Add HttpClientConfiguration to configuration and refactor HttpClient creation and usage (#2842)

* Add HttpClientConfiguration to `configuration`

* Refactor HTTP client handling to improve configuration management.

* Refactor HTTPClientInterceptor initialization and fix Transport dependency handling.

* Refactor `HttpClientConfiguration` handling and improve `Transport` initialization logic.

* Initialize `name` and set `appliedFlow` in HTTPClientInterceptor constructor.

* refactor(core): rename `hc` to `httpClient` for improved code readability and consistency

* Update annotation from `@MCAttribute` to `@MCChildElement` for `setWsdlHttpClientConfig`.

* add legacy setter

* fix tests

* Pass `HttpClientFactory` to `ResolverMap` and `HTTPSchemaResolver` constructors to improve dependency management.

* Refactor `HTTPClientInterceptor` initialization for improved `HttpClientConfiguration` handling.

* Simplify constructor dependencies by removing redundant `HttpClientFactory` parameter from `ResolverMap` and `HTTPSchemaResolver`.

* fix(core): correct `combine` argument order in `ResolverMap` for proper factory handling

* refactor(core): initialize `DefaultRouter` in tests and simplify `ResolverMap` constructor

* Move `name` and `appliedFlow` initialization from constructor to `init` method in `HTTPClientInterceptor`.

* Refactor `SOAPProxy` resolver initialization and add config update method in `HTTPClientInterceptor`.

* add default resolvermap

* fix tests

---------

Co-authored-by: Thomas Bayer <bayer@predic8.de>

Author: christiangoerdes

annot/src/main/java/com/predic8/membrane/annot/generator/kubernetes/model/Schema.java

@@ -1,3 +1,17 @@
+/* Copyright 2026 predic8 GmbH, www.predic8.com
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License. */
+
 package com.predic8.membrane.annot.generator.kubernetes.model;
 
 import com.fasterxml.jackson.databind.node.ObjectNode;

core/src/main/java/com/predic8/membrane/core/cli/RouterCLI.java

@@ -221,11 +221,12 @@ private static Router initRouterByYAML(String location) throws Exception {
 
         var grammar = new GrammarAutoGenerated();
         var reg = new BeanRegistryImplementation(grammar);
+
         router.setRegistry(reg);
         reg.register("router", router);
 
         getConfigDefinition(reg.parseYamlBeanDefinitions(router.getResolverMap().resolve(location), grammar))
-                .ifPresent(beanDefinition -> router.applyConfiguration((Configuration) reg.resolve(beanDefinition.getName())));
+                .ifPresent(configBd -> router.applyConfiguration((Configuration) reg.resolve(configBd.getName())));
 
         reg.finishStaticConfiguration();
         reg.start();

core/src/main/java/com/predic8/membrane/core/interceptor/HTTPClientInterceptor.java

@@ -45,33 +45,42 @@ public class HTTPClientInterceptor extends AbstractInterceptor {
     // null => inherit from HttpClientConfiguration unless explicitly set here
     private Boolean failOverOn5XX;
 
-    private HttpClientConfiguration httpClientConfig = new HttpClientConfiguration();
+    private HttpClientConfiguration httpClientConfig;
 
-    private HttpClient hc;
+    private HttpClient httpClient;
 
-    public HTTPClientInterceptor() {
-        name = "http client";
-        setAppliedFlow(REQUEST_FLOW);
+    public HTTPClientInterceptor() {}
+
+    public HTTPClientInterceptor(HttpClient httpClient) {
+        this.httpClient = httpClient;
     }
 
     @Override
     public void init() {
+        name = "http client";
+        setAppliedFlow(REQUEST_FLOW);
+
         super.init();
 
+        if (httpClientConfig == null) httpClientConfig = router.getHttpClientConfig();
+
         // Overwrite httpClientConfiguration with local value
         if (failOverOn5XX != null) {
             httpClientConfig.getRetryHandler().setFailOverOn5XX(failOverOn5XX);
         }
 
-        hc = router.getHttpClientFactory().createClient(httpClientConfig);
-        hc.setStreamPumpStats(getRouter().getStatistics().getStreamPumpStats());
+        if (httpClient == null) {
+            httpClient = router.getHttpClientFactory().createClient(httpClientConfig);
+        }
+
+        httpClient.setStreamPumpStats(getRouter().getStatistics().getStreamPumpStats());
     }
 
