updated config, simplified defaults for http client

Author: ibalosh

src/main/java/com/postmarkapp/postmark/client/HttpClient.java

@@ -3,7 +3,6 @@
 import org.apache.hc.client5.http.config.RequestConfig;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
 import org.apache.hc.client5.http.impl.classic.HttpClientBuilder;
-import org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManager;
 import org.apache.hc.core5.http.ClassicHttpRequest;
 import org.apache.hc.core5.http.ContentType;
 import org.apache.hc.core5.http.HttpEntity;
@@ -14,8 +13,6 @@
 import java.io.IOException;
 import java.util.Map;
 
-
-
 /**
  * Base HTTP client class solely responsible for making
  * client requests and returning simple HTTP response.
@@ -46,6 +43,8 @@ public HttpClient(Map<String,Object> headers, int connectTimeoutSeconds, int rea
         this.clientConfigBuilder = RequestConfig
                 .custom()
                 .setConnectTimeout(Timeout.ofSeconds(connectTimeoutSeconds))
+                .setConnectionRequestTimeout(Timeout.ofSeconds(connectTimeoutSeconds))
+                .setConnectionKeepAlive(Timeout.ofSeconds(connectTimeoutSeconds))
                 .setResponseTimeout(Timeout.ofSeconds(readTimeoutSeconds));
 
         this.client = buildClient();
@@ -158,7 +157,6 @@ private CloseableHttpClient buildClient() {
         return HttpClientBuilder
                 .create()
                 .setDefaultRequestConfig(clientConfigBuilder.build())
-                .setConnectionManager(new PoolingHttpClientConnectionManager())
                 .build();
     }