Add Vertx example (#195)

* Add Vertx example

Signed-off-by: Pierangelo Di Pilato <pierangelodipilato@gmail.com>

* Apply suggestion

Signed-off-by: Pierangelo Di Pilato <pierangelodipilato@gmail.com>

Author: pierDipi

examples/pom.xml

@@ -15,6 +15,7 @@
 
     <modules>
         <module>kafka</module>
+        <module>vertx</module>
     </modules>
 
 

examples/vertx/README.md

@@ -0,0 +1,19 @@
+# Vertx + CloudEvents sample
+
+## Build
+
+```shell
+mvn package
+```
+
+## Start HTTP Server
+
+```shell
+mvn exec:java -Dexec.mainClass="io.cloudevents.examples.vertx.SampleHTTPServer" -Dexec.args="8080"
+```
+
+## Start HTTP Client
+
+```shell
+mvn exec:java -Dexec.mainClass="io.cloudevents.examples.vertx.SampleHTTPClient" -Dexec.args="http://localhost:8080"
+```

examples/vertx/pom.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>cloudevents-examples</artifactId>
+        <groupId>io.cloudevents</groupId>
+        <version>2.0.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>cloudevents-vertx-example</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.cloudevents</groupId>
+            <artifactId>cloudevents-http-vertx</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.cloudevents</groupId>
+            <artifactId>cloudevents-json-jackson</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+    </dependencies>
+
+</project>

examples/vertx/src/main/java/io/cloudevents/examples/vertx/SampleHTTPClient.java

@@ -0,0 +1,71 @@
+package io.cloudevents.examples.vertx;
+
+import io.cloudevents.CloudEvent;
+import io.cloudevents.core.builder.CloudEventBuilder;
+import io.cloudevents.core.message.MessageReader;
+import io.cloudevents.http.vertx.VertxMessageFactory;
+import io.cloudevents.jackson.JsonFormat;
+import io.vertx.core.Vertx;
+import io.vertx.core.http.HttpClient;
+import io.vertx.core.http.HttpClientRequest;
+import java.net.URI;
+import java.util.UUID;
+
+public class SampleHTTPClient {
+
+    private static final int NUM_EVENTS = 20;
+
+    public static void main(String[] args) {
+
+        if (args.length != 1) {
+            System.err.println("Usage: SampleHTTPClient <event_sink>");
+            return;
+        }
+        final String eventSink = args[0];
+
+        final Vertx vertx = Vertx.vertx();
+        final HttpClient httpClient = vertx.createHttpClient();
+
+        // Create an event template to set basic CloudEvent attributes.
+        CloudEventBuilder eventTemplate = CloudEventBuilder.v1()
+            .withSource(URI.create("https://github.com/cloudevents/sdk-java/tree/master/examples/vertx"))
+            .withType("vertx.example");
+
+        // Send NUM_EVENTS events.
+        for (int i = 0; i < NUM_EVENTS; i++) {
+
+            // create HTTP request.
+            final HttpClientRequest request = httpClient.postAbs(eventSink)
+                .handler(response -> {
+
+                    // We need to read the event from the HTTP response we get, so create a MessageReader.
+                    VertxMessageFactory.createReader(response)
+                        // Covert the MessageReader to a CloudEvent.
+                        .map(MessageReader::toEvent)
+                        // Print out the event.
+                        .onSuccess(System.out::println)
+                        .onFailure(System.err::println);
+
+                })
+                .exceptionHandler(System.err::println);
+
+            String id = UUID.randomUUID().toString();
+            String data = "Event number " + i;
+
+            // Create the event starting from the template
+            final CloudEvent event = eventTemplate.newBuilder()
+                .withId(id)
+                .withData("text/plain", data.getBytes())
+                .build();
+
+            // We need to write the event to the request, so create a MessageWriter.
+            if (i % 2 == 0) {
+                VertxMessageFactory.createWriter(request)
+                    .writeBinary(event); // Use binary mode.
+            } else {
+                VertxMessageFactory.createWriter(request)
+                    .writeStructured(event, new JsonFormat()); // Use structured mode.
+            }
+        }
+    }
+}

examples/vertx/src/main/java/io/cloudevents/examples/vertx/SampleHTTPServer.java

@@ -0,0 +1,49 @@
+package io.cloudevents.examples.vertx;
+
+import io.cloudevents.core.message.MessageReader;
+import io.cloudevents.http.vertx.VertxMessageFactory;
+import io.vertx.core.Vertx;
+
+public class SampleHTTPServer {
+
+    public static void main(String[] args) {
+
+        if (args.length != 1) {
+            System.err.println("Usage: SampleHTTPServer <port>");
+            return;
+        }
+        final int port = Integer.parseInt(args[0]);
+
+        final Vertx vertx = Vertx.vertx();
+
+        // Create HTTP server.
+        vertx.createHttpServer()
+            .exceptionHandler(System.err::println)
+            .requestHandler(request -> {
+
+                // We need to read the event from the HTTP request we get, so create a MessageReader.
+                VertxMessageFactory.createReader(request)
+                    // Covert the MessageReader to a CloudEvent.
+                    .map(MessageReader::toEvent)
+                    .onSuccess(event -> {
+                        // Print out the event.
+                        System.out.println(event);
+
+                        // Write the same event as response in binary mode.
+                        VertxMessageFactory.createWriter(request.response()).writeBinary(event);
+                    })
+                    .onFailure(System.err::println);
+
+
+            })
+            .listen(port, server -> {
+                if (server.succeeded()) {
+                    System.out.println(
+                        "Server listening on port: " + server.result().actualPort()
+                    );
+                } else {
+                    System.err.println(server.cause().getMessage());
+                }
+            });
+    }
+}