Take a screenshot after every test

android/java/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxgl/testapp/BaseTest.java

@@ -3,6 +3,8 @@ package com.mapbox.mapboxgl.testapp;
 import android.support.test.InstrumentationRegistry;
 import android.test.ActivityInstrumentationTestCase2;
 
+import com.mapbox.mapboxgl.testapp.utils.ScreenshotUtil;
+
 import org.junit.Before;
 
 /**
@@ -17,6 +19,10 @@ public class BaseTest
         super(MainActivity.class);
     }
 
+    /*
+     * Get the activity before running every test
+     */
+
     @Before
     public void setUp() throws Exception {
         super.setUp();
@@ -24,4 +30,25 @@ public class BaseTest
         mActivity = getActivity();
     }
 
+    /*
+     * Take a screenshot after every test
+     */
+
+    @Override
+    protected void tearDown() throws Exception {
+        try {
+            // Screenshots should be taken on the UI thread
+            runTestOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    ScreenshotUtil.take(getActivity());
+                }
+            });
+        } catch (Throwable throwable) {
+            throwable.printStackTrace();
+        }
+
+        super.tearDown();
+    }
+
 }

android/java/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxgl/testapp/utils/ScreenshotUtil.java

@@ -0,0 +1,88 @@
+package com.mapbox.mapboxgl.testapp.utils;
+
+import android.app.Activity;
+import android.graphics.Bitmap;
+import android.os.Environment;
+import android.util.Log;
+import android.view.View;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.UUID;
+
+/**
+ * The built-in Fuzz Suite on AWS Device Farm takes screenshots after every test. However,
+ * this doesn't happen with Espresso unless we manually do it. This class fixes it.
+ */
+public class ScreenshotUtil {
+
+    private static final String LOG_TAG = ScreenshotUtil.class.getName();
+
+    // Where to store the files. This path is required by AWS Device Farm:
+    // http://docs.aws.amazon.com/devicefarm/latest/developerguide/test-types-android-instrumentation.html#test-types-android-instrumentation-screenshots
+    private static final String SCREENSHOT_FOLDER = "test-screenshots";
+
+    // Image type and quality
+    private static final String DEFAULT_IMAGE_EXTENSION = ".png";
+    private static final Bitmap.CompressFormat DEFAULT_IMAGE_FORMAT = Bitmap.CompressFormat.PNG;
+    private static final int DEFAULT_IMAGE_QUALITY = 100;
+
+    public static void take(Activity activity) {
+
+        // Check if storage is available
+        if (!isExternalStorageWritable()) {
+            Log.d(LOG_TAG, "External storage is not available.");
+            return;
+        }
+
+        // Get a bitmap from the activity root view. When the drawing cache is enabled,
+        // the next call to getDrawingCache() will draw the view in a bitmap.
+        View rootView = activity.getWindow().getDecorView().getRootView();
+        rootView.setDrawingCacheEnabled(true);
+        Bitmap bitmap = Bitmap.createBitmap(rootView.getDrawingCache());
+        rootView.setDrawingCacheEnabled(false);
+
+        // Save the bitmap in external storage
+        String uniqueAbsolutePath = getUniqueAbsolutePath();
+        File outputFile = new File(uniqueAbsolutePath);
+        OutputStream outputStream = null;
+        try {
+            outputStream = new FileOutputStream(outputFile);
+            bitmap.compress(DEFAULT_IMAGE_FORMAT, DEFAULT_IMAGE_QUALITY, outputStream);
+            outputStream.flush();
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            if (outputStream != null) {
+                try {
+                    outputStream.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+    }
+
+    /* Checks if external storage is available for read and write */
+    public static boolean isExternalStorageWritable() {
+        String state = Environment.getExternalStorageState();
+        if (Environment.MEDIA_MOUNTED.equals(state)) {
+            return true;
+        }
+        return false;
+    }
+
+    private static String getUniqueAbsolutePath() {
+        String externalPath = Environment.getExternalStorageDirectory().toString();
+        String filename = UUID.randomUUID().toString() + DEFAULT_IMAGE_EXTENSION;
+        String path = externalPath + File.separator + SCREENSHOT_FOLDER + File.separator + filename;
+        Log.d(LOG_TAG, "Screenshot path: " + path);
+        return path;
+    }
+
+}