Remove support for GIF attachments on API < 24.

bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java

@@ -8,12 +8,12 @@ import android.provider.Settings;
 
 import java.io.File;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 
 import static android.content.Context.MODE_PRIVATE;
 import static android.os.Build.VERSION.SDK_INT;
+import static java.util.Arrays.asList;
 
 public class AndroidUtils {
 
@@ -26,7 +26,7 @@ public class AndroidUtils {
 	public static Collection<String> getSupportedArchitectures() {
 		List<String> abis = new ArrayList<>();
 		if (SDK_INT >= 21) {
-			abis.addAll(Arrays.asList(Build.SUPPORTED_ABIS));
+			abis.addAll(asList(Build.SUPPORTED_ABIS));
 		} else {
 			abis.add(Build.CPU_ABI);
 			if (Build.CPU_ABI2 != null) abis.add(Build.CPU_ABI2);
@@ -57,4 +57,15 @@ public class AndroidUtils {
 	public static File getReportDir(Context ctx) {
 		return ctx.getDir(STORED_REPORTS, MODE_PRIVATE);
 	}
+
+	/**
+	 * Returns an array of supported content types for image attachments.
+	 * GIFs can't be compressed on API < 24 so they're not supported.
+	 * <p>
+	 * TODO: Remove this restriction when large message support is added
+	 */
+	public static String[] getSupportedImageContentTypes() {
+		if (SDK_INT < 24) return new String[] {"image/jpeg", "image/png"};
+		else return new String[] {"image/jpeg", "image/png", "image/gif"};
+	}
 }

briar-android/src/androidTestOfficial/java/org/briarproject/briar/android/attachment/AttachmentCreationTaskTest.java

@@ -11,9 +11,11 @@ import java.util.logging.Logger;
 
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 
+import static android.os.Build.VERSION.SDK_INT;
 import static androidx.test.InstrumentationRegistry.getContext;
 import static androidx.test.core.app.ApplicationProvider.getApplicationContext;
 import static java.util.logging.Logger.getLogger;
+import static org.junit.Assume.assumeTrue;
 
 @RunWith(AndroidJUnit4.class)
 public class AttachmentCreationTaskTest {
@@ -30,30 +32,55 @@ public class AttachmentCreationTaskTest {
 			imageSizeCalculator, null, null, true);
 
 	@Test
-	public void testCompress() throws Exception {
+	public void testCompress100x100Png() throws Exception {
-		InputStream is = getAssetInputStream("animated.gif");
+		testCompress("red-100x100.png", "image/png");
-		task.compressImage(is, "image/gif");
+	}
 
-		is = getAssetInputStream("animated2.gif");
+	@Test
-		task.compressImage(is, "image/gif");
+	public void testCompress500x500Png() throws Exception {
+		testCompress("blue-500x500.png", "image/png");
+	}
 
-		is = getAssetInputStream("blue-500x500.png");
+	@Test
-		task.compressImage(is, "image/png");
+	public void testCompress1000x2000Png() throws Exception {
+		testCompress("green-1000x2000.png", "image/png");
+	}
 
-		is = getAssetInputStream("error_high.jpg");
+	@Test
-		task.compressImage(is, "image/jpeg");
+	public void testCompressVeryHighJpg() throws Exception {
+		testCompress("error_high.jpg", "image/jpeg");
+	}
 
-		is = getAssetInputStream("error_large.gif");
+	@Test
-		task.compressImage(is, "image/gif");
+	public void testCompressVeryWideJpg() throws Exception {
+		testCompress("error_wide.jpg", "image/jpeg");
+	}
 
-		is = getAssetInputStream("error_wide.jpg");
+	@Test
-		task.compressImage(is, "image/jpeg");
+	public void testCompressAnimatedGif1() throws Exception {
+		// TODO: Remove this assumption when we support large messages
+		assumeTrue(SDK_INT >= 24);
+		testCompress("animated.gif", "image/gif");
+	}
 
-		is = getAssetInputStream("green-1000x2000.png");
+	@Test
-		task.compressImage(is, "image/png");
+	public void testCompressAnimatedGif2() throws Exception {
+		// TODO: Remove this assumption when we support large messages
+		assumeTrue(SDK_INT >= 24);
+		testCompress("animated2.gif", "image/gif");
+	}
 
