Builds extra layer with contents of src/main/jib.

jib-gradle-plugin/src/integration-test/java/com/google/cloud/tools/jib/gradle/JibPluginIntegrationTest.java

@@ -113,7 +113,7 @@ public void testBuild_simple() throws IOException, InterruptedException {
     }
 
     Assert.assertEquals(
-        "Hello, world. An argument.\n",
+        "Hello, world. An argument.\nfoo\ncat\n",
         buildAndRun(simpleTestProject, "gcr.io/jib-integration-testing/simpleimage:gradle"));
   }
 
@@ -144,7 +144,7 @@ public void testDockerDaemon_empty() throws IOException, InterruptedException {
   @Test
   public void testDockerDaemon_simple() throws IOException, InterruptedException {
     Assert.assertEquals(
-        "Hello, world. An argument.\n",
+        "Hello, world. An argument.\nfoo\ncat\n",
         buildToDockerDaemonAndRun(
             simpleTestProject, "gcr.io/jib-integration-testing/simpleimage:gradle"));
   }

jib-gradle-plugin/src/integration-test/resources/projects/simple/src/main/java/com/test/HelloWorld.java

@@ -37,5 +37,12 @@ public static void main(String[] args) throws IOException, URISyntaxException {
     String world = new String(Files.readAllBytes(worldFile), StandardCharsets.UTF_8);
 
     System.out.println(greeting + ", " + world + ". " + (args.length > 0 ? args[0] : ""));
+
+    // Prints the contents of the extra files.
+    if (Files.exists(Paths.get("/foo"))) {
+      System.out.println(new String(Files.readAllBytes(Paths.get("/foo")), StandardCharsets.UTF_8));
+      System.out.println(
+          new String(Files.readAllBytes(Paths.get("/bar/cat")), StandardCharsets.UTF_8));
+    }
   }
 }

jib-gradle-plugin/src/integration-test/resources/projects/simple/src/main/jib/bar/cat

@@ -0,0 +1 @@
+cat

jib-gradle-plugin/src/integration-test/resources/projects/simple/src/main/jib/foo

@@ -0,0 +1 @@
+foo

jib-gradle-plugin/src/main/java/com/google/cloud/tools/jib/gradle/BuildDockerTask.java

@@ -19,6 +19,7 @@
 import com.google.cloud.tools.jib.builder.BuildConfiguration;
 import com.google.cloud.tools.jib.cache.CacheDirectoryCreationException;
 import com.google.cloud.tools.jib.configuration.CacheConfiguration;
+import com.google.cloud.tools.jib.configuration.LayerConfiguration;
 import com.google.cloud.tools.jib.docker.DockerClient;
 import com.google.cloud.tools.jib.frontend.BuildStepsExecutionException;
 import com.google.cloud.tools.jib.frontend.BuildStepsRunner;
@@ -31,6 +32,11 @@
 import com.google.cloud.tools.jib.registry.credentials.RegistryCredentials;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import javax.annotation.Nullable;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.GradleException;
@@ -72,7 +78,7 @@ public void setTargetImage(String targetImage) {
   }
 
   @TaskAction
-  public void buildDocker() throws InvalidImageReferenceException {
+  public void buildDocker() throws InvalidImageReferenceException, IOException {
     if (!new DockerClient().isDockerInstalled()) {
       throw new GradleException(HELPFUL_SUGGESTIONS.forDockerNotInstalled());
     }
@@ -107,6 +113,15 @@ public void buildDocker() throws InvalidImageReferenceException {
             .setJvmFlags(jibExtension.getJvmFlags())
             .setExposedPorts(ExposedPortsParser.parse(jibExtension.getExposedPorts()))
             .setAllowHttp(jibExtension.getAllowInsecureRegistries());
+    if (Files.exists(jibExtension.getExtraDirectory())) {
+      try (Stream<Path> extraFilesLayerDirectoryFiles =
+          Files.list(jibExtension.getExtraDirectory())) {
+        buildConfigurationBuilder.setExtraFilesLayerConfiguration(
+            LayerConfiguration.builder()
+                .addEntry(extraFilesLayerDirectoryFiles.collect(Collectors.toList()), "/")
+                .build());
+      }
+    }
     CacheConfiguration applicationLayersCacheConfiguration =
         CacheConfiguration.forPath(gradleProjectProperties.getCacheDirectory());
     buildConfigurationBuilder.setApplicationLayersCacheConfiguration(

jib-gradle-plugin/src/main/java/com/google/cloud/tools/jib/gradle/BuildImageTask.java

@@ -19,6 +19,7 @@
 import com.google.cloud.tools.jib.builder.BuildConfiguration;
 import com.google.cloud.tools.jib.cache.CacheDirectoryCreationException;
 import com.google.cloud.tools.jib.configuration.CacheConfiguration;
+import com.google.cloud.tools.jib.configuration.LayerConfiguration;
 import com.google.cloud.tools.jib.frontend.BuildStepsExecutionException;
 import com.google.cloud.tools.jib.frontend.BuildStepsRunner;
 import com.google.cloud.tools.jib.frontend.ExposedPortsParser;
@@ -30,6 +31,11 @@
 import com.google.cloud.tools.jib.registry.credentials.RegistryCredentials;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import javax.annotation.Nullable;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.GradleException;
@@ -71,7 +77,7 @@ public void setTargetImage(String targetImage) {
   }
 
