Add client#close

brianc · brianc · commit 19a2d26fc189 · 2014-09-24T23:42:51.000-04:00
Closes brianc#6
diff --git a/README.md b/README.md
@@ -65,6 +65,11 @@ Read `rowCount` rows from the cursor instance.  The `callback` will be called wh
 
 If the cursor has read to the end of the result sets all subsequent calls to `cursor#read` will return a 0 length array of rows.  I'm open to other ways to signal the end of a cursor, but this has worked out well for me so far.
 
+
+#### cursor#close(function callback(Error err))
+
+Closes the backend portal before itterating through the entire result set.  Useful when you want to 'abort' out of a read early but continue to use the same client for other queries after the cursor is finished.
+
 ### install
 
 ```sh
diff --git a/index.js b/index.js
@@ -124,6 +124,17 @@ Cursor.prototype.end = function(cb) {
   this.connection.stream.once('end', cb)
 }
 
+Cursor.prototype.close = function(cb) {
+  this.connection.close({type: 'P'})
+  this.connection.sync()
+  this.state = 'done'
+  if(cb) {
+    this.connection.once('closeComplete', function() {
+      cb()
+    })
+  }
+}
+
 Cursor.prototype.read = function(rows, cb) {
   var self = this
   if(this.state == 'idle') {
diff --git a/package.json b/package.json
@@ -12,7 +12,7 @@
   "author": "Brian M. Carlson",
   "license": "MIT",
   "devDependencies": {
-    "pg.js": "~2.8.1",
+    "pg.js": "~3.4.4",
     "mocha": "~1.17.1"
   },
   "dependencies": {}
diff --git a/test/close.js b/test/close.js
@@ -0,0 +1,35 @@
+var assert = require('assert')
+var Cursor = require('../')
+var pg = require('pg.js')
+
+var text = 'SELECT generate_series as num FROM generate_series(0, 50)'
+describe('close', function() {
+  beforeEach(function(done) {
+    var client = this.client = new pg.Client()
+    client.connect(done)
+    client.on('drain', client.end.bind(client))
+  })
+
+  it('closes cursor early', function(done) {
+    var cursor = new Cursor(text)
+    this.client.query(cursor)
+    this.client.query('SELECT NOW()', done)
+    cursor.read(25, function(err, res) {
+      assert.ifError(err)
+      cursor.close()
+    })
+  })
+
+  it('works with callback style', function(done) {
+    var cursor = new Cursor(text)
+    var client = this.client
+    client.query(cursor)
+    cursor.read(25, function(err, res) {
+      assert.ifError(err)
+      cursor.close(function(err) {
+        assert.ifError(err)
+        client.query('SELECT NOW()', done)
+      })
+    })
+  })
+})
