dns resolver configurable from outside via WebserviceConfiguration (#30)

todvora · Mar 9, 2017 · 3af94ec · 3af94ec
1 parent c3efc97
commit 3af94ec
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Showing 7 changed files with 72 additions and 31 deletions.
diff --git a/src/main/java/cz/tomasdvorak/eet/client/dto/DnsResolver.java b/src/main/java/cz/tomasdvorak/eet/client/dto/DnsResolver.java
@@ -0,0 +1,20 @@
+package cz.tomasdvorak.eet.client.dto;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+/**
+ * Implement this interface if you want to use dns lookup different than default implementation based on {@link InetAddress}.
+ * You can for example use http://www.xbill.org/dnsjava/ implementation or any other custom logic.
+ */
+public interface DnsResolver {
+
+    /**
+     * Convert a domain name to IP address.
+     *
+     * @param hostname Pure hostname, without protocol or path. For example pg.eet.cz
+     * @return IP address as a String
+     * @throws UnknownHostException in case DNS lookup fails.
+     */
+    String getHostAddress(String hostname) throws UnknownHostException;
+}
diff --git a/src/main/java/cz/tomasdvorak/eet/client/dto/WebserviceConfiguration.java b/src/main/java/cz/tomasdvorak/eet/client/dto/WebserviceConfiguration.java
@@ -1,5 +1,7 @@
 package cz.tomasdvorak.eet.client.dto;
 
+import cz.tomasdvorak.eet.client.networking.InetAddressDnsResolver;
+
 /**
  * TODO: create builder for the configuration!
  */
@@ -15,6 +17,7 @@ public class WebserviceConfiguration {
     );
     private long receiveTimeout;
     private long dnsLookupTimeout;
+    private DnsResolver dnsResolver;
 
     /**
      * @param receiveTimeout receiving timeout of the Webservice call in millis
@@ -30,6 +33,7 @@ public WebserviceConfiguration(final long receiveTimeout) {
     public WebserviceConfiguration(final long receiveTimeout, final long dnsLookupTimeout) {
         this.receiveTimeout = receiveTimeout;
         this.dnsLookupTimeout = dnsLookupTimeout;
+        this.dnsResolver = new InetAddressDnsResolver();
     }
 
     public long getReceiveTimeout() {
@@ -39,4 +43,12 @@ public long getReceiveTimeout() {
     public long getDnsLookupTimeout() {
         return dnsLookupTimeout;
     }
+
+    public DnsResolver getDnsResolver() {
+        return dnsResolver;
+    }
+
+    public void setDnsResolver(final DnsResolver dnsResolver) {
+        this.dnsResolver = dnsResolver;
+    }
 }
diff --git a/...ak/eet/client/networking/DnsResolver.java → ...orak/eet/client/networking/DnsLookup.java b/...ak/eet/client/networking/DnsResolver.java → ...orak/eet/client/networking/DnsLookup.java
@@ -3,6 +3,6 @@
 import cz.tomasdvorak.eet.client.exceptions.DnsLookupFailedException;
 import cz.tomasdvorak.eet.client.exceptions.DnsTimeoutException;
 
-public interface DnsResolver {
+public interface DnsLookup {
     String resolveAddress(String url) throws DnsLookupFailedException, DnsTimeoutException;
 }
diff --git a/...nt/networking/DnsResolverWithTimeout.java → ...ient/networking/DnsLookupWithTimeout.java b/...nt/networking/DnsResolverWithTimeout.java → ...ient/networking/DnsLookupWithTimeout.java
@@ -1,32 +1,32 @@
 package cz.tomasdvorak.eet.client.networking;
 
+import cz.tomasdvorak.eet.client.dto.DnsResolver;
 import cz.tomasdvorak.eet.client.exceptions.DnsLookupFailedException;
 import cz.tomasdvorak.eet.client.exceptions.DnsTimeoutException;
-import cz.tomasdvorak.eet.client.security.SecureEETCommunication;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.net.InetAddress;
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.net.UnknownHostException;
 import java.util.concurrent.*;
 
-public class DnsResolverWithTimeout implements DnsResolver {
+public class DnsLookupWithTimeout implements DnsLookup {
 
-    private static final Logger logger = LogManager.getLogger(SecureEETCommunication.class);
+    private static final Logger logger = LogManager.getLogger(DnsLookupWithTimeout.class);
 
     private final long timeoutMillis;
+    private final DnsResolver dnsResolver;
 
-    public DnsResolverWithTimeout(long timeoutMillis) {
+    public DnsLookupWithTimeout(final DnsResolver dnsResolver, final long timeoutMillis) {
+        this.dnsResolver = dnsResolver;
         this.timeoutMillis = timeoutMillis;
     }
 