     @Override
     public Outcome handleRequest(Exchange exc) {
         try {
             applyTargetModifications(exc);
-            hc.call(exc);
+            httpClient.call(exc);
             return RETURN;
         } catch (ConnectException e) {
             String msg = "Target %s is not reachable.".formatted(getDestination(exc));
@@ -131,6 +140,13 @@ public Outcome handleRequest(Exchange exc) {
         }
     }
 
+    // Used to update the httpClientConfig in tests
+    public void updateHttpClientConfig(HttpClientConfiguration httpClientConfig) {
+        this.httpClient = null;
+        this.httpClientConfig = httpClientConfig;
+        init();
+    }
+
     /**
      * Manipulates the target URL according to the target (change of method, URL expression)
      *

core/src/main/java/com/predic8/membrane/core/interceptor/jwt/Jwks.java

@@ -135,8 +135,7 @@ public String getJwk(Router router, ObjectMapper mapper) throws IOException {
             ResolverMap rm = router.getResolverMap();
 
             if (httpClientConfig != null) {
-                HTTPSchemaResolver httpSR = new HTTPSchemaResolver(router.getHttpClientFactory());
-                httpSR.setHttpClientConfig(httpClientConfig);
+                HTTPSchemaResolver httpSR = new HTTPSchemaResolver(router.getHttpClientFactory().createClient(httpClientConfig));
 
                 rm = rm.clone();
                 rm.addSchemaResolver(httpSR);

core/src/main/java/com/predic8/membrane/core/proxies/SOAPProxy.java

@@ -78,10 +78,8 @@ public SOAPProxy() {
     public void init() {
         resolverMap = router.getResolverMap();
         if (httpClientConfig != null) {
-            HTTPSchemaResolver httpSR = new HTTPSchemaResolver(router.getHttpClientFactory());
-            httpSR.setHttpClientConfig(httpClientConfig);
             resolverMap = resolverMap.clone();
-            resolverMap.addSchemaResolver(httpSR);
+            resolverMap.addSchemaResolver(new HTTPSchemaResolver(router.getHttpClientFactory().createClient(httpClientConfig)));
         }
         configureFromWSDL();
         super.init(); // Must be called last! Otherwise, SSL will not be configured!
@@ -293,7 +291,7 @@ public HttpClientConfiguration getWsdlHttpClientConfig() {
         return httpClientConfig;
     }
 
-    @MCAttribute
+    @MCChildElement
     public void setWsdlHttpClientConfig(HttpClientConfiguration httpClientConfig) {
         this.httpClientConfig = httpClientConfig;
     }

core/src/main/java/com/predic8/membrane/core/resolver/HTTPSchemaResolver.java

@@ -14,28 +14,32 @@
 
 package com.predic8.membrane.core.resolver;
 
-import com.google.common.collect.*;
-import com.predic8.membrane.annot.*;
-import com.predic8.membrane.core.exchange.*;
-import com.predic8.membrane.core.http.*;
-import com.predic8.membrane.core.transport.http.*;
-import com.predic8.membrane.core.transport.http.client.*;
-import com.predic8.membrane.core.util.*;
-import com.predic8.membrane.core.util.functionalInterfaces.*;
-
-import javax.annotation.*;
-import java.io.*;
-import java.net.*;
-import java.security.*;
-import java.util.*;
-import java.util.concurrent.*;
-
-import static com.predic8.membrane.annot.Constants.*;
-import static com.predic8.membrane.core.http.Header.*;
+import com.google.common.collect.Lists;
+import com.predic8.membrane.annot.MCElement;
+import com.predic8.membrane.core.exchange.Exchange;
+import com.predic8.membrane.core.http.Response;
+import com.predic8.membrane.core.transport.http.HttpClient;
+import com.predic8.membrane.core.transport.http.HttpClientFactory;
+import com.predic8.membrane.core.transport.http.client.HttpClientConfiguration;
+import com.predic8.membrane.core.util.URIFactory;
+import com.predic8.membrane.core.util.functionalInterfaces.ExceptionThrowingConsumer;
+
+import javax.annotation.Nullable;
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.net.URISyntaxException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+
+import static com.predic8.membrane.annot.Constants.PRODUCT_NAME;
+import static com.predic8.membrane.core.http.Header.USER_AGENT;
 import static com.predic8.membrane.core.http.Request.Builder;
-import static com.predic8.membrane.core.http.Request.*;
-import static java.lang.Thread.*;
-import static java.nio.charset.StandardCharsets.*;
+import static com.predic8.membrane.core.http.Request.METHOD_GET;
+import static java.lang.Thread.sleep;
+import static java.nio.charset.StandardCharsets.UTF_8;
 
