Better error messages

pom.xml

@@ -46,6 +46,14 @@
           </execution>
         </executions>
       </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
       <plugin>
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>findbugs-maven-plugin</artifactId>

src/main/java/org/kohsuke/github/GitHub.java

@@ -31,6 +31,7 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.Reader;
+import java.net.HttpURLConnection;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.text.ParseException;
@@ -55,6 +56,8 @@
 import com.fasterxml.jackson.databind.introspect.VisibilityChecker.Std;
 import com.infradna.tool.bridge_method_injector.WithBridgeMethods;
 import java.nio.charset.Charset;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 /**
  * Root of the GitHub API.
@@ -68,6 +71,8 @@
  * @author Kohsuke Kawaguchi
  */
 public class GitHub {
+    protected final transient Logger logger = Logger.getLogger(getClass().getName());
+
     /*package*/ final String login;
 
     /**
@@ -458,6 +463,8 @@ public boolean isCredentialValid() throws IOException {
             retrieve().to("/user", GHUser.class);
             return true;
         } catch (IOException e) {
+            if (logger.isLoggable(Level.FINE))
+                logger.log(Level.FINE, "Exception validating credentials on " + this.apiUrl + " with login '" + this.login + "' " + e, e);
             return false;
         }
     }

src/main/java/org/kohsuke/github/HttpException.java

@@ -0,0 +1,118 @@
+package org.kohsuke.github;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+import javax.annotation.CheckForNull;
+
+/**
+ * {@link IOException} for http exceptions because {@link HttpURLConnection} throws un-discerned
+ * {@link IOException} and it can help to know the http response code to decide how to handle an
+ * http exceptions.
+ *
+ * @author <a href="mailto:[email protected]">Cyrille Le Clerc</a>
+ */
+public class HttpException extends IOException {
+    static final long serialVersionUID = 1L;
+
+    private final int responseCode;
+    private final String responseMessage;
+    private final String url;
+
+    /**
+     * @param message         The detail message (which is saved for later retrieval
+     *                        by the {@link #getMessage()} method)
+     * @param responseCode    Http response code. {@code -1} if no code can be discerned.
+     * @param responseMessage Http response message
+     * @param url             The url that was invoked
+     * @see HttpURLConnection#getResponseCode()
+     * @see HttpURLConnection#getResponseMessage()
+     */
+    public HttpException(String message, int responseCode, String responseMessage, String url) {
+        super(message);
+        this.responseCode = responseCode;
+        this.responseMessage = responseMessage;
+        this.url = url;
+    }
+
+    /**
+     * @param message         The detail message (which is saved for later retrieval
+     *                        by the {@link #getMessage()} method)
+     * @param responseCode    Http response code. {@code -1} if no code can be discerned.
+     * @param responseMessage Http response message
+     * @param url             The url that was invoked
+     * @param cause           The cause (which is saved for later retrieval by the
+     *                        {@link #getCause()} method).  (A null value is permitted,
+     *                        and indicates that the cause is nonexistent or unknown.)
+     * @see HttpURLConnection#getResponseCode()
+     * @see HttpURLConnection#getResponseMessage()
+     */
+    public HttpException(String message, int responseCode, String responseMessage, String url, Throwable cause) {
+        super(message, cause);
+        this.responseCode = responseCode;
+        this.responseMessage = responseMessage;
+        this.url = url;
+    }
+
+    /**
+     * @param message         The detail message (which is saved for later retrieval
+     *                        by the {@link #getMessage()} method)
+     * @param responseCode    Http response code. {@code -1} if no code can be discerned.
+     * @param responseMessage Http response message
+     * @param url             The url that was invoked
+     * @param cause           The cause (which is saved for later retrieval by the
+     *                        {@link #getCause()} method).  (A null value is permitted,
+     *                        and indicates that the cause is nonexistent or unknown.)
+     * @see HttpURLConnection#getResponseCode()
+     * @see HttpURLConnection#getResponseMessage()
+     */
+    public HttpException(int responseCode, String responseMessage, String url, Throwable cause) {
+        super("Server returned HTTP response code: " + responseCode + ", message: '" + responseMessage + "'" +
+                " for URL: " + url, cause);
+        this.responseCode = responseCode;
+        this.responseMessage = responseMessage;
+        this.url = url;
+    }
+
+    /**
+     * @param responseCode    Http response code. {@code -1} if no code can be discerned.
+     * @param responseMessage Http response message
+     * @param url             The url that was invoked
+     * @param cause           The cause (which is saved for later retrieval by the
+     *                        {@link #getCause()} method).  (A null value is permitted,
+     *                        and indicates that the cause is nonexistent or unknown.)
+     * @see HttpURLConnection#getResponseCode()
+     * @see HttpURLConnection#getResponseMessage()
+     */
+    public HttpException(int responseCode, String responseMessage, @CheckForNull URL url, Throwable cause) {
+        this(responseCode, responseMessage, url == null ? null : url.toString(), cause);
+    }
+
+    /**
+     * Http response code of the request that cause the exception
+     *
+     * @return {@code -1} if no code can be discerned.
+     */
+    public int getResponseCode() {
+        return responseCode;
+    }
+
+    /**
+     * Http response message of the request that cause the exception
+     *
+     * @return {@code null} if no response message can be discerned.
+     */
+    public String getResponseMessage() {
+        return responseMessage;
+    }
+
+    /**
+     * The http URL that caused the exception
+     *
+     * @return url
+     */
+    public String getUrl() {
+        return url;
+    }
+}