     @Override
     public String resolveAddress(final String url) throws DnsLookupFailedException, DnsTimeoutException {
-        final String host;
+        final String hostname;
         try {
-            host = new URL(url).getHost();
+            hostname = new URL(url).getHost();
         } catch (MalformedURLException e) {
             throw new DnsLookupFailedException(String.format("URL %s is malformed", url), e);
         }
@@ -36,28 +36,20 @@ public String resolveAddress(final String url) throws DnsLookupFailedException,
             Future<String> result = executor.submit(new Callable<String>() {
                 @Override
                 public String call() throws Exception {
-                    return doResolve(host);
+                    return dnsResolver.getHostAddress(hostname);
                 }
             });
             return result.get(timeoutMillis, TimeUnit.MILLISECONDS);
         } catch (InterruptedException e) {
-            logger.warn("Unexpected interrupton while resolving host " + host, e);
+            logger.warn("Unexpected interrupton while resolving hostname " + hostname, e);
             Thread.currentThread().interrupt();
-            throw new DnsLookupFailedException("Unexpected interruption while resolving host " + host, e);
+            throw new DnsLookupFailedException("Unexpected interruption while resolving hostname " + hostname, e);
         } catch (ExecutionException e) {
-            throw new DnsLookupFailedException("Failed resolving host " + host, e.getCause());
+            throw new DnsLookupFailedException("Failed resolving hostname " + hostname, e.getCause());
         } catch (TimeoutException e) {
-            throw new DnsTimeoutException(String.format("DNS Lookup for host %s timed out", host), e);
+            throw new DnsTimeoutException(String.format("DNS Lookup for host %s timed out", hostname), e);
         } finally {
             executor.shutdownNow();
         }
     }
-
-    /**
-     * Internal method to allow easier unit testing without dependency on internet connection
-     */
-    protected String doResolve(final String host) throws UnknownHostException {
-        InetAddress address = InetAddress.getByName(host);
-        return address.getHostAddress();
-    }
 }
diff --git a/src/main/java/cz/tomasdvorak/eet/client/networking/InetAddressDnsResolver.java b/src/main/java/cz/tomasdvorak/eet/client/networking/InetAddressDnsResolver.java
@@ -0,0 +1,15 @@
+package cz.tomasdvorak.eet.client.networking;
+
+import cz.tomasdvorak.eet.client.dto.DnsResolver;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+public class InetAddressDnsResolver implements DnsResolver {
+
+    @Override
+    public String getHostAddress(final String hostname) throws UnknownHostException {
+        InetAddress address = InetAddress.getByName(hostname);
+        return address.getHostAddress();
+    }
+}
diff --git a/src/main/java/cz/tomasdvorak/eet/client/security/SecureEETCommunication.java b/src/main/java/cz/tomasdvorak/eet/client/security/SecureEETCommunication.java
@@ -7,8 +7,8 @@
 
 import cz.tomasdvorak.eet.client.exceptions.DnsLookupFailedException;
 import cz.tomasdvorak.eet.client.exceptions.DnsTimeoutException;
-import cz.tomasdvorak.eet.client.networking.DnsResolver;
-import cz.tomasdvorak.eet.client.networking.DnsResolverWithTimeout;
+import cz.tomasdvorak.eet.client.networking.DnsLookup;
+import cz.tomasdvorak.eet.client.networking.DnsLookupWithTimeout;
 import org.apache.cxf.endpoint.Client;
 import org.apache.cxf.frontend.ClientProxy;
 import org.apache.cxf.jaxws.JaxWsProxyFactoryBean;
@@ -75,7 +75,7 @@ protected SecureEETCommunication(final ClientKey clientKey, final ServerKey serv
 
     protected EET getPort(final EndpointType endpointType) throws DnsTimeoutException, DnsLookupFailedException {
         if (wsConfiguration.getDnsLookupTimeout() > 0) {
-            final DnsResolver resolver = new DnsResolverWithTimeout(wsConfiguration.getDnsLookupTimeout());
+            final DnsLookup resolver = new DnsLookupWithTimeout(wsConfiguration.getDnsResolver(), wsConfiguration.getDnsLookupTimeout());
             final String ip = resolver.resolveAddress(endpointType.getWebserviceUrl());
             logger.info(String.format("DNS lookup resolved %s to %s", endpointType, ip));
         }

diff --git a/...etworking/DnsResolverWithTimeoutTest.java → .../networking/DnsLookupWithTimeoutTest.java b/...etworking/DnsResolverWithTimeoutTest.java → .../networking/DnsLookupWithTimeoutTest.java
@@ -1,6 +1,7 @@
 package cz.tomasdvorak.eet.client.networking;
 
 import cz.tomasdvorak.eet.client.config.EndpointType;
+import cz.tomasdvorak.eet.client.dto.DnsResolver;
 import cz.tomasdvorak.eet.client.exceptions.DnsLookupFailedException;
 import cz.tomasdvorak.eet.client.exceptions.DnsTimeoutException;
 import org.junit.Assert;
@@ -11,16 +12,17 @@
 import java.net.UnknownHostException;
 import java.util.concurrent.TimeoutException;
 
-public class DnsResolverWithTimeoutTest {
+public class DnsLookupWithTimeoutTest {
 
-    private DnsResolver resolver;
+    private DnsLookup resolver;
 
     @Before
     public void setUp() throws Exception {
-        resolver = new DnsResolverWithTimeout(100) {
+
+        final DnsResolver resolverImpl = new DnsResolver() {
             @Override
-            protected String doResolve(final String host) throws UnknownHostException {
-                if("pg.eet.cz".equals(host)) {
+            public String getHostAddress(final String host) throws UnknownHostException {
+                if ("pg.eet.cz".equals(host)) {
                     return "5.145.105.129";
                 } else if ("nonsense-timeouting.tomas-dvorak.cz".equals(host)) {
                     try {
@@ -34,7 +36,7 @@ protected String doResolve(final String host) throws UnknownHostException {
                 }
             }
         };
-
+        this.resolver = new DnsLookupWithTimeout(resolverImpl, 100);
     }
 
     @Test(timeout = 10000)