[image_picker_android] Name picked files to match the original filenames where possible (#6096)

* [image_picker_android] Name picked files to match the original filenames where possible.

* [image_picker_android] Update CHANGELOG.md

* [image_picker_android] Add license blocks

* [image_picker_android] Clear imports, document FileUtils.getPathFromUri

* [image_picker_android] Fix analysis issues

Author: SynSzakala

packages/image_picker/image_picker_android/CHANGELOG.md

@@ -1,6 +1,7 @@
-## NEXT
+## 0.8.5+6
 
 * Updates minimum Flutter version to 3.0.
+* Fixes names of picked files to match original filenames where possible.
 
 ## 0.8.5+5
 

packages/image_picker/image_picker_android/android/src/main/java/io/flutter/plugins/imagepicker/FileUtils.java

@@ -25,55 +25,60 @@
 
 import android.content.ContentResolver;
 import android.content.Context;
+import android.database.Cursor;
 import android.net.Uri;
+import android.provider.MediaStore;
 import android.webkit.MimeTypeMap;
+import io.flutter.Log;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.UUID;
 
 class FileUtils {
-
+  /**
+   * Copies the file from the given content URI to a temporary directory, retaining the original
+   * file name if possible.
+   *
+   * <p>Each file is placed in its own directory to avoid conflicts according to the following
+   * scheme: {cacheDir}/{randomUuid}/{fileName}
+   *
+   * <p>If the original file name is unknown, a predefined "image_picker" filename is used and the
+   * file extension is deduced from the mime type (with fallback to ".jpg" in case of failure).
+   */
   String getPathFromUri(final Context context, final Uri uri) {
-    File file = null;
-    InputStream inputStream = null;
-    OutputStream outputStream = null;
-    boolean success = false;
-    try {
-      String extension = getImageExtension(context, uri);
-      inputStream = context.getContentResolver().openInputStream(uri);
-      file = File.createTempFile("image_picker", extension, context.getCacheDir());
-      file.deleteOnExit();
-      outputStream = new FileOutputStream(file);
-      if (inputStream != null) {
-        copy(inputStream, outputStream);
-        success = true;
+    try (InputStream inputStream = context.getContentResolver().openInputStream(uri)) {
+      String uuid = UUID.randomUUID().toString();
+      File targetDirectory = new File(context.getCacheDir(), uuid);
+      targetDirectory.mkdir();
+      // TODO(SynSzakala) according to the docs, `deleteOnExit` does not work reliably on Android; we should preferably
+      //  just clear the picked files after the app startup.
+      targetDirectory.deleteOnExit();
+      String fileName = getImageName(context, uri);
+      if (fileName == null) {
+        Log.w("FileUtils", "Cannot get file name for " + uri);
+        fileName = "image_picker" + getImageExtension(context, uri);
       }
-    } catch (IOException ignored) {
-    } finally {
-      try {
-        if (inputStream != null) inputStream.close();
-      } catch (IOException ignored) {
-      }
-      try {
-        if (outputStream != null) outputStream.close();
-      } catch (IOException ignored) {
-        // If closing the output stream fails, we cannot be sure that the
-        // target file was written in full. Flushing the stream merely moves
-        // the bytes into the OS, not necessarily to the file.
-        success = false;
+      File file = new File(targetDirectory, fileName);
+      try (OutputStream outputStream = new FileOutputStream(file)) {
+        copy(inputStream, outputStream);
+        return file.getPath();
       }
+    } catch (IOException e) {
+      // If closing the output stream fails, we cannot be sure that the
+      // target file was written in full. Flushing the stream merely moves
+      // the bytes into the OS, not necessarily to the file.
+      return null;
     }
-    return success ? file.getPath() : null;
   }
 
   /** @return extension of image with dot, or default .jpg if it none. */
   private static String getImageExtension(Context context, Uri uriImage) {
-    String extension = null;
+    String extension;
 
     try {
-      String imagePath = uriImage.getPath();
       if (uriImage.getScheme().equals(ContentResolver.SCHEME_CONTENT)) {
         final MimeTypeMap mime = MimeTypeMap.getSingleton();
         extension = mime.getExtensionFromMimeType(context.getContentResolver().getType(uriImage));
@@ -94,6 +99,20 @@ private static String getImageExtension(Context context, Uri uriImage) {
     return "." + extension;
   }
 
