How to set socket timeout in Java HTTP Client

Question

We want to migrate all our apache-httpclient-4.x code to java-http-client code to reduce dependencies. While migrating them, i ran into the following issue under java 11:

How to set the socket timeout in Java HTTP Client?

With apache-httpclient-4.x we can set the connection timeout and the socket timeout like this:

DefaultHttpClient httpClient = new DefaultHttpClient();
int timeout = 5; // seconds
HttpParams httpParams = httpClient.getParams();
httpParams.setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, timeout * 1000);
httpParams.setParameter(CoreConnectionPNames.SO_TIMEOUT, timeout * 1000);

With java-http-client i can only set the connection timeout like this:

HttpClient httpClient = HttpClient.newBuilder()
                                  .connectTimeout(Duration.ofSeconds(5))
                                  .build()

But i found no way to set the socket timeout. Is there any way or an open issue to support that in the future?

Answer 1

We want to migrate all our apache-httpclient-4.x code to java-http-client code to reduce dependencies. While migrating them, i ran into the following issue under java 11:

How to set the socket timeout in Java HTTP Client?

With apache-httpclient-4.x we can set the connection timeout and the socket timeout like this:

DefaultHttpClient httpClient = new DefaultHttpClient();
int timeout = 5; // seconds
HttpParams httpParams = httpClient.getParams();
httpParams.setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, timeout * 1000);
httpParams.setParameter(CoreConnectionPNames.SO_TIMEOUT, timeout * 1000);

With java-http-client i can only set the connection timeout like this:

HttpClient httpClient = HttpClient.newBuilder()
                                  .connectTimeout(Duration.ofSeconds(5))
                                  .build()

But i found no way to set the socket timeout. Is there any way or an open issue to support that in the future?

Answer 2

There doesn't seem to be a way to specify a timeout on the flow of packets (socket timeout) on the Java Http Client.

I found an enhancement request on OpenJDK which seems to cover this possibility - https://bugs.openjdk.org/browse/JDK-8258397

Content from the link

The HttpClient lets you set a connection timeout (HttpClient.Builder) and a request timeout (HttpRequest.Builder). However the request timeout will be cancelled as soon as the response headers have been read. There is currently no timeout covering the reception of the body.

A possibility for the caller is to make use of the CompletableFuture API (get/join will accept a timeout, or CF::orTimeout can be called). IIRC - in that case, it will still be the responsibility of the caller to cancel the request. We might want to reexamine and possibility change that. The disadvantage here is that some of our BodyHandlers (ofPublisher, ofInputStream) will return immediately - so the CF API won't help in this case. This might be a good thing (or not).

Another possibility could be to add a body timeout on HttpRequest.Builder. This would then cover all cases - but do we really want to timeout in the case of ofInputStream or ofPublisher if the caller doesn't read the body fast enough?