Apache HttpClient 4.5: Connection Resets

Question

I am using httpClient version 4.5 to connect with our external vendor site. We do not need any connection pool or persistent connection, so I am using the BasicHttpClientConnectionManager to create the HttpClient.

This works fine for minimal number of requests, but if I test this for 1TPS for 1 hour, by the end of the test, we start seeing intermittent connection resets. (guessing request count > 100)

I/O exception (java.net.SocketException) caught when processing request to {s}->https://apiURL:443: Connection reset

Please find below the code snippet for making connection.

SSLContext sslContext = SSLContext.getInstance("TLS");
sslContext.init(kmf.getKeyManagers(), new X509TrustManager[] { new DefaultTrustManager() }, new SecureRandom());
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, new String[] { "TLSv1.2" }, null,SSLConnectionSocketFactory.getDefaultHostnameVerifier());
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("https", sslsf).register("http", new PlainConnectionSocketFactory()).build();

HttpClientConnectionManager connectionManager = new BasicHttpClientConnectionManager(socketFactoryRegistry);
HttpRequestRetryHandler retryHandler = new DefaultHttpRequestRetryHandler(1, false);

RequestConfig defaultRequestConfig = RequestConfig.custom().setSocketTimeout(Integer.parseInt(30000)).setConnectTimeout(Integer.parseInt(30000)).setConnectionRequestTimeout(30000).setCookieSpec(CookieSpecs.STANDARD).build();

CloseableHttpClient httpClient = HttpClients.custom().setConnectionManager(connectionManager).setDefaultRequestConfig(defaultRequestConfig).setRetryHandler(retryHandler).evictExpiredConnections().build();

HttpPost httpPost = new HttpPost(<endpoint>);
httpPost.setEntity(new UrlEncodedFormEntity(requestData));
httpResponse = httpClient.execute(httpPost);

I saw that fix for a similar issue reported is already available with version 4.5. (Ref: https://issues.apache.org/jira/browse/HTTPCLIENT-1655) provided by Oleg

If thats the case, not sure why I am still facing this issue. Could someone please help on this.

Thanks!

Answer 1

Hi Oleg,

I had been using the httpclient version 4.5.3 when I was still seeing the connection reset errors as posted above.

Later noticed that the fix for reset issue was committed to the version 4.5.1 (https://issues.apache.org/jira/browse/HTTPCLIENT-1655). So, just tried updating that particular version, ran a test and not seeing the connection reset errors any more. I had expected that this fix should also be available in the higher versions starting from 4.5.1. But, I guess its somehow missed out in the higher versions, have verified that its still an issue with version 4.5.3 for sure.

So, conclusion is that the connection reset error was fixed using httpclient 4.5.1 jar.

Thanks!