From 4ba1ddb666b35731d983ad56478022c09e5e9b85 Mon Sep 17 00:00:00 2001
From: Christian Kvalheim <christkv@gmail.com>
Date: Wed, 19 Sep 2012 14:48:21 -0400
Subject: [PATCH] Fixed eval to work with system.js collection functions, Issue
 #709

---
 lib/mongodb/commands/db_command.js |  1 +
 lib/mongodb/cursor.js              | 16 ++-----------
 lib/mongodb/db.js                  | 24 +++++++++++--------
 test/db_test.js                    | 38 +++++++++++++++++++++++++++---
 4 files changed, 52 insertions(+), 27 deletions(-)

diff --git a/lib/mongodb/commands/db_command.js b/lib/mongodb/commands/db_command.js
index 2b535f15291..87438e8ffee 100644
--- a/lib/mongodb/commands/db_command.js
+++ b/lib/mongodb/commands/db_command.js
@@ -32,6 +32,7 @@ DbCommand.SYSTEM_INDEX_COLLECTION = "system.indexes";
 DbCommand.SYSTEM_PROFILE_COLLECTION = "system.profile";
 DbCommand.SYSTEM_USER_COLLECTION = "system.users";
 DbCommand.SYSTEM_COMMAND_COLLECTION = "$cmd";
+DbCommand.SYSTEM_JS_COLLECTION = "system.js";
 
 // New commands
 DbCommand.NcreateIsMasterCommand = function(db, databaseName) {
diff --git a/lib/mongodb/cursor.js b/lib/mongodb/cursor.js
index 28395aea6d9..e27dc3655b3 100644
--- a/lib/mongodb/cursor.js
+++ b/lib/mongodb/cursor.js
@@ -658,22 +658,10 @@ Cursor.prototype.explain = function(callback) {
 };
 
 /**
- * Returns a stream object that can be used to listen to and stream records
- * (**Use the CursorStream object instead as this is deprected**)
- *
- * Options
- *  - **fetchSize** {Number} the number of records to fetch in each batch (steam specific batchSize).
- *
- * Events
- *  - **data** {function(item) {}} the data event triggers when a document is ready.
- *  - **error** {function(err) {}} the error event triggers if an error happens.
- *  - **end** {function() {}} the end event triggers when there is no more documents available.
- *
- * @param {Object} [options] additional options for streamRecords.
- * @return {EventEmitter} returns a stream object.
- * @api public
+ * @ignore
  */
 Cursor.prototype.streamRecords = function(options) {
+  console.log("[WARNING] streamRecords method is deprecated, please use stream method which is much faster");
   var args = Array.prototype.slice.call(arguments, 0);
   options = args.length ? args.shift() : {};
 
diff --git a/lib/mongodb/db.js b/lib/mongodb/db.js
index 82beb632f2d..a625d1085c4 100644
--- a/lib/mongodb/db.js
+++ b/lib/mongodb/db.js
@@ -533,6 +533,7 @@ Db.prototype.eval = function(code, parameters, options, callback) {
   } else if(parameters != null && parameters.constructor == Array && typeof parameters !== 'function') {
     finalParameters = parameters;
   }
+
   // Create execution selector
   var selector = {'$eval':finalCode, 'args':finalParameters};
   // Check if the nolock parameter is passed in
@@ -540,17 +541,20 @@ Db.prototype.eval = function(code, parameters, options, callback) {
     selector['nolock'] = options['nolock'];
   }
 
-  // Iterate through all the fields of the index
-  new Cursor(this, new Collection(this, DbCommand.SYSTEM_COMMAND_COLLECTION), selector, options, 0, -1)
-    .setReadPreference(ReadPreference.PRIMARY)
-    .nextObject(function(err, result) {
-      if(err != null) return callback(err, null);
+  // Set primary read preference
+  options.readPreference = ReadPreference.PRIMARY;
 
-      if(result.ok == 1) {
-        callback(null, result.retval);
-      } else {
-        callback(new Error("eval failed: " + result.errmsg), null); return;
-      }
+  // Execute the eval
+  this.collection(DbCommand.SYSTEM_COMMAND_COLLECTION).findOne(selector, options, function(err, result) {
+    if(err) return callback(err);
+
+    if(result && result.ok == 1) {
+      callback(null, result.retval);
+    } else if(result) {
+      callback(new Error("eval failed: " + result.errmsg), null); return;
+    } else {
+      callback(err, result);
+    }
   });
 };
 
diff --git a/test/db_test.js b/test/db_test.js
index 4d33175a1ad..cbada14d7ba 100644
--- a/test/db_test.js
+++ b/test/db_test.js
@@ -184,6 +184,7 @@ exports.shouldCorrectlyExecuteEvalFunctions = function(test) {
 
   // Establish connection to db
   db.open(function(err, db) {
+    var numberOfTests = 
 
     // Evaluate a function on the server with the parameter 3 passed in
     db.eval('function (x) {return x;}', [3], function(err, result) {
@@ -234,7 +235,6 @@ exports.shouldCorrectlyExecuteEvalFunctions = function(test) {
     // Evaluate a statement using the code object including a scope
     db.eval(new Code("i + 3;", {'i':2}), function(err, result) {
       test.equal(5, result);
-      test.done();
     });
 
     // Evaluate an illegal statement
@@ -242,11 +242,43 @@ exports.shouldCorrectlyExecuteEvalFunctions = function(test) {
       test.ok(err instanceof Error);
       test.ok(err.message != null);
       // Let's close the db
+      db.close();
       test.done();
     });
+  });
+}
 
-    db.close();
-    test.done();
+/**
+ * Defining and calling a system level javascript function (NOT recommended, http://www.mongodb.org/display/DOCS/Server-side+Code+Execution)
+ *
+ * @_class db
+ * @_function eval
+ * @ignore
+ */
+exports.shouldCorrectlyDefineSystemLevelFunctionAndExecuteFunction = function(test) {
+  var db = new Db('integration_tests', new Server("127.0.0.1", 27017,
+   {auto_reconnect: false, poolSize: 1, ssl:useSSL}), {native_parser: native_parser});
+
+  // Establish connection to db
+  db.open(function(err, db) {
+
+    // Clean out the collection
+    db.collection("system.js").remove({}, {safe:true}, function(err, result) {
+      test.equal(null, err);
+
+      // Define a system level function
+      db.collection("system.js").insert({_id: "echo", value: new Code("function(x) { return x; }")}, {safe:true}, function(err, result) {
+        test.equal(null, err);
+      
+        db.eval("echo(5)", function(err, result) {
+          test.equal(null, err);
+          test.equal(5, result);
+
+          db.close();
+          test.done();
+        });
+      });
+    });
   });
 }