Add debugging flag

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

@@ -430,6 +430,20 @@ public GitLabApi(String hostUrl, String personalAccessToken, Map<String, Object>
          this(ApiVersion.V4, hostUrl, TokenType.PRIVATE, personalAccessToken, null, clientConfigProperties);
      }
 
+     /**
+      *  Constructs a GitLabApi instance set up to interact with the GitLab server specified by GitLab API version.
+      *
+      * @param apiVersion the ApiVersion specifying which version of the API to use
+      * @param hostUrl the URL of the GitLab server
+      * @param tokenType the type of auth the token is for, PRIVATE or ACCESS
+      * @param authToken to token to use for access to the API
+      * @param secretToken use this token to validate received payloads
+      * @param clientConfigProperties Map instance with additional properties for the Jersey client connection
+      */
+     public GitLabApi(ApiVersion apiVersion, String hostUrl, TokenType tokenType, String authToken, String secretToken, Map<String, Object> clientConfigProperties) {
+         this(apiVersion, hostUrl, tokenType, authToken, secretToken, clientConfigProperties, false);
+     }
+
     /**
      *  Constructs a GitLabApi instance set up to interact with the GitLab server specified by GitLab API version.
      *
@@ -439,12 +453,13 @@ public GitLabApi(String hostUrl, String personalAccessToken, Map<String, Object>
      * @param authToken to token to use for access to the API
      * @param secretToken use this token to validate received payloads
      * @param clientConfigProperties Map instance with additional properties for the Jersey client connection
+     * @param debugging log http requests and responses
      */
-    public GitLabApi(ApiVersion apiVersion, String hostUrl, TokenType tokenType, String authToken, String secretToken, Map<String, Object> clientConfigProperties) {
+    public GitLabApi(ApiVersion apiVersion, String hostUrl, TokenType tokenType, String authToken, String secretToken, Map<String, Object> clientConfigProperties, boolean debugging) {
         this.apiVersion = apiVersion;
         this.gitLabServerUrl = hostUrl;
         this.clientConfigProperties = clientConfigProperties;
-        apiClient = new GitLabApiClient(apiVersion, hostUrl, tokenType, authToken, secretToken, clientConfigProperties);
+        apiClient = new GitLabApiClient(apiVersion, hostUrl, tokenType, authToken, secretToken, clientConfigProperties, debugging);
     }
 
     /**

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

@@ -14,6 +14,7 @@
 import java.util.function.Supplier;
 import java.util.logging.Level;
 import java.util.logging.Logger;
+
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.SSLContext;
 import javax.net.ssl.SSLEngine;
@@ -30,6 +31,7 @@
 import javax.ws.rs.core.MultivaluedMap;
 import javax.ws.rs.core.Response;
 import javax.ws.rs.core.StreamingOutput;
+
 import org.gitlab4j.api.Constants.TokenType;
 import org.gitlab4j.api.GitLabApi.ApiVersion;
 import org.gitlab4j.api.utils.JacksonJson;
@@ -39,6 +41,7 @@
 import org.glassfish.jersey.client.ClientProperties;
 import org.glassfish.jersey.client.JerseyClientBuilder;
 import org.glassfish.jersey.jackson.JacksonFeature;
+import org.glassfish.jersey.logging.LoggingFeature;
 import org.glassfish.jersey.media.multipart.BodyPart;
 import org.glassfish.jersey.media.multipart.Boundary;
 import org.glassfish.jersey.media.multipart.FormDataBodyPart;
@@ -212,6 +215,22 @@ public GitLabApiClient(ApiVersion apiVersion, String hostUrl, String privateToke
      * @param clientConfigProperties the properties given to Jersey's clientconfig
      */
     public GitLabApiClient(ApiVersion apiVersion, String hostUrl, TokenType tokenType, String authToken, String secretToken, Map<String, Object> clientConfigProperties) {
+        this(apiVersion, hostUrl, tokenType, authToken, secretToken, clientConfigProperties, false);
+    }
+
+    /**
+     * Construct an instance to communicate with a GitLab API server using the specified GitLab API version,
+     * server URL and private token.
+     *
+     * @param apiVersion the ApiVersion specifying which version of the API to use
+     * @param hostUrl the URL to the GitLab API server
+     * @param tokenType the type of auth the token is for, PRIVATE or ACCESS
+     * @param authToken the private token to authenticate with
+     * @param secretToken use this token to validate received payloads
+     * @param clientConfigProperties the properties given to Jersey's clientconfig
+     * @param debugging log http requests and responses
+     */
+    public GitLabApiClient(ApiVersion apiVersion, String hostUrl, TokenType tokenType, String authToken, String secretToken, Map<String, Object> clientConfigProperties, boolean debugging) {
 
         // Remove the trailing "/" from the hostUrl if present
         this.hostUrl = (hostUrl.endsWith("/") ? hostUrl.replaceAll("/$", "") : hostUrl);
@@ -240,6 +259,11 @@ public GitLabApiClient(ApiVersion apiVersion, String hostUrl, TokenType tokenTyp
             }
         }
 
+        if (debugging) {
+            clientConfig.register(new LoggingFeature(java.util.logging.Logger.getLogger(LoggingFeature.DEFAULT_LOGGER_NAME), java.util.logging.Level.INFO, LoggingFeature.Verbosity.PAYLOAD_ANY, 1024 * 50 /* Log payloads up to 50K */));
+            clientConfig.property(LoggingFeature.LOGGING_FEATURE_VERBOSITY, LoggingFeature.Verbosity.PAYLOAD_ANY);
+        }
+
         // Disable auto-discovery of feature and services lookup, this will force Jersey
         // to use the features and services explicitly configured by gitlab4j
         clientConfig.property(ClientProperties.FEATURE_AUTO_DISCOVERY_DISABLE, true);