Implement idempotent REST publishing

lib/src/main/java/io/ably/lib/debug/DebugOptions.java

@@ -18,8 +18,8 @@ public interface RawProtocolListener {
 
 	public interface RawHttpListener {
 		public void onRawHttpRequest(String id, HttpURLConnection conn, String method, String authHeader, Map<String, List<String>> requestHeaders, HttpCore.RequestBody requestBody);
-		public void onRawHttpResponse(String id, HttpCore.Response response);
-		public void onRawHttpException(String id, Throwable t);
+		public void onRawHttpResponse(String id, String method, HttpCore.Response response);
+		public void onRawHttpException(String id, String method, Throwable t);
 	}
 
 	public DebugOptions(String key) throws AblyException { super(key); }

lib/src/main/java/io/ably/lib/http/HttpCore.java

@@ -232,11 +232,12 @@ <T> T httpExecute(HttpURLConnection conn, String method, Param[] headers, Reques
 			}
 			response = readResponse(conn);
 			if(rawHttpListener != null) {
-				rawHttpListener.onRawHttpResponse(id, response);
+				rawHttpListener.onRawHttpResponse(id, method, response);
 			}
 		} catch(IOException ioe) {
+			ioe.printStackTrace();
 			if(rawHttpListener != null) {
-				rawHttpListener.onRawHttpException(id, ioe);
+				rawHttpListener.onRawHttpException(id, method, ioe);
 			}
 			throw AblyException.fromThrowable(ioe);
 		}

lib/src/main/java/io/ably/lib/rest/Channel.java

@@ -18,6 +18,7 @@
 import io.ably.lib.types.Param;
 import io.ably.lib.types.PresenceMessage;
 import io.ably.lib.types.PresenceSerializer;
+import io.ably.lib.util.Crypto;
 
 /**
  * A class representing a Channel in the Ably REST API.
@@ -93,11 +94,22 @@ private Http.Request<Void> publishImpl(final Message[] messages) {
 		return ably.http.request(new Http.Execute<Void>() {
 			@Override
 			public void execute(HttpScheduler http, final Callback<Void> callback) throws AblyException {
+				/* handle message ids */
+				boolean hasClientSuppliedId = false;
 				for(Message message : messages) {
+					/* RSL1k2 */
+					hasClientSuppliedId |= (message.id != null);
 					/* RTL6g3 */
 					ably.auth.checkClientId(message, true, false);
 					message.encode(options);
 				}
+				if(!hasClientSuppliedId && ably.options.idempotentRestPublishing) {
+					/* RSL1k1: populate the message id with a library-generated id */
+					String messageId = Crypto.getRandomMessageId();
+					for (int i = 0; i < messages.length; i++) {
+						messages[i].id = messageId + ':' + i;
+					}
+				}
 
 				HttpCore.RequestBody requestBody = ably.options.useBinaryProtocol ? MessageSerializer.asMsgpackRequest(messages) : MessageSerializer.asJsonRequest(messages);
 

lib/src/main/java/io/ably/lib/transport/Defaults.java

@@ -3,9 +3,12 @@
 import io.ably.lib.BuildConfig;
 import io.ably.lib.types.ClientOptions;
 
+import java.text.DecimalFormat;
+
 public class Defaults {
 	/* versions */
-	public static final String ABLY_VERSION         = "1.0";
+	public static final float ABLY_VERSION_NUMBER   = 1.0f;
+	public static final String ABLY_VERSION         = new DecimalFormat("0.0").format(ABLY_VERSION_NUMBER);
 	public static final String ABLY_LIB_VERSION     = String.format("%s-%s", BuildConfig.LIBRARY_NAME, BuildConfig.VERSION);
 
 	/* params */

lib/src/main/java/io/ably/lib/types/ClientOptions.java

@@ -125,6 +125,11 @@ public ClientOptions(String key) throws AblyException {
 	 */
 	public String environment;
 
+	/**
+	 * Spec: TO3n
+	 */
+	public boolean idempotentRestPublishing = (Defaults.ABLY_VERSION_NUMBER >= 1.2);
+
 	/**
 	 * Spec: TO313
 	 */

lib/src/main/java/io/ably/lib/util/Crypto.java

@@ -299,6 +299,12 @@ private static final int getPaddedLength(int plaintextLength) {
 		};
 	}
 
+	public static String getRandomMessageId() {
+		byte[] entropy = new byte[9];
+		secureRandom.nextBytes(entropy);
+		return Base64Coder.encode(entropy).toString();
+	}
+
 	/**
 	 * Determine whether or not 256-bit AES is supported. (If this determines that
 	 * it is not supported, install the JCE unlimited strength JCE extensions).

lib/src/test/java/io/ably/lib/test/common/Helpers.java

@@ -725,7 +725,7 @@ public void onRawHttpRequest(String id, HttpURLConnection conn, String method, S
 		}
 
 		@Override
-		public void onRawHttpResponse(String id, HttpCore.Response response) {
+		public void onRawHttpResponse(String id, String method, HttpCore.Response response) {
 			/* duplicating if necessary, ensure lower-case versions of header names are present */
 			Map<String, List<String>> headers = response.headers;
 			Map<String, List<String>> normalisedHeaders = new HashMap<String, List<String>>();
@@ -744,7 +744,7 @@ public void onRawHttpResponse(String id, HttpCore.Response response) {
 		}
 
 		@Override
-		public void onRawHttpException(String id, Throwable t) {
+		public void onRawHttpException(String id, String method, Throwable t) {
 			RawHttpRequest req = get(id);
 			if(req != null) {
 				req.error = t;

lib/src/test/java/io/ably/lib/test/rest/RestAuthTest.java

@@ -1390,10 +1390,10 @@ public void onRawHttpRequest(String id, HttpURLConnection conn, String method, S
 					}
 
 					@Override
-					public void onRawHttpResponse(String id, HttpCore.Response response) {}
+					public void onRawHttpResponse(String id, String method, HttpCore.Response response) {}
 
 					@Override
-					public void onRawHttpException(String id, Throwable t) {}
+					public void onRawHttpException(String id, String method, Throwable t) {}
 				};
 			}};
 			fillInOptions(options);
@@ -1457,10 +1457,10 @@ public void onRawHttpRequest(String id, HttpURLConnection conn, String method, S
 					}
 
 					@Override
-					public void onRawHttpResponse(String id, HttpCore.Response response) {}
+					public void onRawHttpResponse(String id, String method, HttpCore.Response response) {}
 
 					@Override
-					public void onRawHttpException(String id, Throwable t) {}
+					public void onRawHttpException(String id, String method, Throwable t) {}
 				};
 			}};
 			fillInOptions(options);