Develop Reference

HttpTimeout gracefully close connection

I am using java Apache HttpClient to request a resource (B) with a timeout of 10s. If timeout exceeds Broken pipe is seen at the other application server.
Because of which Nginx at application B is not caching the response. How to gracefully close the connection so that the other app server (B) does not encounter broken pipe exception.

If you're using new enough HttpClient can't you do something like this (I just found a snippet someone else had written ... but see below where I've added ###)
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("http://localhost:8081/test/resource"))
.header("Accept", "application/json")
.POST(HttpRequest.BodyPublishers.ofString("ping!"))
.build();
CompletableFuture<HttpResponse<String>> completableFuture =
client.sendAsync(request, HttpResponse.BodyHandlers.ofString());
completableFuture
.completeOnTimeout(DEFAULT_RESPONSE, 1, TimeUnit.SECONDS) // ### ADD THIS the HttpClientRequest actually continues but the future has timed out so the user of the client progresses ??
.thenApplyAsync(HttpResponse::headers)
.thenAcceptAsync(System.out::println);
HttpResponse<String> response = completableFuture.join();

Authenticate http call to GitHub APIs in java

I'm working on a project which requires to call GitHub APIs several times and I reached the limit of 60.
I read that with authentication you get 5000 as limit but I can't understand how I can authenticate my requests in my java program. I got my authentication token on Github and this is the way I'm building the request in java:
// create client
HttpClient client = HttpClient.newHttpClient();
// create request
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("https://api.github.com/repos/:owner/:repo/commits"))
.build();
what should I add to the request to authenticate it?
I tried adding the header authToken:myToken but it didn't work.

Solved:
Once I got the token on my GitHub profile > Settings > Developer Settings > Personal Access Tokens, I added the header `"Authorization: Bearer "myToken" " to the http request so the request becomes:
// create client
HttpClient client = HttpClient.newHttpClient();
// create request
HttpRequest request = HttpRequest.newBuilder().header("Authorization","Bearer <myToken>")
.uri(URI.create("https://api.github.com/repos/:owner/:repo/commits"))
.build();

You need to add Http request header Authorization to your request and the header should contain your token. So if your code is written on Java 11 or higher as it appears to be than you need to change your code to:
// create client
HttpClient client = HttpClient.newHttpClient();
// create request
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("https://api.github.com/repos/:owner/:repo/commits"))
.header("Authorization", "your-tocken")
.build();

Java application that monitors the file change on the server

I need to write a small program, that constantly checks if the JSON file on the server has been updated (by some other process) to report the change to the user of the program.
I'm interested in best/correct practice of doing it: how would I implement the idea of "listening" to the file-change?
So far, my idea is:
ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);
executor.scheduleAtFixedRate(getMessage, 0,1, TimeUnit.SECONDS);
where getMessage is the:
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("url/get_message"))
.build();
HttpResponse<String> response = client.send(request,
HttpResponse.BodyHandlers.ofString());
message = response.body();

Add Proxy to HttpRequest in java

I'm trying to understand how can I implement the use of a proxy for each request built like the following using Java API:
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
.version(HttpClient.Version.HTTP_2)
.uri(URI.createh("https://myurl"))
.timeout(Duration.ofMinutes(2))
.setHeader("User-Agent","Just an user agent")
.GET()
.build();
HttpResponse<String> response = client.send(request,
HttpResponse.BodyHandlers.ofString());
I'm seeing from the doc (https://docs.oracle.com/en/java/javase/11/docs/api/java.net.http/java/net/http/HttpClient.html#Asynchronous%20Example)
that is possible with Synchronous requests. My code is within a method and it will run with threads parallelly. So how is it possible to set a proxy with Asynchronous Requests? If it is not possible, what's the difference between them?

Solved, it's a bit unclear the doc about that but at the end, I was able to set the proxy when building the client:
HttpClient client = HttpClient.newBuilder().
proxy(ProxySelector.of(new InetSocketAddress("proxy",port))))
.build();
//The request code is identical to what I wrote above.
The method is newBuilder anyway and not Builder.

Slow responsetime from Amazon Ec2 instance

Im running Java/Spring application with a Angular6 frontend. Within the Spring backend I calling another API thru http. but its around 6x slower than expected to get at response...
Isolating the API-call I get:
Locally running the same setup (Spring, Tomcat 8.5) from my dev-machine: 10-12 sec
Locally thru Postman: 10-12 sec
locally thru cUrl: 10-12 sec
Using cUrl from the console on the AWS EC2 instance 10-12sec.
Calling as intended (Spring running in Tomcat) on the AWS EC2 instance: 60-75sec.
Tried to change the Native Spring http (ResponseEntity postForEntity) call to OkHttp with no change in the result. The Api request and response is a tiny Json-string but the APi is slow so response times around 10 sec is normal.
As it seems to be something wrong with the Tomcat or java on the EC2. Can it be some parameters that I missed? or what else can i try to isolate and solve the problem?
The amount of data sent and revived is trivial (sending ~350 bytes, receiving less than that)
Its just the call to the API that takes a long time.
logger.debug("CallApi start");
start = System.currentTimeMillis();
try {
ObjectMapper mapper = new ObjectMapper();
String s = mapper.writeValueAsString(apiCalcDTO.getInput());
OkHttpClient client = new OkHttpClient.Builder()
.connectTimeout(120, TimeUnit.SECONDS)
.writeTimeout(120, TimeUnit.SECONDS)
.readTimeout(120, TimeUnit.SECONDS)
.build();
MediaType mediaType = MediaType.parse("application/x-www-form-urlencoded");
RequestBody body = RequestBody.create(mediaType, body);
Request request = new Request.Builder()
.url("http://www.example.com/api/1.0/xxx")
.post(body)
.addHeader("Content-Type", "application/x-www-form-urlencoded")
.addHeader("cache-control", "no-cache")
.build();
Response response = client.newCall(request).execute();
elapsed = System.currentTimeMillis() - start;
logger.debug("CallApi time = " + elapsed);