Client: Max execute retries #7

README.md

@@ -24,15 +24,18 @@ var hosts = ['host1:9042', 'host2:9042', 'host3', 'host4'];
 var cqlClient = new Client({hosts: hosts, keyspace: 'Keyspace1'});
 ```
 Client() accepts an object with these slots:
-
-         hosts : String list in host:port format. Port is optional (defaults to 9042).
-      keyspace : Name of keyspace to use.
-      username : User for authentication (optional).
-      password : Password for authentication (optional).
-       version : Currently only '3.0.0' is supported (optional).
-     staleTime : Time in milliseconds before trying to reconnect(optional).
-
-Queries are performed using the `execute()`. For example:
+```
+            hosts : String list in host:port format. 
+                    Port is optional (defaults to 9042).
+         keyspace : Name of keyspace to use (optional).
+         username : User for authentication (optional).
+         password : Password for authentication (optional).
+          version : Currently only '3.0.0' is supported (optional).
+        staleTime : Time in milliseconds before trying to reconnect(optional).
+maxExecuteRetries : Maximum amount of times an execute can be retried
+                    using another connection, in case the server is unhealthy (optional).
+```
+Queries are performed using the `execute()` method. For example:
 ```javascript
 // Reading
 cqlClient.execute('SELECT key, email, last_name FROM user_profiles WHERE key=?', ['jbay'],
@@ -94,7 +97,7 @@ con.open(function(err) {
 Instances of `Client()` and `Connection()` are `EventEmitter`'s and emit `log` events:
 ```javascript
 var Connection = require('node-cassandra-cql').Connection;
-var con = new Connection({host:'host1', port:9042, keyspace:'Keyspace1', username:'user', password:'password'});
+var con = new Connection({host:'host1', port:9042, keyspace:'Keyspace1'});
 con.on('log', function(level, message) {
   console.log('log event: %s -- %j', level, message);
 });

index.js

@@ -174,7 +174,7 @@ Client.prototype.getAConnection = function (callback) {
  Executes a query in an available connection.
  @param {function} callback, executes callback(err, result) when finished
  */
-Client.prototype.execute = function (query, args, consistency, callback) {
+Client.prototype.execute = function (query, args, consistency, callback, retryCount) {
   if(typeof callback === 'undefined') {
     if (typeof consistency === 'undefined') {
       //only the query and the callback was specified
@@ -202,9 +202,16 @@ Client.prototype.execute = function (query, args, consistency, callback) {
       if (self.isServerUnhealthy(err)) {
         //if its a fatal error, set the connection to unhealthy
         self.setUnhealthy(c);
-        self.emit('log', 'error', 'There was an error executing a query, retrying execute (will get another connection)', err);
-        //retry, it will get another connection
-        self.execute.call(self, query, args, consistency, callback, retryCount);
+        retryCount = (!retryCount) ? 0 : retryCount;
+        if (retryCount === self.options.maxExecuteRetries) {
+          callback(err, result, retryCount);
+        }
+        else {
+          //retry, it will get another connection
+          self.emit('log', 'error', 'There was an error executing a query, retrying execute (will get another connection)', err);
+          retryCount++;
+          self.execute.call(self, query, args, consistency, callback, retryCount);
+        }
       }
       else {
         //If the result is OK or there is error (syntax error or an unauthorized for example), callback

package.json

@@ -1,7 +1,7 @@
 {
   "author": "Jorge Bay <jorgebaygondra@gmail.com>",
   "name": "node-cassandra-cql",
-  "version": "0.1.7",
+  "version": "0.1.8",
   "description": "Node.js driver for Cassandra CQL3 binary protocol",
   "keywords": [
     "cassandra",

test/clientTests.js

@@ -54,20 +54,37 @@ module.exports = {
             callback(null);
           }
         });
-      }/*,
+      },
       function (callback) {
         //no query params
-        client.execute('SELECT * FROM system.schema_keyspaces', function(err){
+        client.execute('SELECT * FROM system.schema_keyspaces', function(err) {
           callback(err);
         });
-      }*/
+      }
     ],
     //all finished
     function(err){
       test.ok(err === null, err);
       test.done();
     });
   },
+  'max execute retries': function (test) {
+    //Only 1 retry
+    client.options.maxExecuteRetries = 1;
+    var isServerUnhealthyOriginal = client.isServerUnhealthy;
+
+    //Change the behaviour so every err is a "server error"
+    client.isServerUnhealthy = function (err) {
+      return true;
+    };
+
+    client.execute('WILL FAIL AND EXECUTE THE METHOD FROM ABOVE', function (err, result, retryCount){
+      test.ok(err, 'The execution must fail');
+      test.equal(retryCount, client.options.maxExecuteRetries, 'It must retry executing the times specified');
+      client.isServerUnhealthy = isServerUnhealthyOriginal;
+      test.done();
+    });
+  },
   'shutdown': function(test) {
     client.shutdown(function(){
       test.done();