FirebaseStorage getData function (flutter#211)

* added FirebaseStorage getData func

* added getData tests

* bumped version and updated change log

* fix analyzer errors

* code style fixes

packages/firebase_storage/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.0.6
+
+* Added StorageReference getData function to download files into memory.
+
 ## 0.0.5+1
 
 * Aligned author name with rest of repo.

packages/firebase_storage/android/src/main/java/io/flutter/plugins/firebase/storage/FirebaseStoragePlugin.java

@@ -6,8 +6,10 @@
 
 import android.app.Activity;
 import android.net.Uri;
+import android.support.annotation.NonNull;
 import com.google.android.gms.tasks.OnFailureListener;
 import com.google.android.gms.tasks.OnSuccessListener;
+import com.google.android.gms.tasks.Task;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.storage.FirebaseStorage;
 import com.google.firebase.storage.StorageReference;
@@ -37,29 +39,61 @@ private FirebaseStoragePlugin(Activity activity) {
 
   @Override
   public void onMethodCall(MethodCall call, final Result result) {
-    if (call.method.equals("StorageReference#putFile")) {
-      Map<String, String> arguments = (Map<String, String>) call.arguments;
-      String filename = arguments.get("filename");
-      String path = arguments.get("path");
-      File file = new File(filename);
-      StorageReference ref = firebaseStorage.getReference().child(path);
-      UploadTask uploadTask = ref.putFile(Uri.fromFile(file));
-      uploadTask.addOnSuccessListener(
-          new OnSuccessListener<UploadTask.TaskSnapshot>() {
-            @Override
-            public void onSuccess(UploadTask.TaskSnapshot snapshot) {
-              result.success(snapshot.getDownloadUrl().toString());
-            }
-          });
-      uploadTask.addOnFailureListener(
-          new OnFailureListener() {
-            @Override
-            public void onFailure(Exception e) {
-              result.error("upload_error", e.getMessage(), null);
-            }
-          });
-    } else {
-      result.notImplemented();
+    switch (call.method) {
+      case "StorageReference#putFile":
+        putFile(call, result);
+        break;
+      case "StorageReference#getData":
+        getData(call, result);
+        break;
+      default:
+        result.notImplemented();
+        break;
     }
   }
+
+  private void putFile(MethodCall call, final Result result) {
+    Map<String, String> arguments = (Map<String, String>) call.arguments;
+    String filename = arguments.get("filename");
+    String path = arguments.get("path");
+    File file = new File(filename);
+    StorageReference ref = firebaseStorage.getReference().child(path);
+    UploadTask uploadTask = ref.putFile(Uri.fromFile(file));
+    uploadTask.addOnSuccessListener(
+        new OnSuccessListener<UploadTask.TaskSnapshot>() {
+          @Override
+          public void onSuccess(UploadTask.TaskSnapshot snapshot) {
+            result.success(snapshot.getDownloadUrl().toString());
+          }
+        });
+    uploadTask.addOnFailureListener(
+        new OnFailureListener() {
+          @Override
+          public void onFailure(Exception e) {
+            result.error("upload_error", e.getMessage(), null);
+          }
+        });
+  }
+
+  private void getData(MethodCall call, final Result result) {
+    Map<String, Object> arguments = (Map<String, Object>) call.arguments;
+    Integer maxSize = (Integer) arguments.get("maxSize");
+    String path = (String) arguments.get("path");
+    StorageReference ref = firebaseStorage.getReference().child(path);
+    Task<byte[]> downloadTask = ref.getBytes(maxSize);
+    downloadTask.addOnSuccessListener(
+        new OnSuccessListener<byte[]>() {
+          @Override
+          public void onSuccess(byte[] bytes) {
+            result.success(bytes);
+          }
+        });
+    downloadTask.addOnFailureListener(
+        new OnFailureListener() {
+          @Override
+          public void onFailure(@NonNull Exception e) {
+            result.error("download_error", e.getMessage(), null);
+          }
+        });
+  }
 }

packages/firebase_storage/ios/Classes/FirebaseStoragePlugin.m

@@ -41,24 +41,51 @@ - (instancetype)init {
 
 - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result {
   if ([@"StorageReference#putFile" isEqualToString:call.method]) {
-    NSData *data = [NSData dataWithContentsOfFile:call.arguments[@"filename"]];
-    NSString *path = call.arguments[@"path"];
-    FIRStorageReference *fileRef = [[FIRStorage storage].reference child:path];
-    [fileRef putData:data
-            metadata:nil
-          completion:^(FIRStorageMetadata *metadata, NSError *error) {
-            if (error != nil) {
-              result(error.flutterError);
-            } else {
-              // Metadata contains file metadata such as size,
-              // content-type, and download URL.
-              NSURL *downloadURL = metadata.downloadURL;
-              result(downloadURL.absoluteString);
-            }
-          }];
+    [self putFile:call result:result];
+  } else if ([@"StorageReference#getData" isEqualToString:call.method]) {
+    [self getData:call result:result];
   } else {
     result(FlutterMethodNotImplemented);
   }
 }
 
