H2GreetingServer.java
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* to you under the Apache License, Version 2.0 (the
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package org.apache.hc.core5.http2.examples;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.time.Instant;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import org.apache.hc.core5.http.ContentType;
import org.apache.hc.core5.http.EndpointDetails;
import org.apache.hc.core5.http.EntityDetails;
import org.apache.hc.core5.http.Header;
import org.apache.hc.core5.http.HttpException;
import org.apache.hc.core5.http.HttpHeaders;
import org.apache.hc.core5.http.HttpRequest;
import org.apache.hc.core5.http.HttpResponse;
import org.apache.hc.core5.http.Message;
import org.apache.hc.core5.http.NameValuePair;
import org.apache.hc.core5.http.URIScheme;
import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncServer;
import org.apache.hc.core5.http.message.BasicHttpResponse;
import org.apache.hc.core5.http.nio.AsyncEntityConsumer;
import org.apache.hc.core5.http.nio.AsyncRequestConsumer;
import org.apache.hc.core5.http.nio.AsyncServerRequestHandler;
import org.apache.hc.core5.http.nio.entity.AsyncEntityProducers;
import org.apache.hc.core5.http.nio.entity.DiscardingEntityConsumer;
import org.apache.hc.core5.http.nio.entity.StringAsyncEntityConsumer;
import org.apache.hc.core5.http.nio.support.AbstractServerExchangeHandler;
import org.apache.hc.core5.http.nio.support.BasicRequestConsumer;
import org.apache.hc.core5.http.nio.support.BasicResponseProducer;
import org.apache.hc.core5.http.protocol.HttpContext;
import org.apache.hc.core5.http.protocol.HttpCoreContext;
import org.apache.hc.core5.http2.HttpVersionPolicy;
import org.apache.hc.core5.http2.config.H2Config;
import org.apache.hc.core5.http2.impl.nio.bootstrap.H2ServerBootstrap;
import org.apache.hc.core5.io.CloseMode;
import org.apache.hc.core5.net.WWWFormCodec;
import org.apache.hc.core5.reactor.IOReactorConfig;
import org.apache.hc.core5.reactor.ListenerEndpoint;
import org.apache.hc.core5.util.TimeValue;
/**
* Example HTTP2 server that reads an entity body and responds back with a greeting.
*
* <pre>
* {@code
* $ curl -id name=bob localhost:8080
* HTTP/1.1 200 OK
* Date: Sat, 25 May 2019 03:44:49 GMT
* Server: Apache-HttpCore/5.0-beta8-SNAPSHOT (Java/1.8.0_202)
* Transfer-Encoding: chunked
* Content-Type: text/plain; charset=UTF-8
*
* Hello bob
* }</pre>
* <p>
* This examples uses a {@link AbstractServerExchangeHandler} for the basic request / response processing cycle.
*/
public class H2GreetingServer {
public static void main(final String[] args) throws ExecutionException, InterruptedException {
int port = 8080;
if (args.length >= 1) {
port = Integer.parseInt(args[0]);
}
final HttpAsyncServer server = H2ServerBootstrap.bootstrap()
.setH2Config(H2Config.DEFAULT)
.setIOReactorConfig(IOReactorConfig.DEFAULT)
.setVersionPolicy(HttpVersionPolicy.NEGOTIATE) // fallback to HTTP/1 as needed
// wildcard path matcher:
.register("*", CustomServerExchangeHandler::new)
.create();
Runtime.getRuntime().addShutdownHook(new Thread(() -> {
System.out.println("HTTP server shutting down");
server.close(CloseMode.GRACEFUL);
}));
server.start();
final Future<ListenerEndpoint> future = server.listen(new InetSocketAddress(port), URIScheme.HTTP);
final ListenerEndpoint listenerEndpoint = future.get();
System.out.println("Listening on " + listenerEndpoint.getAddress());
server.awaitShutdown(TimeValue.ofDays(Long.MAX_VALUE));
}
static class CustomServerExchangeHandler extends AbstractServerExchangeHandler<Message<HttpRequest, String>> {
@Override
protected AsyncRequestConsumer<Message<HttpRequest, String>> supplyConsumer(
final HttpRequest request,
final EntityDetails entityDetails,
final HttpContext context) {
// if there's no body don't try to parse entity:
AsyncEntityConsumer<String> entityConsumer = new DiscardingEntityConsumer<>();
if (entityDetails != null) {
entityConsumer = new StringAsyncEntityConsumer();
}
//noinspection unchecked
return new BasicRequestConsumer<>(entityConsumer);
}
@Override
protected void handle(final Message<HttpRequest, String> requestMessage,
final AsyncServerRequestHandler.ResponseTrigger responseTrigger,
final HttpContext localContext) throws HttpException, IOException {
final HttpCoreContext context = HttpCoreContext.cast(localContext);
final EndpointDetails endpoint = context.getEndpointDetails();
final HttpRequest req = requestMessage.getHead();
final String httpEntity = requestMessage.getBody();
// generic success response:
final HttpResponse resp = new BasicHttpResponse(200);
// recording the request
System.out.printf("[%s] %s %s %s%n", Instant.now(),
endpoint != null ? endpoint.getRemoteAddress() : null,
req.getMethod(),
req.getPath());
// Request without an entity - GET/HEAD/DELETE
if (httpEntity == null) {
responseTrigger.submitResponse(
new BasicResponseProducer(resp), context);
return;
}
// Request with an entity - POST/PUT
final Header cth = req.getHeader(HttpHeaders.CONTENT_TYPE);
final ContentType contentType = cth != null ? ContentType.parse(cth.getValue()) : null;
String name = "stranger";
if (contentType != null && contentType.isSameMimeType(ContentType.APPLICATION_FORM_URLENCODED)) {
// decoding the form entity into key/value pairs:
final List<NameValuePair> args = WWWFormCodec.parse(httpEntity, contentType.getCharset());
if (!args.isEmpty()) {
name = args.get(0).getValue();
}
}
// composing greeting:
final String greeting = String.format("Hello %s\n", name);
responseTrigger.submitResponse(
new BasicResponseProducer(resp, AsyncEntityProducers.create(greeting)), context);
}
}
}