notice when app engine java components aren't installed

src/main/java/com/google/cloud/tools/appengine/cloudsdk/AppEngineComponentsNotInstalledException.java

@@ -0,0 +1,11 @@
+package com.google.cloud.tools.appengine.cloudsdk;
+
+import com.google.cloud.tools.appengine.api.AppEngineException;
+
+public class AppEngineComponentsNotInstalledException extends AppEngineException {
+
+  AppEngineComponentsNotInstalledException(String message) {
+    super(message);
+  }
+
+}

src/main/java/com/google/cloud/tools/appengine/cloudsdk/CloudSdk.java

@@ -18,6 +18,7 @@
 
 import com.google.cloud.tools.appengine.api.AppEngineException;
 import com.google.cloud.tools.appengine.cloudsdk.internal.args.GcloudArgs;
+import com.google.cloud.tools.appengine.cloudsdk.internal.process.AccumulatingLineListener;
 import com.google.cloud.tools.appengine.cloudsdk.internal.process.DefaultProcessRunner;
 import com.google.cloud.tools.appengine.cloudsdk.internal.process.ProcessRunner;
 import com.google.cloud.tools.appengine.cloudsdk.internal.process.ProcessRunnerException;
@@ -70,22 +71,25 @@ public class CloudSdk {
   @Nullable
   private final File appCommandCredentialFile;
   private final String appCommandOutputFormat;
-  private final WaitingProcessOutputLineListener runDevAppServerWaitListener;
+  private final WaitingProcessOutputLineListener outputLineListener;
+  private final AccumulatingLineListener stdOutput;
 
   private CloudSdk(Path sdkPath,
                    String appCommandMetricsEnvironment,
                    String appCommandMetricsEnvironmentVersion,
                    @Nullable File appCommandCredentialFile,
                    String appCommandOutputFormat,
                    ProcessRunner processRunner,
-                   WaitingProcessOutputLineListener runDevAppServerWaitListener) {
+                   WaitingProcessOutputLineListener outputLineListener,
+                   AccumulatingLineListener stdOutput) {
     this.sdkPath = sdkPath;
     this.appCommandMetricsEnvironment = appCommandMetricsEnvironment;
     this.appCommandMetricsEnvironmentVersion = appCommandMetricsEnvironmentVersion;
     this.appCommandCredentialFile = appCommandCredentialFile;
     this.appCommandOutputFormat = appCommandOutputFormat;
     this.processRunner = processRunner;
-    this.runDevAppServerWaitListener = runDevAppServerWaitListener;
+    this.outputLineListener = outputLineListener;
+    this.stdOutput = stdOutput;
 
     // Populate jar locations.
     // TODO(joaomartins): Consider case where SDK doesn't contain these jars. Only App Engine
@@ -100,15 +104,14 @@ private CloudSdk(Path sdkPath,
   /**
    * Uses the process runner to execute the gcloud app command with the provided arguments.
    *
-   * @param args The arguments to pass to "gcloud app" command.
+   * @param args the arguments to pass to "gcloud app" command
    */
   public void runAppCommand(List<String> args) throws ProcessRunnerException {
     List<String> command = new ArrayList<>();
     command.add(getGCloudPath().toString());
     command.add("app");
     command.addAll(args);
 
-    command.add("--quiet");
     command.addAll(GcloudArgs.get("format", appCommandOutputFormat));
 
     Map<String, String> environment = Maps.newHashMap();
@@ -125,6 +128,31 @@ public void runAppCommand(List<String> args) throws ProcessRunnerException {
     logCommand(command);
     processRunner.setEnvironment(environment);
     processRunner.run(command.toArray(new String[command.size()]));
+    processRunner.run(command.toArray(new String[command.size()]));
+  }
+
+  /**
+   * @return true iff the specified component is installed in the local environment
+   */
+  public boolean isComponentInstalled(String id) throws ProcessRunnerException {
+    List<String> command = new ArrayList<>();
+    command.add(getGCloudPath().toString());
+    command.add("components");
+    command.add("list");
+    command.add("--format=json");
+    command.add("--filter=id:" + id);
+
+    if (stdOutput == null) {
+      throw new IllegalStateException("won't be able to read output");
+    }
+
+    stdOutput.clear();
+    processRunner.run(command.toArray(new String[command.size()]));
+
+    String json = stdOutput.getOutput(); 
+
+    // todo: parse the JSON
+    return json.contains("\"name\": \"Installed\"");
   }
 