+  /** @return name of the image provided by ContentResolver; this may be null. */
+  private static String getImageName(Context context, Uri uriImage) {
+    try (Cursor cursor = queryImageName(context, uriImage)) {
+      if (cursor == null || !cursor.moveToFirst() || cursor.getColumnCount() < 1) return null;
+      return cursor.getString(0);
+    }
+  }
+
+  private static Cursor queryImageName(Context context, Uri uriImage) {
+    return context
+        .getContentResolver()
+        .query(uriImage, new String[] {MediaStore.MediaColumns.DISPLAY_NAME}, null, null, null);
+  }
+
   private static void copy(InputStream in, OutputStream out) throws IOException {
     final byte[] buffer = new byte[4 * 1024];
     int bytesRead;

packages/image_picker/image_picker_android/android/src/test/java/io/flutter/plugins/imagepicker/FileUtilTest.java

@@ -8,8 +8,15 @@
 import static org.junit.Assert.assertTrue;
 import static org.robolectric.Shadows.shadowOf;
 
+import android.content.ContentProvider;
+import android.content.ContentValues;
 import android.content.Context;
+import android.database.Cursor;
+import android.database.MatrixCursor;
 import android.net.Uri;
+import android.provider.MediaStore;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.test.core.app.ApplicationProvider;
 import java.io.BufferedInputStream;
 import java.io.ByteArrayInputStream;
@@ -19,6 +26,7 @@
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.shadows.ShadowContentResolver;
 
@@ -63,4 +71,62 @@ public void FileUtil_getImageExtension() throws IOException {
     String path = fileUtils.getPathFromUri(context, uri);
     assertTrue(path.endsWith(".jpg"));
   }
+
+  @Test
+  public void FileUtil_getImageName() throws IOException {
+    Uri uri = Uri.parse("content://dummy/dummy.png");
+    Robolectric.buildContentProvider(MockContentProvider.class).create("dummy");
+    shadowContentResolver.registerInputStream(
+        uri, new ByteArrayInputStream("imageStream".getBytes(UTF_8)));
+    String path = fileUtils.getPathFromUri(context, uri);
+    assertTrue(path.endsWith("dummy.png"));
+  }
+
+  private static class MockContentProvider extends ContentProvider {
+
+    @Override
+    public boolean onCreate() {
+      return true;
+    }
+
+    @Nullable
+    @Override
+    public Cursor query(
+        @NonNull Uri uri,
+        @Nullable String[] projection,
+        @Nullable String selection,
+        @Nullable String[] selectionArgs,
+        @Nullable String sortOrder) {
+      MatrixCursor cursor = new MatrixCursor(new String[] {MediaStore.MediaColumns.DISPLAY_NAME});
+      cursor.addRow(new Object[] {"dummy.png"});
+      return cursor;
+    }
+
+    @Nullable
+    @Override
+    public String getType(@NonNull Uri uri) {
+      return "image/png";
+    }
+
+    @Nullable
+    @Override
+    public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {
+      return null;
+    }
+
+    @Override
+    public int delete(
+        @NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {
+      return 0;
+    }
+
+    @Override
+    public int update(
+        @NonNull Uri uri,
+        @Nullable ContentValues values,
+        @Nullable String selection,
+        @Nullable String[] selectionArgs) {
+      return 0;
+    }
+  }
 }

packages/image_picker/image_picker_android/example/android/app/build.gradle

@@ -63,5 +63,7 @@ dependencies {
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test:runner:1.2.0'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+    implementation project(':image_picker_android')
+    implementation project(':espresso')
     api 'androidx.test:core:1.4.0'
 }

packages/image_picker/image_picker_android/example/android/app/src/androidTest/java/io/flutter/plugins/imagepickerexample/ImagePickerPickTest.java

