js
@@ -405,7 +405,13 @@ function getObject({Bucket, Key, VersionId, PartNumber, Range}, timeout, cb) {
             if (err) {
               cb(err);
             } else {
-              if (res.statusCode === 206) {
+              if (res.statusCode === 200 && body.length === 0) {
+                const data = {
+                  Body: body,
+                  ContentLength: body.length
+                };
+                cb(null, data);
+              } else if (res.statusCode === 206) {
                 const data = {
                   Body: body,
                   ContentLength: body.length
@@ -578,19 +584,27 @@ exports.download = ({bucket, key, version}, {partSizeInMegabytes, concurrency, c
         partsDownloading[1] = getObject(params, timeout, (err, data) => {
           delete partsDownloading[1];
           if (err) {
-            reject(err);
+            if (err.code === 'InvalidRange') {
+              resolve({metadata: {lengthInBytes: 0}, body: Buffer.alloc(0)});
+            } else {
+              reject(err);
+            }
           } else {
-            const contentRange = parseContentRange(data.ContentRange);
-            if (contentRange === undefined) {
-              reject(new Error(`unexpected S3 content range: ${data.ContentRange}`));
+            if (data.ContentLength === 0) {
+              resolve({metadata: {lengthInBytes: 0}, body: Buffer.alloc(0)});
             } else {
-              const metadata = {
-                lengthInBytes: contentRange.length
-              };
-              if ('PartsCount' in data) {
-                metadata.parts = data.PartsCount;
+              const contentRange = parseContentRange(data.ContentRange);
+              if (contentRange === undefined) {
+                reject(new Error(`unexpected S3 content range: ${data.ContentRange}`));
+              } else {
+                const metadata = {
+                  lengthInBytes: contentRange.length
+                };
+                if ('PartsCount' in data) {
+                  metadata.parts = data.PartsCount;
+                }
+                resolve({metadata, body: data.Body});
               }
-              resolve({metadata, body: data.Body});
             }
           }
         });

diff --git a/test/index.js b/test/index.js
@@ -345,6 +345,42 @@ describe('index', () => {
                 );
               });
             });
+            it('empty file', (done) => {
+              nock('https://bucket.s3.eu-west-1.amazonaws.com', {
+                reqheaders: {
+                  'x-amz-content-sha256': /.*/,
+                  'x-amz-date': /.*/,
+                  authorization: /.*/
+                }
+              })
+                .get('/key')
+                .query({
+                  versionId: 'version',
+                  partNumber: '1'
+                })
+                .reply(206, Buffer.alloc(0), {
+                  'Content-Length': '0',
+                  'Content-Type': 'text/plain'
+                });
+              mockfs({
+                '/tmp': {
+                }
+              });
+              pipeline(
+                download({bucket:'bucket', key: 'key', version: 'version'}, {concurrency: 4}).readStream(),
+                fs.createWriteStream('/tmp/test'),
+                (err) => {
+                  if (err) {
+                    done(err);
+                  } else {
+                    assert.ok(nock.isDone());
+                    const {size} = fs.statSync('/tmp/test');
+                    assert.deepStrictEqual(size, 0);
+                    done();
+                  }
+                }
+              );
+            });
             it('happy', (done) => {
               const bytes = 1000000;
               nockPart(1000000, 1, 1, bytes);
@@ -645,6 +681,41 @@ describe('index', () => {
                 }
               );
             });
+            it('empty file', (done) => {
+              nock('https://bucket.s3.eu-west-1.amazonaws.com', {
+                reqheaders: {
+                  range: 'bytes=0-7999999',
+                  'x-amz-content-sha256': /.*/,
+                  'x-amz-date': /.*/,
+                  authorization: /.*/
+                }
+              })
+                .get('/key')
+                .query({
+                  versionId: 'version'
+                })
+                .reply(416, '<?xml version="1.0" encoding="UTF-8"?>\n<Error><Code>InvalidRange</Code><Message>The requested range is not satisfiable</Message><RangeRequested>bytes=0-7999999</RangeRequested><ActualObjectSize>0</ActualObjectSize><RequestId>X98GTEXW2R90YZ2Y</RequestId><HostId>n/pHIOHiOaojuuH5uQ2JGqASSO3cPPCqrb1fHBJAVEdRu/XDLCR1VMwcVCUSv4DwwfKMxSY9wBQ=</HostId></Error>', {
+                  'Content-Type': 'application/xml'
+                });
+              mockfs({
+                '/tmp': {
+                }
+              });
+              pipeline(
+                download({bucket:'bucket', key: 'key', version: 'version'}, {partSizeInMegabytes: 8, concurrency: 4}).readStream(),
+                fs.createWriteStream('/tmp/test'),
+                (err) => {
+                  if (err) {
+                    done(err);
+                  } else {
+                    assert.ok(nock.isDone());
+                    const {size} = fs.statSync('/tmp/test');
+                    assert.deepStrictEqual(size, 0);
+                    done();
+                  }
+                }
+              );
+            });
             it('happy', (done) => {
               const bytes = 1000000;
               nockRange(0, 7999999, bytes);