   /**
@@ -149,8 +177,8 @@ public void runDevAppServerCommand(List<String> args) throws ProcessRunnerExcept
     processRunner.run(command.toArray(new String[command.size()]));
 
     // wait for start if configured
-    if (runDevAppServerWaitListener != null) {
-      runDevAppServerWaitListener.await();
+    if (outputLineListener != null) {
+      outputLineListener.await();
     }
   }
 
@@ -233,7 +261,7 @@ public Path getJarPath(String jarName) {
   /**
    * Checks whether the configured Cloud SDK Path is valid.
    *
-   * @throws AppEngineException when there is a validation error.
+   * @throws AppEngineException when there is a validation error
    */
   public void validate() throws AppEngineException {
     if (sdkPath == null) {
@@ -262,11 +290,20 @@ public void validate() throws AppEngineException {
           "Validation Error: Java Tools jar location '"
               + JAR_LOCATIONS.get(JAVA_TOOLS_JAR) + "' is not a file.");
     }
+    try {
+      if (!isComponentInstalled("app-engine-java")) {
+        throw new AppEngineComponentsNotInstalledException(
+            "Validation Error: App Engine Java component not installed");
+      }
+    } catch (ProcessRunnerException ex) {
+      throw new AppEngineException(
+          "Could not determine whether App Engine Java component is installed", ex);
+    }
   }
 
   @VisibleForTesting
   WaitingProcessOutputLineListener getRunDevAppServerWaitListener() {
-    return runDevAppServerWaitListener;
+    return outputLineListener;
   }
 
   public static class Builder {
@@ -415,10 +452,14 @@ public CloudSdk build() {
 
       // Verify there aren't listeners if subprocess inherits output.
       // If output is inherited, then listeners won't receive anything.
+      AccumulatingLineListener stdOut = null;
       if (inheritProcessOutput
           && (stdOutLineListeners.size() > 0 || stdErrLineListeners.size() > 0)) {
         throw new AppEngineException("You cannot specify subprocess output inheritance and"
             + " output listeners.");
+      } else {
+        stdOut = new AccumulatingLineListener();
+        stdOutLineListeners.add(stdOut);
       }
 
       // Construct process runner.
@@ -445,7 +486,7 @@ public CloudSdk build() {
 
       return new CloudSdk(sdkPath, appCommandMetricsEnvironment,
           appCommandMetricsEnvironmentVersion, appCommandCredentialFile, appCommandOutputFormat,
-          processRunner, runDevAppServerWaitListener);
+          processRunner, runDevAppServerWaitListener, stdOut);
     }
 
     /**
@@ -528,4 +569,5 @@ public int compare(CloudSdkResolver o1, CloudSdkResolver o2) {
     }
 
   }
+
 }

src/main/java/com/google/cloud/tools/appengine/cloudsdk/PathResolver.java

@@ -31,6 +31,7 @@ public class PathResolver implements CloudSdkResolver {
    *
    * @return Path to Google Cloud SDK or null
    */
+  @Override
   public Path getCloudSdkPath() {
     List<String> possiblePaths = new ArrayList<>();
 

src/main/java/com/google/cloud/tools/appengine/cloudsdk/internal/process/AccumulatingLineListener.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * 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.google.cloud.tools.appengine.cloudsdk.internal.process;
+
+import com.google.cloud.tools.appengine.cloudsdk.process.ProcessOutputLineListener;
+
+public class AccumulatingLineListener implements ProcessOutputLineListener {
+
+  private StringBuilder output = new StringBuilder();
+
+  @Override
+  public void onOutputLine(String line) {
+    output.append(line + "\n");
+  }
+
+  // todo: maybe this should be a standard part of ProcessRunner API instead?
+  public String getOutput() {
+    return output.toString(); 
+  }
+
+  public void clear() {
+    output = new StringBuilder();
+  }
+
+}

src/main/java/com/google/cloud/tools/appengine/cloudsdk/internal/process/DefaultProcessRunner.java

