add smee-client example

Author: maxandersen

examples/smee.java

@@ -0,0 +1,185 @@
+//usr/bin/env jbang "$0" "$@" ; exit $?
+//DEPS info.picocli:picocli:4.2.0
+//DEPS org.jboss.resteasy:resteasy-client:4.4.1.Final
+//DEPS com.fasterxml.jackson.core:jackson-databind:2.2.3
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.apache.http.HttpRequest;
+import org.apache.http.client.methods.CloseableHttpResponse;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.StringEntity;
+import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.jboss.resteasy.client.jaxrs.ResteasyClientBuilder;
+import org.jboss.resteasy.client.jaxrs.engines.ApacheHttpClient43Engine;
+import org.jboss.resteasy.spi.ResteasyConfiguration;
+import picocli.CommandLine;
+import picocli.CommandLine.Command;
+import picocli.CommandLine.Parameters;
+
+import javax.ws.rs.HttpMethod;
+import javax.ws.rs.client.*;
+import javax.ws.rs.core.Configuration;
+import javax.ws.rs.core.Request;
+import javax.ws.rs.core.UriBuilder;
+import javax.ws.rs.sse.InboundSseEvent;
+import javax.ws.rs.sse.SseEventSource;
+import java.io.IOException;
+import java.net.*;
+import java.util.concurrent.Callable;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Logger;
+
+import static picocli.CommandLine.*;
+
+/**
+ * A pure java implementation of smee-client.
+ */
+@Command(name = "smee", mixinStandardHelpOptions = true, version = "smee 0.1",
+        description = "smee made with jbang", showDefaultValues = true)
+class smee implements Callable<Integer> {
+
+    private static final Logger log;
+
+    static {
+        System.setProperty("java.util.logging.SimpleFormatter.format",
+                "%5$s %n");
+        log = Logger.getLogger(smee.class.getName());
+    }
+    @Option(names = {"-u","--url"}, description = "URL of the webhook proxy service\n  Default: Fetch new from https://smee.io/new")
+    private String url;
+
+    @Option(names={"-t", "--target"},
+            description = "Full URL (including protocol and path) of the target service the events will forwarded to\n  Default: http://127.0.0.1:PORT/PATH")
+    private String target;
+
+    @Option(names={"-p","--port"}, defaultValue = "${PORT:-3000}", description = "Local HTTP server port")
+    int port;
+
+    @Option(names={"-P", "--path"}, defaultValue = "/", description = "URL path to post proxied requests to")
+    String path;
+
+    public static void main(String... args) {
+        int exitCode = new CommandLine(new smee()).execute(args);
+        System.exit(exitCode);
+    }
+
+    @Override
+    public Integer call() throws Exception { // your business logic goes here...
+
+        if(target==null) {
+            target = String.format("http://127.0.0.1:%s%s", port, path);
+        }
+
+        if(url==null) {
+            url = createChannel();
+        }
+
+        URI uri = new URI(url);
+
+        Client client = ClientBuilder.newBuilder()
+                                     .build();
+                                     //.register(HTTPLoggingFilter.class);
+
+        final var events = SseEventSource.target(client.target(uri))
+                                          // Reconnect immediately
+                                         .reconnectingEvery(0, TimeUnit.MILLISECONDS).build();
+
+        events.register(this::onMessage, this::onError);
+
+        log.info("Forwarding " + url + " to " + target);
+        events.open();
+
+        if(events.isOpen()) {
+            log.info("Connected " + url);
+        }
+
+        while(true) {
+            Thread.sleep(50000);
+        }
+
+        //return 0;
+    }
+
+    private void onError(Throwable error) {
+        log.severe(error.getMessage());
+    }
+
+    private void onMessage(InboundSseEvent event) {
+        if("ping".equals(event.getName()) || "ready".equals(event.getName())) {
+            return;
+        }
+        ObjectMapper mapper = new ObjectMapper();
+        try {
+            ObjectNode data = (ObjectNode) mapper.readTree(event.readData());
+
+            var urib = UriBuilder.fromUri(this.target);
+
+            if(data.has("query")) {
+                urib.replaceQuery(URLEncoder.encode(data.get("query").asText(), "UTF-8"));
+                data.remove("query");
+            }
+
+            try(CloseableHttpClient client = HttpClientBuilder.create().disableCookieManagement().build()) {
+
+                var request = new HttpPost(urib.build());
+
+                if(data.has("body")) {
+                    request.setEntity(new StringEntity(data.get("body").asText()));
+                    data.remove("body");
+                }
+
+                data.fieldNames().forEachRemaining(s ->
+                {
+                    if(!s.equalsIgnoreCase("content-length")) {
+                    request.setHeader(s, data.get(s).asText());
+                }});
+
+
+                CloseableHttpResponse response = client.execute(request);
+
+                if(response.getStatusLine().getStatusCode()!=200) {
+                    log.severe(response.getStatusLine().toString());
+                } else {
+                    log.info(request.getMethod() + " " + request.getURI() + " - " + response.getStatusLine().getStatusCode());
+                }
+            }
+
+        } catch (IOException e) {
+            log.warning("Could not parse event data: " + e.getMessage());
+            e.printStackTrace();
+        } catch (RuntimeException re) {
+            log.warning("Could not parse event data: " + re.getMessage());
+            re.printStackTrace();
+        }
+
+    }
+
+    private String createChannel() throws IOException {
+        HttpURLConnection con = (HttpURLConnection)(new URL( "https://smee.io/new" ).openConnection());
+        con.setInstanceFollowRedirects( false );
+        con.connect();
+        return con.getHeaderField( "Location" );
+    }
+
+    static public class HTTPLoggingFilter implements ClientRequestFilter, ClientResponseFilter {
+
+        private static final Logger logger = Logger.getLogger(HTTPLoggingFilter.class.getName());
+
+        @Override
+        public void filter(ClientRequestContext requestContext) throws IOException {
+            logger.info("request:" + requestContext.getUri().toString());
+            logger.info("request:" + requestContext.getHeaders().toString());
+
+        }
+
+        @Override
+        public void filter(ClientRequestContext requestContext, ClientResponseContext responseContext) throws IOException {
+            //
+            // logger.info(responseContext.getUri().toString());
+            logger.info("response: " + responseContext.getHeaders().toString());
+        }
+    }
+}