Add support for (fallback_)application_name

lib/client.js

@@ -52,18 +52,12 @@ Client.prototype.connect = function(callback) {
     if(self.ssl) {
       con.requestSsl();
     } else {
-      con.startup({
-        user: self.user,
-        database: self.database
-      });
+      con.startup(self.getStartupConf());
     }
   });
 
   con.on('sslconnect', function() {
-    con.startup({
-      user: self.user,
-      database: self.database
-    });
+    con.startup(self.getStartupConf());
   });
 
   function checkPgPass(cb) {
@@ -194,6 +188,23 @@ Client.prototype.connect = function(callback) {
 
 };
 
+Client.prototype.getStartupConf = function() {
+  var params = this.connectionParameters;
+
+  var data = {
+    user     : params.user ,
+    database : params.database
+    // client_encoding : "'".concat(params.client_encoding).concat("'")
+  };
+
+  var appName = params.application_name || params.fallback_application_name;
+  if (appName) {
+    data.application_name = appName;
+  }
+
+  return data;
+};
+
 Client.prototype.cancel = function(client, query) {
   if(client.activeQuery == query) {
     var con = this.connection;

lib/connection-parameters.js

@@ -3,9 +3,17 @@ var path = require('path');
 
 var defaults = require(__dirname + '/defaults');
 
-var val = function(key, config) {
+var val = function(key, config, envVar) {
+  if (envVar === undefined) {
+    envVar = process.env[ 'PG' + key.toUpperCase() ];
+  } else if (envVar === false) {
+    // do nothing ... use false
+  } else {
+    envVar = process.env[ envVar ];
+  }
+
   return config[key] ||
-    process.env['PG' + key.toUpperCase()] ||
+    envVar ||
     defaults[key];
 };
 
@@ -22,6 +30,14 @@ var parse = function(str) {
   if(/ |%[^a-f0-9]|%[a-f0-9][^a-f0-9]/i.test(str)) str = encodeURI(str);
   var result = url.parse(str, true);
   config = {};
+
+  if (result.query.application_name) {
+    config.application_name = result.query.application_name;
+  }
+  if (result.query.fallback_application_name) {
+    config.fallback_application_name = result.query.fallback_application_name;
+  }
+
   if(result.protocol == 'socket:') {
     config.host = decodeURI(result.pathname);
     config.database = result.query.db;
@@ -68,6 +84,9 @@ var ConnectionParameters = function(config) {
   this.client_encoding = val("client_encoding", config);
   //a domain socket begins with '/'
   this.isDomainSocket = (!(this.host||'').indexOf('/'));
+
+  this.application_name = val('application_name', config, 'PGAPPNAME');
+  this.fallback_application_name = val('fallback_application_name', config, false);
 };
 
 var add = function(params, config, paramName) {
@@ -82,6 +101,9 @@ ConnectionParameters.prototype.getLibpqConnectionString = function(cb) {
   add(params, this, 'user');
   add(params, this, 'password');
   add(params, this, 'port');
+  add(params, this, 'application_name');
+  add(params, this, 'fallback_application_name');
+
   if(this.database) {
     params.push("dbname='" + this.database + "'");
   }

lib/connection.js

@@ -117,16 +117,19 @@ Connection.prototype.requestSsl = function(config) {
 };
 
 Connection.prototype.startup = function(config) {
-  var bodyBuffer = this.writer
+  var writer = this.writer
     .addInt16(3)
     .addInt16(0)
-    .addCString('user')
-    .addCString(config.user)
-    .addCString('database')
-    .addCString(config.database)
-    .addCString('client_encoding')
-    .addCString("'utf-8'")
-    .addCString('').flush();
+  ;
+
+  Object.keys(config).forEach(function(key){
+    var val = config[key];
+    writer.addCString(key).addCString(val);
+  });
+
+  writer.addCString('client_encoding').addCString("'utf-8'");
+
+  var bodyBuffer = writer.addCString('').flush();
   //this message is sent without a code
 
   var length = bodyBuffer.length + 4;

lib/defaults.js

@@ -38,7 +38,10 @@ var defaults = module.exports = {
 
   client_encoding: "",
 
-  ssl: false
+  ssl: false,
+
+  application_name : undefined,
+  fallback_application_name: undefined
 };
 
 //parse int8 so you can get your count values as actual numbers

test/integration/client/appname-tests.js

@@ -0,0 +1,89 @@
+var helper = require('./test-helper');
+var Client = helper.Client;
+
+var conInfo = helper.config;
+
+function getConInfo(override) {
+  var newConInfo = {};
+  Object.keys(conInfo).forEach(function(k){
+    newConInfo[k] = conInfo[k];
+  });
+  Object.keys(override || {}).forEach(function(k){
+    newConInfo[k] = override[k];
+  });
+  return newConInfo;
+}
+
+function getAppName(conf, cb) {
+  var client = new Client(conf);
+  client.connect(assert.success(function(){
+    client.query('SHOW application_name', assert.success(function(res){
+      var appName = res.rows[0].application_name;
+      cb(appName);
+      client.end();
+    }));
+  }));
+}
+
+test('No default appliation_name ', function(){
+  var conf = getConInfo();
+  getAppName(conf, function(res){
+    assert.strictEqual(res, '');
+  });
+});
+
+test('fallback_application_name is used', function(){
+  var fbAppName = 'this is my app';
+  var conf = getConInfo({
+    'fallback_application_name' : fbAppName
+  });
+  getAppName(conf, function(res){
+    assert.strictEqual(res, fbAppName);
+  });
+});
+
+test('application_name is used', function(){
+  var appName = 'some wired !@#$% application_name';
+  var conf = getConInfo({
+    'application_name' : appName
+  });
+  getAppName(conf, function(res){
+    assert.strictEqual(res, appName);
+  });
+});
+
+test('application_name has precedence over fallback_application_name', function(){
+  var appName = 'some wired !@#$% application_name';
+  var fbAppName = 'some other strange $$test$$ appname';
+  var conf = getConInfo({
+    'application_name' : appName ,
+    'fallback_application_name' : fbAppName
+  });
+  getAppName(conf, function(res){
+    assert.strictEqual(res, appName);
+  });
+});
+
+test('application_name from connection string', function(){
+  var appName = 'my app';
+  var conf = 'postgres:///?application_name='+appName;
+  getAppName(conf, function(res){
+    assert.strictEqual(res, appName);
+  });
+});
+
+
+
+// TODO: make the test work for native client too
+if (!helper.args.native) {
+ test('application_name is read from the env', function(){
+    var appName = process.env.PGAPPNAME = 'testest';
+    var conf = getConInfo({
+      'just some bla' : 'to fool the pool'
+    });
+    getAppName(conf, function(res){
+      delete process.env.PGAPPNAME;
+      assert.strictEqual(res, appName);
+    });
+  });
+}