   @TaskAction
-  public void buildImage() throws InvalidImageReferenceException {
+  public void buildImage() throws InvalidImageReferenceException, IOException {
     // Asserts required @Input parameters are not null.
     Preconditions.checkNotNull(jibExtension);
     GradleBuildLogger gradleBuildLogger = new GradleBuildLogger(getLogger());
@@ -114,6 +120,15 @@ public void buildImage() throws InvalidImageReferenceException {
             .setExposedPorts(ExposedPortsParser.parse(jibExtension.getExposedPorts()))
             .setTargetFormat(jibExtension.getFormat())
             .setAllowHttp(jibExtension.getAllowInsecureRegistries());
+    if (Files.exists(jibExtension.getExtraDirectory())) {
+      try (Stream<Path> extraFilesLayerDirectoryFiles =
+          Files.list(jibExtension.getExtraDirectory())) {
+        buildConfigurationBuilder.setExtraFilesLayerConfiguration(
+            LayerConfiguration.builder()
+                .addEntry(extraFilesLayerDirectoryFiles.collect(Collectors.toList()), "/")
+                .build());
+      }
+    }
     CacheConfiguration applicationLayersCacheConfiguration =
         CacheConfiguration.forPath(gradleProjectProperties.getCacheDirectory());
     buildConfigurationBuilder.setApplicationLayersCacheConfiguration(

jib-gradle-plugin/src/main/java/com/google/cloud/tools/jib/gradle/DockerContextTask.java

@@ -123,6 +123,7 @@ public void generateDockerContext() {
       // here.
       ExposedPortsParser.parse(jibExtension.getExposedPorts());
 
+      // TODO: Add support for extra files layer.
       new DockerContextGenerator(gradleProjectProperties.getSourceFilesConfiguration())
           .setBaseImage(jibExtension.getBaseImage())
           .setJvmFlags(jibExtension.getJvmFlags())

jib-gradle-plugin/src/main/java/com/google/cloud/tools/jib/gradle/JibExtension.java

@@ -21,6 +21,7 @@
 import com.google.cloud.tools.jib.image.json.BuildableManifestTemplate;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
+import java.nio.file.Path;
 import java.util.Collections;
 import java.util.List;
 import javax.annotation.Nullable;
@@ -66,11 +67,16 @@ public class JibExtension {
   private static final boolean DEFAULT_USE_ONLY_PROJECT_CACHE = false;
   private static final boolean DEFAULT_ALLOW_INSECURE_REGISTIRIES = false;
 
+  private static Path resolveDefaultExtraDirectory(Path projectDirectory) {
+    return projectDirectory.resolve("src").resolve("main").resolve("jib");
+  }
+
   private final ImageConfiguration from;
   private final ImageConfiguration to;
   private final ContainerParameters container;
   private final Property<Boolean> useOnlyProjectCache;
   private final Property<Boolean> allowInsecureRegistries;
+  private final Property<Path> extraDirectory;
 
   // TODO: Deprecated parameters; remove these 4
   private final ListProperty<String> jvmFlags;
@@ -92,13 +98,15 @@ public JibExtension(Project project) {
 
     useOnlyProjectCache = objectFactory.property(Boolean.class);
     allowInsecureRegistries = objectFactory.property(Boolean.class);
+    extraDirectory = objectFactory.property(Path.class);
 
     // Sets defaults.
     from.setImage(DEFAULT_FROM_IMAGE);
     jvmFlags.set(Collections.emptyList());
     args.set(Collections.emptyList());
     useOnlyProjectCache.set(DEFAULT_USE_ONLY_PROJECT_CACHE);
     allowInsecureRegistries.set(DEFAULT_ALLOW_INSECURE_REGISTIRIES);
+    extraDirectory.set(resolveDefaultExtraDirectory(project.getProjectDir().toPath()));
   }
 
   /**
@@ -176,6 +184,10 @@ public void setAllowInsecureRegistries(boolean allowInsecureRegistries) {
     this.allowInsecureRegistries.set(allowInsecureRegistries);
   }
 
+  public void setExtraDirectory(Path extraDirectory) {
+    this.extraDirectory.set(extraDirectory);
+  }
+
   @Internal
   String getBaseImage() {
     return Preconditions.checkNotNull(from.getImage());
@@ -251,4 +263,10 @@ boolean getUseOnlyProjectCache() {
   boolean getAllowInsecureRegistries() {
     return allowInsecureRegistries.get();
   }
+
+  @Input
+  @Optional
+  Path getExtraDirectory() {
+    return extraDirectory.get();
+  }
 }