+- (void)putFile:(FlutterMethodCall *)call result:(FlutterResult)result {
+  NSData *data = [NSData dataWithContentsOfFile:call.arguments[@"filename"]];
+  NSString *path = call.arguments[@"path"];
+  FIRStorageReference *fileRef = [[FIRStorage storage].reference child:path];
+  [fileRef putData:data
+          metadata:nil
+        completion:^(FIRStorageMetadata *metadata, NSError *error) {
+          if (error != nil) {
+            result(error.flutterError);
+          } else {
+            // Metadata contains file metadata such as size,
+            // content-type, and download URL.
+            NSURL *downloadURL = metadata.downloadURL;
+            result(downloadURL.absoluteString);
+          }
+        }];
+}
+
+- (void)getData:(FlutterMethodCall *)call result:(FlutterResult)result {
+  NSNumber *maxSize = call.arguments[@"maxSize"];
+  NSString *path = call.arguments[@"path"];
+  FIRStorageReference *ref = [[FIRStorage storage].reference child:path];
+  [ref dataWithMaxSize:[maxSize longLongValue]
+            completion:^(NSData *_Nullable data, NSError *_Nullable error) {
+              if (error != nil) {
+                result(error.flutterError);
+                return;
+              }
+              if (data == nil) {
+                result(nil);
+                return;
+              }
+
+              FlutterStandardTypedData *dartData =
+                  [FlutterStandardTypedData typedDataWithBytes:data];
+              result(dartData);
+            }];
+}
+
 @end

packages/firebase_storage/lib/firebase_storage.dart

@@ -4,6 +4,7 @@
 
 import 'dart:async';
 import 'dart:io';
+import 'dart:typed_data';
 
 import 'package:flutter/services.dart';
 
@@ -27,12 +28,25 @@ class StorageReference {
     return new StorageReference._(childPath);
   }
 
+  /// Asynchronously uploads a file to the currently specified StorageReference, without additional metadata.
   StorageUploadTask put(File file) {
     final StorageUploadTask task =
         new StorageUploadTask._(file, _pathComponents.join("/"));
     task._start();
     return task;
   }
+
+  /// Asynchronously downloads the object at the StorageReference to a list in memory.
+  /// A list of the provided max size will be allocated.
+  Future<Uint8List> getData(int maxSize) {
+    return FirebaseStorage._channel.invokeMethod(
+      "StorageReference#getData",
+      <String, dynamic>{
+        'maxSize': maxSize,
+        'path': _pathComponents.join("/"),
+      },
+    );
+  }
 }
 
 class StorageUploadTask {

packages/firebase_storage/pubspec.yaml

@@ -3,7 +3,7 @@ name: firebase_storage
 description: Firebase Storage plugin for Flutter.
 author: Flutter Team <[email protected]>
 homepage: https://github.com/flutter/plugins/tree/master/packages/firebase_storage
-version: 0.0.5+1
+version: 0.0.6
 
 flutter:
   plugin:
@@ -14,5 +14,8 @@ dependencies:
   flutter:
     sdk: flutter
 
+dev_dependencies:
+  test: ^0.12.24
+
 environment:
     sdk: ">=1.8.0 <2.0.0"

packages/firebase_storage/test/firebase_storage_test.dart

@@ -0,0 +1,55 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:typed_data';
+
+import 'package:firebase_storage/firebase_storage.dart';
+import 'package:flutter/services.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('StorageReference', () {
+    group('getData', () {
+      const MethodChannel channel = const MethodChannel(
+        'firebase_storage',
+      );
+
+      final List<MethodCall> log = <MethodCall>[];
+
+      StorageReference ref;
+
+      setUp(() {
+        channel.setMockMethodCallHandler((MethodCall methodCall) {
+          log.add(methodCall);
+          return new Future<Uint8List>.value(
+              new Uint8List.fromList(<int>[1, 2, 3, 4]));
+        });
+        ref = FirebaseStorage.instance
+            .ref()
+            .child('avatars')
+            .child('large')
+            .child('image.jpg');
+      });
+
+      test('invokes correct method', () async {
+        await ref.getData(10);
+
+        expect(
+            log,
+            equals(<MethodCall>[
+              new MethodCall('StorageReference#getData', <String, dynamic>{
+                'maxSize': 10,
+                'path': 'avatars/large/image.jpg',
+              }),
+            ]));
+      });
+
+      test('returns correct result', () async {
+        expect(await ref.getData(10),
+            equals(new Uint8List.fromList(<int>[1, 2, 3, 4])));
+      });
+    });
+  });
+}