src/main/java/org/kohsuke/github/Requester.java

@@ -48,6 +48,8 @@
 import java.util.Locale;
 import java.util.Map;
 import java.util.NoSuchElementException;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.zip.GZIPInputStream;
@@ -64,7 +66,9 @@
  */
 class Requester {
     private static final List<String> METHODS_WITHOUT_BODY = asList("GET", "DELETE");
-
+
+    protected final transient Logger logger = Logger.getLogger(getClass().getName());
+
     private final GitHub root;
     private final List<Entry> args = new ArrayList<Entry>();
     private final Map<String,String> headers = new LinkedHashMap<String, String>();
@@ -473,21 +477,33 @@ private void setupConnection(URL url) throws IOException {
     }
 
     private <T> T parse(Class<T> type, T instance) throws IOException {
-        if (uc.getResponseCode()==304)
-            return null;    // special case handling for 304 unmodified, as the content will be ""
         InputStreamReader r = null;
+        int responseCode = -1;
+        String responseMessage = null;
         try {
+            responseCode = uc.getResponseCode();
+            responseMessage = uc.getResponseMessage();
+            if (responseCode == 304) {
+                return null;    // special case handling for 304 unmodified, as the content will be ""
+            }
+
             r = new InputStreamReader(wrapStream(uc.getInputStream()), "UTF-8");
             String data = IOUtils.toString(r);
             if (type!=null)
                 try {
                     return MAPPER.readValue(data,type);
                 } catch (JsonMappingException e) {
-                    throw (IOException)new IOException("Failed to deserialize "+data).initCause(e);
+                    throw (IOException)new IOException("Failed to deserialize " +data).initCause(e);
                 }
             if (instance!=null)
                 return MAPPER.readerForUpdating(instance).<T>readValue(data);
             return null;
+        } catch (FileNotFoundException e) {
+            // java.net.URLConnection handles 404 exception has FileNotFoundException, don't wrap exception in HttpException
+            // to preserve backward compatibility
+            throw e;
+        } catch (IOException e) {
+            throw new HttpException(responseCode, responseMessage, uc.getURL(), e);
         } finally {
             IOUtils.closeQuietly(r);
         }
@@ -508,7 +524,18 @@ private InputStream wrapStream(InputStream in) throws IOException {
      * Handle API error by either throwing it or by returning normally to retry.
      */
     /*package*/ void handleApiError(IOException e) throws IOException {
-        if (uc.getResponseCode() == 401) // Unauthorized == bad creds
+        int responseCode;
+        try {
+            responseCode = uc.getResponseCode();
+        } catch (IOException e2) {
+            // likely to be a network exception (e.g. SSLHandshakeException),
+            // uc.getResponseCode() and any other getter on the response will cause an exception
+            if (logger.isLoggable(Level.FINE))
+                logger.log(Level.FINE, "Silently ignore exception retrieving response code for '" + uc.getURL() + "'" +
+                        " handling exception " + e, e);
+            throw e;
+        }
+        if (responseCode == HttpURLConnection.HTTP_UNAUTHORIZED) // 401 / Unauthorized == bad creds
             throw e;
 
         if ("0".equals(uc.getHeaderField("X-RateLimit-Remaining"))) {