sample_updater: add non-streaming demo

SampleUpdater app was tested manually on a device.
There are unit tests for utility classes.

SampleUpdater app demonstrates how to use Android Update Engine to
apply A/B (seamless) update.
This CL contains demo of non-stream update using async update_engine,
which is accessed directly from an activity.
This app also shows logs from update_engine on the UI.
Instructions can be found in `README.md`.

- Create a UI with list of configs, current version, control buttons and a progress bar
- Add PayloadSpec and PayloadSpecs for working with update zip file
- Add UpdateConfig for working with json config files
- Add applying non-streaming update

Test: tested manually and unit tests for utilities
Change-Id: I05d4a46ad9cf8b334c9c60c7dd4da486dac0400a
Signed-off-by: Zhomart Mukhamejanov <zhomart@google.com>
diff --git a/sample_updater/tests/src/com/example/android/systemupdatersample/util/PayloadSpecsTest.java b/sample_updater/tests/src/com/example/android/systemupdatersample/util/PayloadSpecsTest.java
new file mode 100644
index 0000000..6f06ca3
--- /dev/null
+++ b/sample_updater/tests/src/com/example/android/systemupdatersample/util/PayloadSpecsTest.java
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.systemupdatersample.util;
+
+import static com.example.android.systemupdatersample.util.PackagePropertyFiles.PAYLOAD_BINARY_FILE_NAME;
+import static com.example.android.systemupdatersample.util.PackagePropertyFiles.PAYLOAD_PROPERTIES_FILE_NAME;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+
+import android.content.Context;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import com.example.android.systemupdatersample.PayloadSpec;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.junit.runner.RunWith;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.zip.CRC32;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+/**
+ * Tests if PayloadSpecs parses update package zip file correctly.
+ */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class PayloadSpecsTest {
+
+    private static final String PROPERTIES_CONTENTS = "k1=val1\nkey2=val2";
+    private static final String PAYLOAD_CONTENTS    = "hello\nworld";
+    private static final int PAYLOAD_SIZE           = PAYLOAD_CONTENTS.length();
+
+    private File mTestDir;
+
+    private Context mContext;
+
+    @Rule
+    public final ExpectedException thrown = ExpectedException.none();
+
+    @Before
+    public void setUp() {
+        mContext = InstrumentationRegistry.getTargetContext();
+
+        mTestDir = mContext.getFilesDir();
+    }
+
+    @Test
+    public void forNonStreaming_works() throws Exception {
+        File packageFile = createMockZipFile();
+        PayloadSpec spec = PayloadSpecs.forNonStreaming(packageFile);
+
+        assertEquals("correct url", "file://" + packageFile.getAbsolutePath(), spec.getUrl());
+        assertEquals("correct payload offset",
+                30 + PAYLOAD_BINARY_FILE_NAME.length(), spec.getOffset());
+        assertEquals("correct payload size", PAYLOAD_SIZE, spec.getSize());
+        assertArrayEquals("correct properties",
+                new String[]{"k1=val1", "key2=val2"}, spec.getProperties().toArray(new String[0]));
+    }
+
+    @Test
+    public void forNonStreaming_IOException() throws Exception {
+        thrown.expect(IOException.class);
+        PayloadSpecs.forNonStreaming(new File("/fake/news.zip"));
+    }
+
+    /**
+     * Creates package zip file that contains payload.bin and payload_properties.txt
+     */
+    private File createMockZipFile() throws IOException {
+        File testFile = new File(mTestDir, "test.zip");
+        try (ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(testFile))) {
+            // Add payload.bin entry.
+            ZipEntry entry = new ZipEntry(PAYLOAD_BINARY_FILE_NAME);
+            entry.setMethod(ZipEntry.STORED);
+            entry.setCompressedSize(PAYLOAD_SIZE);
+            entry.setSize(PAYLOAD_SIZE);
+            CRC32 crc = new CRC32();
+            crc.update(PAYLOAD_CONTENTS.getBytes(StandardCharsets.UTF_8));
+            entry.setCrc(crc.getValue());
+            zos.putNextEntry(entry);
+            zos.write(PAYLOAD_CONTENTS.getBytes(StandardCharsets.UTF_8));
+            zos.closeEntry();
+
+            // Add payload properties entry.
+            ZipEntry propertiesEntry = new ZipEntry(PAYLOAD_PROPERTIES_FILE_NAME);
+            zos.putNextEntry(propertiesEntry);
+            zos.write(PROPERTIES_CONTENTS.getBytes(StandardCharsets.UTF_8));
+            zos.closeEntry();
+        }
+        return testFile;
+    }
+
+}