Add http client pool configurations.

Author: inthirakumaaran

distribution/kernel/carbon-home/repository/resources/conf/default.json

@@ -257,6 +257,10 @@
   "keystore.datasource": "jdbc/SHARED_DB",
   "http_client.connection.timeout_in_milli_seconds": "180000",
   "http_client.socket.timeout_in_milli_seconds": "300000",
+  "http_client.pool.enabled": "false",
+  "http_client.pool.max_total_connections": "{{$ref{transport.https.properties.maxThreads}//2}}",
+  "http_client.pool.default_max_connections_per_route": "{{$ref{transport.https.properties.maxThreads}//2}}",
+  "http_client.pool.add_keep_alive_strategy": "true",
   "tracing.opentelemetry.ldap.enabled": false,
   "tracing.opentelemetry.ldap.scope_name": "wso2isldap"
 }

distribution/kernel/carbon-home/repository/resources/conf/templates/repository/conf/carbon.xml.j2

@@ -927,6 +927,14 @@
             <Socket>
                 <TimeoutInMilliSeconds>{{http_client.socket.timeout_in_milli_seconds}}</TimeoutInMilliSeconds>
             </Socket>
+            {% if http_client.pool.enabled is defined %}
+            <ConnectionPool>
+                <Enabled>{{http_client.pool.enabled}}</Enabled>
+                <MaxTotalConnections>{{http_client.pool.max_total_connections}}</MaxTotalConnections>
+                <DefaultMaxConnectionsPerRoute>{{http_client.pool.default_max_connections_per_route}}</DefaultMaxConnectionsPerRoute>
+                <AddKeepAliveStrategy>{{http_client.pool.add_keep_alive_strategy}}</AddKeepAliveStrategy>
+            </ConnectionPool>
+            {% endif %}
         </HttpClient>
 
     <!-- Configure to instrument operations using OpenTelemetry manual instrumentation -->