 @MCElement(name = "httpSchemaResolver")
 public class HTTPSchemaResolver implements SchemaResolver {
@@ -48,9 +52,7 @@ public class HTTPSchemaResolver implements SchemaResolver {
 
     private static final byte[] NO_HASH = "NO_HASH".getBytes(UTF_8);
 
-    private HttpClientConfiguration httpClientConfig = new HttpClientConfiguration();
-
-    private HttpClient httpClient;
+    private final HttpClient httpClient;
     private final URIFactory uriFactory = new URIFactory(false);
 
     private final Runnable httpWatchJob = new Runnable() {
@@ -104,17 +106,8 @@ private Exchange createResolveExchange(String url) throws URISyntaxException {
         return new Builder().method(METHOD_GET).url(uriFactory, url).header(USER_AGENT, PRODUCT_NAME).buildExchange();
     }
 
-    public HTTPSchemaResolver(@Nullable HttpClientFactory httpClientFactory) {
-        this.httpClientFactory = httpClientFactory;
-    }
-
-    private synchronized HttpClient getHttpClient() {
-        if (httpClient == null) {
-            if (httpClientFactory == null)
-                httpClientFactory = new HttpClientFactory(null);
-            httpClient = httpClientFactory.createClient(httpClientConfig);
-        }
-        return httpClient;
+    public HTTPSchemaResolver(@Nullable HttpClient httpClient) {
+       this.httpClient = httpClient;
     }
 
     @Override
@@ -125,7 +118,7 @@ public List<String> getSchemas() {
     public InputStream resolve(String url) throws ResourceRetrievalException {
         try {
             var resolveExchange = createResolveExchange(url);
-            getHttpClient().call(resolveExchange);
+            httpClient.call(resolveExchange);
             Response response = resolveExchange.getResponse();
             response.readBody();
 
@@ -163,12 +156,4 @@ public long getTimestamp(String url) {
         return 0;
     }
 
-    public synchronized HttpClientConfiguration getHttpClientConfig() {
-        return httpClientConfig;
-    }
-
-    public synchronized void setHttpClientConfig(HttpClientConfiguration httpClientConfig) {
-        this.httpClientConfig = httpClientConfig;
-        httpClient = null;
-    }
 }

core/src/main/java/com/predic8/membrane/core/resolver/ResolverMap.java

@@ -20,6 +20,7 @@
 import com.predic8.membrane.core.kubernetes.client.*;
 import com.predic8.membrane.core.router.*;
 import com.predic8.membrane.core.transport.http.*;
+import com.predic8.membrane.core.transport.http.client.HttpClientConfiguration;
 import com.predic8.membrane.core.util.*;
 import com.predic8.membrane.core.util.functionalInterfaces.*;
 import com.predic8.xml.util.*;
@@ -54,17 +55,18 @@ public class ResolverMap implements Cloneable, Resolver {
     private String[] schemas;
     private SchemaResolver[] resolvers;
 
+
     public ResolverMap() {
-        this(null, null);
+        this(new HttpClientFactory(null).createClient(new HttpClientConfiguration()), null);
     }
 
-    public ResolverMap(HttpClientFactory httpClientFactory, KubernetesClientFactory kubernetesClientFactory) {
+    public ResolverMap(HttpClient httpClient, KubernetesClientFactory kubernetesClientFactory) {
         schemas = new String[10];
         resolvers = new SchemaResolver[10];
 
         // the default config
         addSchemaResolver(new ClasspathSchemaResolver());
-        addSchemaResolver(new HTTPSchemaResolver(httpClientFactory));
+        addSchemaResolver(new HTTPSchemaResolver(httpClient));
         addSchemaResolver(new KubernetesSchemaResolver(kubernetesClientFactory));
         addSchemaResolver(new FileSchemaResolver());
     }
@@ -104,7 +106,7 @@ private static String combineInternal(URIFactory factory,String... locations) {
             // lfold
             String[] l = new String[locations.length - 1];
             System.arraycopy(locations, 0, l, 0, locations.length - 1);
-            return combine(factory,combine(l), locations[locations.length - 1]);
+            return combine(factory,combine(factory,l), locations[locations.length - 1]);
         }
 
         return combineInternal2( factory, locations,locations[1], locations[0]);

core/src/main/java/com/predic8/membrane/core/router/Configuration.java

@@ -17,6 +17,7 @@
 import com.predic8.membrane.annot.*;
 import com.predic8.membrane.core.interceptor.administration.*;
 import com.predic8.membrane.core.proxies.*;
+import com.predic8.membrane.core.transport.http.client.HttpClientConfiguration;
 import com.predic8.membrane.core.util.*;
 
