Created Prober subproject and setup basic ActionHandler and its unit tests (#133)

* Initial Commit.

* Deleted unfinished features. Added ActionHandler and its Unit Tests.

* Included prober subproject in settings.gradle

* Added Protocol Class and its Basic Unit Tests

* Added Changes Suggested by jianglai

* Fixed Gitignore to take out AutoValue generated code

* Removed AutoValue java files

* Added gitignore within prober

* Removed all generated java

* Final Changes in .gitignore

* Added Ssl and WebWhois Action Handlers and their unit tests in addition to the ProbingAction class

* Fixed build.gradle changes requested

* Removed Files irrelevant to current pull request

* Minor fixes to ActionHandler, as responded in comments, removed package-info, and updated settings.gradle

* Fully Updated ActionHandler (missing updated JavaDoc)

* Added changed Protocol and both Inbound and Outbound Markers

* Removed AutoVaue ignore clause from .gitignore

* removed unneccessary dependencies in build.gradle

* Fixed Javadoc and comments for ActionHandler

* Fixed comments and JavaDoc on other files

* EOL added

* Removed Unnecessary Files

* fixed .gradle files styles

* Merge remote-tracking branch 'upstream/master'

* Removed outbound message from ActionHandler's fields and renamed Marker Interfaces

* Fixed javadoc for Marker Interfaced

* Modified Comments on ActionHandler

* Removed LocalAddress from Protocol

* Fixed Travis Build Issues

prober/.gitignore

@@ -0,0 +1 @@
+out/

prober/build.gradle

@@ -0,0 +1,49 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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.
+
+apply plugin: 'java'
+
+createUberJar('deployJar', 'prober', 'google.registry.monitoring.blackbox.Prober')
+
+dependencies {
+    def deps = rootProject.dependencyMap
+
+    compile deps['com.google.auto.value:auto-value-annotations']
+    compile deps['com.google.dagger:dagger']
+    compile deps['com.google.flogger:flogger']
+    compile deps['com.google.guava:guava']
+    compile deps['io.netty:netty-buffer']
+    compile deps['io.netty:netty-codec-http']
+    compile deps['io.netty:netty-codec']
+    compile deps['io.netty:netty-common']
+    compile deps['io.netty:netty-handler']
+    compile deps['io.netty:netty-transport']
+    compile deps['javax.inject:javax.inject']
+
+    runtime deps['com.google.flogger:flogger-system-backend']
+    runtime deps['com.google.auto.value:auto-value']
+    runtime deps['io.netty:netty-tcnative-boringssl-static']
+
+    testCompile deps['com.google.truth:truth']
+    testCompile deps['junit:junit']
+    testCompile deps['org.mockito:mockito-core']
+    testCompile project(':third_party')
+
+    // Include auto-value in compile until nebula-lint understands
+    // annotationProcessor
+    annotationProcessor deps['com.google.auto.value:auto-value']
+    testAnnotationProcessor deps['com.google.auto.value:auto-value']
+    annotationProcessor deps['com.google.dagger:dagger-compiler']
+    testAnnotationProcessor deps['com.google.dagger:dagger-compiler']
+}

prober/src/main/java/google/registry/monitoring/blackbox/Protocol.java

@@ -0,0 +1,58 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.monitoring.blackbox;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import io.netty.channel.ChannelHandler;
+import javax.inject.Provider;
+
+/**
+ * {@link AutoValue} class that stores all unchanged variables necessary for type of connection
+ */
+@AutoValue
+public abstract class Protocol {
+
+  abstract String name();
+
+  public abstract int port();
+
+  /** The {@link ChannelHandler} providers to use for the protocol, in order. */
+  abstract ImmutableList<Provider<? extends ChannelHandler>> handlerProviders();
+
+  /** Boolean that notes if connection associated with Protocol is persistent.*/
+  abstract boolean persistentConnection();
+
+  public abstract Builder toBuilder();
+
+  public static Builder builder() {
+    return new AutoValue_Protocol.Builder();
+  }
+
+  @AutoValue.Builder
+  public static abstract class Builder {
+
+    public abstract Builder name(String value);
+
+    public abstract Builder port(int num);
+
+    public abstract Builder handlerProviders(ImmutableList<Provider<? extends ChannelHandler>> providers);
+
+    public abstract Builder persistentConnection(boolean value);
+
+    public abstract Protocol build();
+  }
+}
+

prober/src/main/java/google/registry/monitoring/blackbox/handlers/ActionHandler.java