@@ -85,8 +85,9 @@ public DefaultProcessRunner(boolean async,
    * <p>If any output listeners were configured, output will go to them only. Otherwise, process
    * output will be redirected to the caller via inheritIO.
    *
-   * @param command The shell command to execute
+   * @param command the shell command to execute
    */
+  @Override
   public void run(String[] command) throws ProcessRunnerException {
     try {
       // Configure process builder.
@@ -135,13 +136,15 @@ public void run(String[] command) throws ProcessRunnerException {
   /**
    * Environment variables to append to the current system environment variables.
    */
+  @Override
   public void setEnvironment(Map<String, String> environment) {
     this.environment = environment;
   }
 
   private void handleStdOut(final Process process) {
     final Scanner stdOut = new Scanner(process.getInputStream(), Charsets.UTF_8.name());
     Thread stdOutThread = new Thread("standard-out") {
+      @Override
       public void run() {
         while (stdOut.hasNextLine() && !Thread.interrupted()) {
           String line = stdOut.nextLine();
@@ -159,6 +162,7 @@ public void run() {
   private void handleErrOut(final Process process) {
     final Scanner stdErr = new Scanner(process.getErrorStream(), Charsets.UTF_8.name());
     Thread stdErrThread = new Thread("standard-err") {
+      @Override
       public void run() {
         while (stdErr.hasNextLine() && !Thread.interrupted()) {
           String line = stdErr.nextLine();

src/test/java/com/google/cloud/tools/appengine/cloudsdk/CloudSdkEnvironmentTest.java

@@ -0,0 +1,40 @@
+package com.google.cloud.tools.appengine.cloudsdk;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.nio.file.Files;
+
+import org.junit.Test;
+
+import com.google.cloud.tools.appengine.cloudsdk.internal.process.ProcessRunnerException;
+
+/**
+ * Integration tests for {@link CloudSdk} that require an installed CloudSdk instance. 
+ */
+public class CloudSdkEnvironmentTest {
+
+  private CloudSdk sdk = new CloudSdk.Builder().build();
+
+  @Test
+  public void testGetSdkPath() {
+    assertTrue(Files.exists(sdk.getSdkPath()));
+  }
+
+  @Test
+  public void testIsComponentInstalled_true() throws ProcessRunnerException {
+    assertTrue(sdk.isComponentInstalled("app-engine-java"));
+  }
+
+  @Test
+  public void testIsComponentInstalled_False() throws ProcessRunnerException {
+    assertFalse(sdk.isComponentInstalled("no-such-component"));
+  }
+
+  @Test
+  public void testIsComponentInstalled_sequential() throws ProcessRunnerException {
+    assertTrue(sdk.isComponentInstalled("app-engine-java"));
+    assertFalse(sdk.isComponentInstalled("no-such-component"));
+  }
+
+}

src/test/java/com/google/cloud/tools/appengine/cloudsdk/CloudSdkTest.java

@@ -5,9 +5,8 @@
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.when;
 
-import com.google.cloud.tools.appengine.cloudsdk.CloudSdk.Builder;
-
 import com.google.cloud.tools.appengine.api.AppEngineException;
+import com.google.cloud.tools.appengine.cloudsdk.CloudSdk.Builder;
 import com.google.cloud.tools.appengine.cloudsdk.process.ProcessOutputLineListener;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -75,7 +74,7 @@ public void testNewCloudSdk_outListener() {
     CloudSdk sdk = builder.build();
 
     assertNotNull(sdk.getRunDevAppServerWaitListener());
-    assertEquals(2, builder.getStdOutLineListeners().size());
+    assertEquals(3, builder.getStdOutLineListeners().size());
     assertEquals(1, builder.getStdErrLineListeners().size());
     assertEquals(1, builder.getExitListeners().size());
   }
@@ -86,7 +85,7 @@ public void testNewCloudSdk_errListener() {
     CloudSdk sdk = builder.build();
 
     assertNotNull(sdk.getRunDevAppServerWaitListener());
-    assertEquals(1, builder.getStdOutLineListeners().size());
+    assertEquals(2, builder.getStdOutLineListeners().size());
     assertEquals(2, builder.getStdErrLineListeners().size());
     assertEquals(1, builder.getExitListeners().size());
   }