@@ -0,0 +1,43 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.imagepickerexample;
+
+import static androidx.test.espresso.flutter.EspressoFlutter.onFlutterWidget;
+import static androidx.test.espresso.flutter.action.FlutterActions.click;
+import static androidx.test.espresso.flutter.assertion.FlutterAssertions.matches;
+import static androidx.test.espresso.flutter.matcher.FlutterMatchers.withText;
+import static androidx.test.espresso.flutter.matcher.FlutterMatchers.withValueKey;
+import static androidx.test.espresso.intent.Intents.intended;
+import static androidx.test.espresso.intent.Intents.intending;
+import static androidx.test.espresso.intent.matcher.IntentMatchers.hasAction;
+
+import android.app.Activity;
+import android.app.Instrumentation;
+import android.content.Intent;
+import android.net.Uri;
+import androidx.test.espresso.intent.rule.IntentsTestRule;
+import org.junit.Ignore;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TestRule;
+
+public class ImagePickerPickTest {
+
+  @Rule public TestRule rule = new IntentsTestRule<>(DriverExtensionActivity.class);
+
+  @Test
+  @Ignore("Doesn't run in Firebase Test Lab: https://github.com/flutter/flutter/issues/94748")
+  public void imageIsPickedWithOriginalName() {
+    Instrumentation.ActivityResult result =
+        new Instrumentation.ActivityResult(
+            Activity.RESULT_OK, new Intent().setData(Uri.parse("content://dummy/dummy.png")));
+    intending(hasAction(Intent.ACTION_GET_CONTENT)).respondWith(result);
+    onFlutterWidget(withValueKey("image_picker_example_from_gallery")).perform(click());
+    onFlutterWidget(withText("PICK")).perform(click());
+    intended(hasAction(Intent.ACTION_GET_CONTENT));
+    onFlutterWidget(withValueKey("image_picker_example_picked_image_name"))
+        .check(matches(withText("dummy.png")));
+  }
+}

packages/image_picker/image_picker_android/example/android/app/src/debug/AndroidManifest.xml

@@ -13,5 +13,17 @@
             android:hardwareAccelerated="true"
             android:windowSoftInputMode="adjustResize">
         </activity>
+        <activity
+            android:name=".DriverExtensionActivity"
+            android:launchMode="singleTop"
+            android:theme="@android:style/Theme.Black.NoTitleBar"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+        </activity>
+        <provider
+            android:authorities="dummy"
+            android:name=".DummyContentProvider"
+            android:exported="true"/>
     </application>
 </manifest>

packages/image_picker/image_picker_android/example/android/app/src/main/java/io/flutter/plugins/imagepickerexample/DriverExtensionActivity.java

@@ -0,0 +1,16 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.imagepickerexample;
+
+import androidx.annotation.NonNull;
+import io.flutter.embedding.android.FlutterActivity;
+
+public class DriverExtensionActivity extends FlutterActivity {
+  @NonNull
+  @Override
+  public String getDartEntrypointFunctionName() {
+    return "appMain";
+  }
+}

packages/image_picker/image_picker_android/example/android/app/src/main/java/io/flutter/plugins/imagepickerexample/DummyContentProvider.java

@@ -0,0 +1,68 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.imagepickerexample;
+
+import android.content.ContentProvider;
+import android.content.ContentValues;
+import android.content.res.AssetFileDescriptor;
+import android.database.Cursor;
+import android.database.MatrixCursor;
+import android.net.Uri;
+import android.provider.MediaStore;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+public class DummyContentProvider extends ContentProvider {
+  @Override
+  public boolean onCreate() {
+    return true;
+  }
+
+  @Nullable
+  @Override
+  public AssetFileDescriptor openAssetFile(@NonNull Uri uri, @NonNull String mode) {
+    return getContext().getResources().openRawResourceFd(R.raw.ic_launcher);
+  }
+
+  @Nullable
+  @Override
+  public Cursor query(
+      @NonNull Uri uri,
+      @Nullable String[] projection,
+      @Nullable String selection,
+      @Nullable String[] selectionArgs,
+      @Nullable String sortOrder) {
+    MatrixCursor cursor = new MatrixCursor(new String[] {MediaStore.MediaColumns.DISPLAY_NAME});
+    cursor.addRow(new Object[] {"dummy.png"});
+    return cursor;
+  }
+
+  @Nullable
+  @Override
+  public String getType(@NonNull Uri uri) {
+    return "image/png";
+  }
+
+  @Nullable
+  @Override
+  public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {
+    return null;
+  }
+
+  @Override
+  public int delete(
+      @NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {
+    return 0;
+  }
+
+  @Override
+  public int update(
+      @NonNull Uri uri,
+      @Nullable ContentValues values,
+      @Nullable String selection,
+      @Nullable String[] selectionArgs) {
+    return 0;
+  }
+}