@@ -0,0 +1,74 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.monitoring.blackbox.handlers;
+
+import com.google.common.flogger.FluentLogger;
+import google.registry.monitoring.blackbox.messages.InboundMessageType;
+import google.registry.monitoring.blackbox.messages.OutboundMessageType;
+import io.netty.channel.SimpleChannelInboundHandler;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelPromise;
+
+/**
+ *Superclass of all {@link ChannelHandler}s placed at end of channel pipeline
+ *
+ * <p> {@code ActionHandler} inherits from {@link SimpleChannelInboundHandler< InboundMessageType >}, as it should only be passed in
+ * messages that implement the {@link InboundMessageType} interface. </p>
+ *
+ * <p> The {@code ActionHandler} skeleton exists for a few main purposes. First, it returns a {@link ChannelPromise},
+ * which informs the {@link ProbingAction} in charge that a response has been read. Second, it stores the {@link OutboundMessageType}
+ * passed down the pipeline, so that subclasses can use that information for their own processes. Lastly, with any exception
+ * thrown, the connection is closed, and the ProbingAction governing this channel is informed of the error. Subclasses
+ * specify further work to be done for specific kinds of channel pipelines. </p>
+ */
+public abstract class ActionHandler extends SimpleChannelInboundHandler<InboundMessageType> {
+
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  protected ChannelPromise finished;
+
+  /** Takes in {@link OutboundMessageType} type and saves for subclasses. Then returns initialized {@link ChannelPromise}*/
+  public ChannelFuture getFuture() {
+    return finished;
+  }
+
+  /** Initializes new {@link ChannelPromise} */
+  @Override
+  public void handlerAdded(ChannelHandlerContext ctx) {
+    //Once handler is added to channel pipeline, initialize channel and future for this handler
+    finished = ctx.newPromise();
+  }
+
+  @Override
+  public void channelRead0(ChannelHandlerContext ctx, InboundMessageType inboundMessage) throws Exception {
+    //simply marks finished as success
+    finished.setSuccess();
+  }
+
+  /** Logs the channel and pipeline that caused error, closes channel, then informs {@link ProbingAction} listeners of error */
+  @Override
+  public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
+    logger.atSevere().withCause(cause).log(String.format(
+        "Attempted Action was unsuccessful with channel: %s, having pipeline: %s",
+        ctx.channel().toString(),
+        ctx.channel().pipeline().toString()));
+
+    finished.setFailure(cause);
+    ChannelFuture closedFuture = ctx.channel().close();
+    closedFuture.addListener(f -> logger.atInfo().log("Unsuccessful channel connection closed"));
+  }
+}
+

prober/src/main/java/google/registry/monitoring/blackbox/messages/InboundMessageType.java

@@ -0,0 +1,21 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.monitoring.blackbox.messages;
+
+/**
+ * Marker Interface that is implemented by all classes that serve as {@code inboundMessages} in channel pipeline
+ */
+public interface InboundMessageType {}
+

prober/src/main/java/google/registry/monitoring/blackbox/messages/OutboundMessageType.java

@@ -0,0 +1,21 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.monitoring.blackbox.messages;
+
+/**
+ * Marker Interface that is implemented by all classes that serve as {@code outboundMessages} in channel pipeline
+ */
+public interface OutboundMessageType {}
+

settings.gradle

@@ -28,6 +28,7 @@ if (pluginsUrl) {
 rootProject.name = 'nomulus'
 
 include 'core'
+include 'prober'
 include 'proxy'
 include 'third_party'
 include 'util'