Added support to log requests/responses when communicating with the GitLab API (#228).

src/main/java/org/gitlab4j/api/GitLabApi.java

@@ -4,6 +4,7 @@ import java.util.Collections;
 import java.util.Map;
 import java.util.Optional;
 import java.util.WeakHashMap;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.ws.rs.core.MediaType;
@@ -23,7 +24,7 @@ import org.gitlab4j.api.utils.SecretString;
  */
 public class GitLabApi {
 
-    private final static Logger LOG = Logger.getLogger(GitLabApi.class.getName());
+    private final static Logger LOGGER = Logger.getLogger(GitLabApi.class.getName());
 
     /** GitLab4J default per page.  GitLab will ignore anything over 100. */
     public static final int DEFAULT_PER_PAGE = 100;
@@ -85,7 +86,7 @@ public class GitLabApi {
      * @return the GitLab4J shared Logger instance
      */
     public static final Logger getLogger() {
-        return (LOG);
+        return (LOGGER);
     }
 
     /**
@@ -638,6 +639,69 @@ public class GitLabApi {
         apiClient = new GitLabApiClient(apiVersion, hostUrl, tokenType, authToken, secretToken, clientConfigProperties);
     }
 
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API
+     * using the GitLab4J shared Logger instance and Level.FINE as the level.
+     *
+     * @return this GitLabApi instance
+     */
+    public GitLabApi withRequestResponseLogging() {
+        enableRequestResponseLogging();
+        return (this);
+    }
+
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API
+     * using the GitLab4J shared Logger instance.
+     *
+     * @param level the logging level (SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST)
+     * @return this GitLabApi instance
+     */
+    public GitLabApi withRequestResponseLogging(Level level) {
+        enableRequestResponseLogging(level);
+        return (this);
+    }
+
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API.
+     *
+     * @param logger the Logger instance to log to
+     * @param level the logging level (SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST)
+     * @return this GitLabApi instance
+     */
+    public GitLabApi withRequestResponseLogging(Logger logger, Level level) {
+        enableRequestResponseLogging(logger, level);
+        return (this);
+    }
+
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API
+     * using the GitLab4J shared Logger instance and Level.FINE as the level.
+     */
+    public void enableRequestResponseLogging() {
+        enableRequestResponseLogging(LOGGER, Level.FINE);
+    }
+
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API
+     * using the GitLab4J shared Logger instance.
+     *
+     * @param level the logging level (SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST)
+     */
+    public void enableRequestResponseLogging(Level level) {
+        enableRequestResponseLogging(LOGGER, level);
+    }
+
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API.
+     *
+     * @param logger the Logger instance to log to
+     * @param level the logging level (SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST)
+     */
+    public void enableRequestResponseLogging(Logger logger, Level level) {
+        this.apiClient.enableRequestResponseLogging(logger, level);
+    }
+
     /**
      * Sets up all future calls to the GitLab API to be done as another user specified by sudoAsUsername.
      * To revert back to normal non-sudo operation you must call unsudo(), or pass null as the username.
@@ -1413,5 +1477,4 @@ public class GitLabApi {
 
         return wikisApi;
     }
-
 }

src/main/java/org/gitlab4j/api/GitLabApiClient.java

@@ -12,6 +12,8 @@ import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
 import java.util.List;
 import java.util.Map;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.SSLContext;
@@ -36,6 +38,7 @@ import org.gitlab4j.api.utils.JacksonJson;
 import org.glassfish.jersey.apache.connector.ApacheConnectorProvider;
 import org.glassfish.jersey.client.ClientConfig;
 import org.glassfish.jersey.client.ClientProperties;
+import org.glassfish.jersey.logging.LoggingFeature;
 import org.glassfish.jersey.media.multipart.FormDataMultiPart;
 import org.glassfish.jersey.media.multipart.MultiPart;
 import org.glassfish.jersey.media.multipart.MultiPartFeature;
@@ -237,6 +240,24 @@ public class GitLabApiClient {
         clientConfig.register(MultiPartFeature.class);
     }
 
+    /**
+     * Enable the logging of the requests to and the responses from the GitLab server API.
+     *
+     * @param logger the Logger instance to log to
+     * @param level the logging level (SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST)
+     */
+    void enableRequestResponseLogging(Logger logger, Level level) {
+
+        LoggingFeature loggingFeature = new LoggingFeature(
+            logger, level, LoggingFeature.Verbosity.PAYLOAD_TEXT, LoggingFeature.DEFAULT_MAX_ENTITY_SIZE);
+        clientConfig.register(loggingFeature);
+
+        // Recreate the Client instance if already created.
+        if (apiClient != null) {
+            createApiClient();
+        }
+    }
+
     /**
      * Get the auth token being used by this client.
      *
@@ -629,18 +650,22 @@ public class GitLabApiClient {
         return (invocation(url, queryParams, MediaType.APPLICATION_JSON));
     }
 
+    protected Client createApiClient() {
+
+        ClientBuilder clientBuilder = ClientBuilder.newBuilder().withConfig(clientConfig);
+
+        if (ignoreCertificateErrors) {
+            clientBuilder.sslContext(openSslContext).hostnameVerifier(openHostnameVerifier);
+        }
+
+        apiClient = clientBuilder.build();
+        return (apiClient);
+    }
+
     protected Invocation.Builder invocation(URL url, MultivaluedMap<String, String> queryParams, String accept) {
 
         if (apiClient == null) {
-            if (ignoreCertificateErrors) {
-                apiClient = ClientBuilder.newBuilder()
-                        .withConfig(clientConfig)
-                        .sslContext(openSslContext)
-                        .hostnameVerifier(openHostnameVerifier)
-                        .build();
-            } else {
-                apiClient = ClientBuilder.newBuilder().withConfig(clientConfig).build();
-            }
+            createApiClient();
         }
 
         WebTarget target = apiClient.target(url.toExternalForm()).property(ClientProperties.FOLLOW_REDIRECTS, true);