[firebase_storage] Fix Content-Type auto-detection for Android (flutter#1834)

Author: long1eu

packages/firebase_storage/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 3.0.3
+
+* Fix inconsistency of `getPath`, on Android the path returned started with a `/` but on iOS it did not
+* Fix content-type auto-detection on Android
+
 ## 3.0.2
 
 * Automatically use version from pubspec.yaml when reporting usage to Firebase.

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

@@ -6,6 +6,7 @@
 
 import android.net.Uri;
 import android.util.SparseArray;
+import android.webkit.MimeTypeMap;
 import androidx.annotation.NonNull;
 import com.google.android.gms.tasks.OnCompleteListener;
 import com.google.android.gms.tasks.OnFailureListener;
@@ -49,7 +50,7 @@ private FirebaseStoragePlugin(MethodChannel channel, Registrar registrar) {
   }
 
   @Override
-  public void onMethodCall(MethodCall call, final Result result) {
+  public void onMethodCall(@NonNull MethodCall call, @NonNull final Result result) {
     String app = call.argument("app");
     String storageBucket = call.argument("bucket");
     if (app == null && storageBucket == null) {
@@ -258,15 +259,13 @@ public void onFailure(@NonNull Exception e) {
   private void putFile(MethodCall call, Result result) {
     String filename = call.argument("filename");
     String path = call.argument("path");
-    Map<String, Object> metadata = call.argument("metadata");
     File file = new File(filename);
+    final Uri fileUri = Uri.fromFile(file);
+    Map<String, Object> metadata = call.argument("metadata");
+    metadata = ensureMimeType(metadata, fileUri);
+
     StorageReference ref = firebaseStorage.getReference().child(path);
-    UploadTask uploadTask;
-    if (metadata == null) {
-      uploadTask = ref.putFile(Uri.fromFile(file));
-    } else {
-      uploadTask = ref.putFile(Uri.fromFile(file), buildMetadataFromMap(metadata));
-    }
+    final UploadTask uploadTask = ref.putFile(fileUri, buildMetadataFromMap(metadata));
     final int handle = addUploadListeners(uploadTask);
     result.success(handle);
   }
@@ -394,7 +393,7 @@ private void cancelUploadTask(MethodCall call, final Result result) {
     }
   }
 
-  private void resumeUploadTask(MethodCall call, final Result result) {
+  private void resumeUploadTask(MethodCall call, @NonNull final Result result) {
     int handle = call.argument("handle");
     UploadTask task = uploadTasks.get(handle);
     if (task != null) {
@@ -487,4 +486,25 @@ private Map<String, Object> buildMapFromTaskSnapshot(
     }
     return map;
   }
+
+  private Map<String, Object> ensureMimeType(Map<String, Object> metadata, Uri file) {
+    if (metadata == null) {
+      metadata = new HashMap<>();
+    }
+
+    if (metadata.get("contentType") == null) {
+      metadata.put("contentType", getMimeType(file));
+    }
+
+    return metadata;
+  }
+
+  private static String getMimeType(Uri file) {
+    String type = null;
+    String extension = MimeTypeMap.getFileExtensionFromUrl(file.toString());
+    if (extension != null) {
+      type = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
+    }
+    return type;
+  }
 }

packages/firebase_storage/example/pubspec.yaml

@@ -8,7 +8,7 @@ dependencies:
   firebase_storage:
     path: ../
   firebase_core: ^0.4.0
-  uuid: "^1.0.0"
+  uuid: ^1.0.0
   http: ^0.12.0
 
 dev_dependencies:

packages/firebase_storage/lib/src/storage_reference.dart

@@ -88,12 +88,18 @@ class StorageReference {
   /// Returns the full path to this object, not including the Google Cloud
   /// Storage bucket.
   Future<String> getPath() async {
-    return await FirebaseStorage.channel
+    final String path = await FirebaseStorage.channel
         .invokeMethod<String>("StorageReference#getPath", <String, String>{
       'app': _firebaseStorage.app?.name,
       'bucket': _firebaseStorage.storageBucket,
       'path': _pathComponents.join("/"),
     });
+
+    if (path.startsWith('/')) {
+      return path.substring(1);
+    } else {
+      return path;
+    }
   }
 
   /// Returns the short name of this object.

packages/firebase_storage/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for Firebase Cloud Storage, a powerful, simple, and
   cost-effective object storage service for Android and iOS.
 author: Flutter Team <[email protected]>
 homepage: https://github.com/flutter/plugins/tree/master/packages/firebase_storage
-version: 3.0.2
+version: 3.0.3
 
 flutter:
   plugin: