Set mem_limit on linkeddatahub service

Set a custom `HttpRequestRetryHandler` lambda on the `ApacheConnector`

Author: namedgraph

docker-compose.yml

@@ -28,6 +28,7 @@ services:
   linkeddatahub:
     user: root # otherwise the ldh user does not have permissions to the mounted folder which is owner by root
     build: .
+    mem_limit: 2048m
     depends_on:
       - fuseki-admin
       - fuseki-end-user
@@ -117,7 +118,7 @@ services:
       - CLIENT_HOST=linkeddatahub
       - VARNISH_SIZE=1G
     entrypoint: /bin/sh -c "cp /etc/varnish/default.vcl.template /etc/varnish/default.vcl && sed -i 's|$${BACKEND_HOST}|'"$$BACKEND_HOST"'|g' /etc/varnish/default.vcl && sed -i 's|$${BACKEND_PORT}|'"$$BACKEND_PORT"'|g' /etc/varnish/default.vcl && sed -i 's|$${CLIENT_HOST}|'"$$CLIENT_HOST"'|g' /etc/varnish/default.vcl && /usr/local/bin/docker-varnish-entrypoint \"$$0\" \"$$@\""
-    command: [ "-t", "86400" ] # time to live
+    command: [ "-t", "86400", "-p", "timeout_idle=60s" ] # time to live
     volumes:
       - ./platform/varnish-backend.vcl.template:/etc/varnish/default.vcl.template:ro
   varnish-end-user:
@@ -132,7 +133,7 @@ services:
       - CLIENT_HOST=linkeddatahub
       - VARNISH_SIZE=1G
     entrypoint: /bin/sh -c "cp /etc/varnish/default.vcl.template /etc/varnish/default.vcl && sed -i 's|$${BACKEND_HOST}|'"$$BACKEND_HOST"'|g' /etc/varnish/default.vcl && sed -i 's|$${BACKEND_PORT}|'"$$BACKEND_PORT"'|g' /etc/varnish/default.vcl && sed -i 's|$${CLIENT_HOST}|'"$$CLIENT_HOST"'|g' /etc/varnish/default.vcl && /usr/local/bin/docker-varnish-entrypoint \"$$0\" \"$$@\""
-    command: [ "-t", "86400" ] # time to live
+    command: [ "-t", "86400", "-p", "timeout_idle=60s" ] # time to live
     volumes:
       - ./platform/varnish-backend.vcl.template:/etc/varnish/default.vcl.template:ro
   email-server:

src/main/java/com/atomgraph/linkeddatahub/Application.java

@@ -204,7 +204,9 @@
 import net.sf.saxon.s9api.XsltExecutable;
 import nu.xom.XPathException;
 import org.apache.http.HttpClientConnection;
+import org.apache.http.HttpHost;
 import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpRequestRetryHandler;
 import org.apache.http.config.Registry;
 import org.apache.http.config.RegistryBuilder;
 import org.apache.http.conn.ConnectionKeepAliveStrategy;
@@ -214,6 +216,7 @@
 import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
 import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
 import org.apache.http.protocol.HttpContext;
+import org.apache.http.protocol.HttpCoreContext;
 import org.apache.jena.query.DatasetFactory;
 import org.apache.jena.rdf.model.ModelFactory;
 import org.apache.jena.rdf.model.ResIterator;
@@ -230,7 +233,6 @@
 import org.glassfish.hk2.utilities.binding.AbstractBinder;
 import org.glassfish.jersey.client.ClientConfig;
 import org.glassfish.jersey.apache.connector.ApacheClientProperties;
-import org.glassfish.jersey.apache.connector.ApacheConnectionClosingStrategy;
 import org.glassfish.jersey.apache.connector.ApacheConnectorProvider;
 import org.glassfish.jersey.client.ClientProperties;
 import org.glassfish.jersey.client.RequestEntityProcessing;
@@ -1384,7 +1386,8 @@ public void releaseConnection(final HttpClientConnection managedConn, final Obje
         };
         if (maxConnPerRoute != null) conman.setDefaultMaxPerRoute(maxConnPerRoute);
         if (maxTotalConn != null) conman.setMaxTotal(maxTotalConn);
-
+        int maxRetryCount = 3;
+        
         ClientConfig config = new ClientConfig();
         config.connectorProvider(new ApacheConnectorProvider());
         config.register(MultiPartFeature.class);
@@ -1396,6 +1399,23 @@ public void releaseConnection(final HttpClientConnection managedConn, final Obje
         config.property(ClientProperties.FOLLOW_REDIRECTS, true);
         config.property(ClientProperties.REQUEST_ENTITY_PROCESSING, RequestEntityProcessing.BUFFERED); // https://stackoverflow.com/questions/42139436/jersey-client-throws-cannot-retry-request-with-a-non-repeatable-request-entity
         config.property(ApacheClientProperties.CONNECTION_MANAGER, conman);
+        config.property(ApacheClientProperties.RETRY_HANDLER, (HttpRequestRetryHandler) (IOException ex, int executionCount, HttpContext context) ->
+        {
+            // Extract the HTTP host from the context
+            HttpHost targetHost = (HttpHost) context.getAttribute(HttpCoreContext.HTTP_TARGET_HOST);
+            String serverName = targetHost != null ? targetHost.getHostName() : "Unknown";
+
+            if (executionCount > maxRetryCount) {
+                if (log.isWarnEnabled()) log.warn("Maximum tries reached for client HTTP pool to server '{}'", serverName);
+                return false;
+            }
+            if (ex instanceof org.apache.http.NoHttpResponseException) {
+                if (log.isWarnEnabled()) log.warn("No response from server '{}' on {} call", serverName, executionCount);
+                return true;
+            }
+            return false;
+        });
+        
         //config.property(ApacheClientProperties.CONNECTION_CLOSING_STRATEGY, new ApacheConnectionClosingStrategy.GracefulClosingStrategy());
         if (keepAliveStrategy != null) config.property(ApacheClientProperties.KEEPALIVE_STRATEGY, keepAliveStrategy);
 
@@ -1461,6 +1481,7 @@ public void releaseConnection(final HttpClientConnection managedConn, final Obje
             };
             if (maxConnPerRoute != null) conman.setDefaultMaxPerRoute(maxConnPerRoute);
             if (maxTotalConn != null) conman.setMaxTotal(maxTotalConn);
+            int maxRetryCount = 3;
 
             ClientConfig config = new ClientConfig();
             config.connectorProvider(new ApacheConnectorProvider());
@@ -1473,7 +1494,23 @@ public void releaseConnection(final HttpClientConnection managedConn, final Obje
             config.property(ClientProperties.FOLLOW_REDIRECTS, true);
             config.property(ClientProperties.REQUEST_ENTITY_PROCESSING, RequestEntityProcessing.BUFFERED); // https://stackoverflow.com/questions/42139436/jersey-client-throws-cannot-retry-request-with-a-non-repeatable-request-entity
             config.property(ApacheClientProperties.CONNECTION_MANAGER, conman);
+            config.property(ApacheClientProperties.RETRY_HANDLER, (HttpRequestRetryHandler) (IOException ex, int executionCount, HttpContext context) ->
+            {
+                // Extract the HTTP host from the context
+                HttpHost targetHost = (HttpHost) context.getAttribute(HttpCoreContext.HTTP_TARGET_HOST);
+                String serverName = targetHost != null ? targetHost.getHostName() : "Unknown";
 
+                if (executionCount > maxRetryCount) {
+                    if (log.isWarnEnabled()) log.warn("Maximum tries reached for client HTTP pool to server '{}'", serverName);
+                    return false;
+                }
+                if (ex instanceof org.apache.http.NoHttpResponseException) {
+                    if (log.isWarnEnabled()) log.warn("No response from server '{}' on {} call", serverName, executionCount);
+                    return true;
+                }
+                return false;
+            });
+        
             return ClientBuilder.newBuilder().
                 withConfig(config).
                 sslContext(ctx).