Add file download to node example (#530)

* Add file download to node example

* Set validation: false

* Set X-Goog-Hash header on download response

* Add both crc32c and md5

* Remove fixed comment.

* Don't set empty content-type header on download

Temporary workaround for #532 so we can get this PR in.

Co-authored-by: francisco souza <108725+fsouza@users.noreply.github.com>
Co-authored-by: francisco souza <fsouza@users.noreply.github.com>

examples/node/docker-compose.yaml

@@ -0,0 +1,9 @@
+services:
+  storage:
+    image: fsouza/fake-gcs-server
+    build: ../../
+    ports:
+      - 8080:8080
+    volumes:
+      - ../data:/data
+    command: ["-scheme", "http", "-port", "8080", "-external-url", "http://localhost:8080", "-backend", "memory"]

examples/node/index.js

@@ -1,4 +1,4 @@
-async function listBuckets() {
+async function run() {
   // [START storage_list_buckets]
   // Imports the Google Cloud client library
   const { Storage } = require("@google-cloud/storage");
@@ -16,9 +16,16 @@ async function listBuckets() {
     console.log(bucket.id);
   });
   // [END storage_list_buckets]
+
+  const [content] = await storage.bucket('sample-bucket')
+    .file('some_file.txt')
+    .download();
+  console.log("Contents:")
+  console.log(content.toString())
 }
 
-listBuckets().catch((err) => {
+
+run().catch((err) => {
   console.error(err);
   process.exit(1);
 });

examples/node/package.json

@@ -4,6 +4,7 @@
   "description": "",
   "main": "index.js",
   "scripts": {
+    "run": "node index.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "author": "",

fakestorage/object.go

@@ -558,10 +558,13 @@ func (s *Server) downloadObject(w http.ResponseWriter, r *http.Request) {
 		status = http.StatusPartialContent
 		w.Header().Set("Content-Range", fmt.Sprintf("bytes %d-%d/%d", start, end, len(obj.Content)))
 	}
+	if obj.ContentType != "" {
+		w.Header().Set(contentTypeHeader, obj.ContentType)
+	}
 	w.Header().Set("Accept-Ranges", "bytes")
 	w.Header().Set("Content-Length", strconv.Itoa(len(content)))
-	w.Header().Set(contentTypeHeader, obj.ContentType)
 	w.Header().Set("X-Goog-Generation", strconv.FormatInt(obj.Generation, 10))
+	w.Header().Set("X-Goog-Hash", fmt.Sprintf("crc32c=%s,md5=%s", obj.Crc32c, obj.Md5Hash))
 	w.Header().Set("Last-Modified", obj.Updated.Format(http.TimeFormat))
 	if obj.ContentEncoding != "" {
 		w.Header().Set("Content-Encoding", obj.ContentEncoding)