-		is = getAssetInputStream("red-100x100.png");
+	@Test
-		task.compressImage(is, "image/png");
+	public void testCompressVeryLargeGif() throws Exception {
+		// TODO: Remove this assumption when we support large messages
+		assumeTrue(SDK_INT >= 24);
+		testCompress("error_large.gif", "image/gif");
+	}
+
+	private void testCompress(String filename, String contentType)
+			throws Exception {
+		InputStream is = getAssetInputStream(filename);
+		task.compressImage(is, contentType);
 	}
 
 	@Test

briar-android/src/main/java/org/briarproject/briar/android/attachment/AttachmentCreationTask.java

@@ -26,14 +26,15 @@ import androidx.annotation.VisibleForTesting;
 
 import static android.graphics.Bitmap.CompressFormat.JPEG;
 import static android.graphics.BitmapFactory.decodeStream;
+import static java.util.Arrays.asList;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.AndroidUtils.getSupportedImageContentTypes;
 import static org.briarproject.bramble.util.IoUtils.tryToClose;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
-import static org.briarproject.briar.api.messaging.MessagingConstants.IMAGE_MIME_TYPES;
 import static org.briarproject.briar.api.messaging.MessagingConstants.MAX_IMAGE_SIZE;
 
 @NotNullByDefault
@@ -108,7 +109,7 @@ class AttachmentCreationTask {
 		long start = now();
 		String contentType = contentResolver.getType(uri);
 		if (contentType == null) throw new IOException("null content type");
-		if (!isValidMimeType(contentType)) {
+		if (!asList(getSupportedImageContentTypes()).contains(contentType)) {
 			String uriString = uri.toString();
 			throw new UnsupportedMimeTypeException("", contentType, uriString);
 		}
@@ -124,13 +125,6 @@ class AttachmentCreationTask {
 		return h;
 	}
 
-	private boolean isValidMimeType(String mimeType) {
-		for (String supportedType : IMAGE_MIME_TYPES) {
-			if (supportedType.equals(mimeType)) return true;
-		}
-		return false;
-	}
-
 	@VisibleForTesting
 	InputStream compressImage(InputStream is, String contentType)
 			throws IOException {

briar-android/src/main/java/org/briarproject/briar/android/view/TextAttachmentController.java

@@ -40,8 +40,8 @@ import static android.widget.Toast.LENGTH_LONG;
 import static androidx.core.content.ContextCompat.getColor;
 import static androidx.customview.view.AbsSavedState.EMPTY_STATE;
 import static androidx.lifecycle.Lifecycle.State.DESTROYED;
+import static org.briarproject.bramble.util.AndroidUtils.getSupportedImageContentTypes;
 import static org.briarproject.briar.android.util.UiUtils.resolveColorAttribute;
-import static org.briarproject.briar.api.messaging.MessagingConstants.IMAGE_MIME_TYPES;
 import static org.briarproject.briar.api.messaging.MessagingConstants.MAX_ATTACHMENTS_PER_MESSAGE;
 
 @UiThread
@@ -131,7 +131,8 @@ public class TextAttachmentController extends TextSendController
 				ACTION_OPEN_DOCUMENT : ACTION_GET_CONTENT);
 		intent.setType("image/*");
 		intent.addCategory(CATEGORY_OPENABLE);
-		if (SDK_INT >= 19) intent.putExtra(EXTRA_MIME_TYPES, IMAGE_MIME_TYPES);
+		if (SDK_INT >= 19)
+			intent.putExtra(EXTRA_MIME_TYPES, getSupportedImageContentTypes());
 		if (SDK_INT >= 18) intent.putExtra(EXTRA_ALLOW_MULTIPLE, true);
 		return intent;
 	}

briar-api/src/main/java/org/briarproject/briar/api/messaging/MessagingConstants.java

@@ -19,15 +19,6 @@ public interface MessagingConstants {
 	 */
 	int MAX_CONTENT_TYPE_BYTES = 50;
 
-	/**
-	 * The supported mime types for image attachments.
-	 */
-	String[] IMAGE_MIME_TYPES = {
-			"image/jpeg",
-			"image/png",
-			"image/gif",
-	};
-
 	/**
 	 * The maximum allowed size of image attachments.
 	 * TODO: Different limit for GIFs?