 /**
@@ -44,6 +45,8 @@ public class Configuration {
 
     private String baseLocation;
 
+    private HttpClientConfiguration httpClientConfig = new HttpClientConfiguration();
+
     /**
      * @param hotDeploy If true the hot deploy feature will be activated during init of the Router.
      * @description <p>Whether changes to the router's configuration file should automatically trigger a restart.
@@ -144,6 +147,20 @@ public URIFactory getUriFactory() {
         return uriFactory;
     }
 
+    /**
+     * @description A global &lt;httpClientConfig&gt;. This instance is used everywhere
+     * a HTTP Client is used. In every specific place, you should still be able to configure a local
+     * &lt;httpClientConfig&gt; (with higher precedence compared to this global instance).
+     */
+    @MCChildElement
+    public void setHttpClientConfig(HttpClientConfiguration httpClientConfig) {
+        this.httpClientConfig = httpClientConfig;
+    }
+
+    public HttpClientConfiguration getHttpClientConfig() {
+        return httpClientConfig;
+    }
+
     /**
      * @description Base location for the router's configuration file.
      * @param baseLocation The base directory path used to resolve relative file paths in configuration

core/src/main/java/com/predic8/membrane/core/router/DefaultMainComponents.java

@@ -46,8 +46,11 @@ public class DefaultMainComponents implements MainComponents {
 
     private final TimerManager timerManager = new TimerManager();
     private final HttpClientFactory httpClientFactory = new HttpClientFactory(timerManager);
+
+    private HttpClient httpClient = new HttpClient();
+
     private final KubernetesClientFactory kubernetesClientFactory = new KubernetesClientFactory(httpClientFactory);
-    private final ResolverMap resolverMap;
+    private ResolverMap resolverMap = new ResolverMap();
 
     private final FlowController flowController;
     private final RuleManager ruleManager;
@@ -58,22 +61,24 @@ public class DefaultMainComponents implements MainComponents {
     public DefaultMainComponents(DefaultRouter router) {
         log.debug("Creating new router.");
         this.router = router;
-        resolverMap = new ResolverMap(httpClientFactory, kubernetesClientFactory);
-        resolverMap.addRuleResolver(router);
         flowController = new FlowController(router);
         ruleManager= new RuleManager();
         ruleManager.setRouter(router);
     }
 
     public void init() {
+        httpClient = httpClientFactory.createClient(getHttpClientConfig());
+        resolverMap = new ResolverMap(httpClient, kubernetesClientFactory);
+        resolverMap.addRuleResolver(router);
+
         log.debug("Initializing.");
 
         if (registry == null) {
             registry = new BeanRegistryImplementation(null);
             registry.register("router", router);
         }
 
-        registry.registerIfAbsent(HttpClientConfiguration.class, HttpClientConfiguration::new);
+        registry.registerIfAbsent(HttpClientConfiguration.class, () -> router.getConfiguration().getHttpClientConfig());
         registry.registerIfAbsent(ExchangeStore.class, LimitedMemoryExchangeStore::new);
         registry.registerIfAbsent(DNSCache.class, DNSCache::new);
 
@@ -126,14 +131,6 @@ public void setTransport(Transport transport) {
         this.transport = transport;
     }
 
-    public HttpClientConfiguration getHttpClientConfig() {
-        return getResolverMap().getHTTPSchemaResolver().getHttpClientConfig();
-    }
-
-    public void setHttpClientConfig(HttpClientConfiguration httpClientConfig) {
-        getResolverMap().getHTTPSchemaResolver().setHttpClientConfig(httpClientConfig);
-    }
-
     @Override
     public DNSCache getDnsCache() {
         return getRegistry().getBean(DNSCache.class).orElseThrow(); // TODO
@@ -167,6 +164,15 @@ public HttpClientFactory getHttpClientFactory() {
         return httpClientFactory;
     }
 
+    @Override
+    public HttpClientConfiguration getHttpClientConfig() {
+        return router.getConfiguration().getHttpClientConfig();
+    }
+
+    public HttpClient getHttpClient() {
+        return httpClient;
+    }
+
     public FlowController getFlowController() {
         return flowController;
     }