node-postgres/lib/native/index.js

121 lines
3.3 KiB
JavaScript

//require the c++ bindings & export to javascript
var sys = require('sys');
var EventEmitter = require('events').EventEmitter;
var utils = require(__dirname + "/../utils");
var binding = require(__dirname + '/../../build/default/binding');
var Connection = binding.Connection;
var types = require(__dirname + "/../types");
var NativeQuery = require(__dirname + '/query');
var p = Connection.prototype;
var nativeConnect = p.connect;
p.connect = function() {
var self = this;
utils.buildLibpqConnectionString(this._config, function(err, conString) {
if(err) return self.emit('error', err);
nativeConnect.call(self, conString);
})
}
p.query = function(config, values, callback) {
var q = new NativeQuery(config, values, callback);
this._queryQueue.push(q);
this._pulseQueryQueue();
return q;
}
p._pulseQueryQueue = function(initialConnection) {
if(!this._connected) {
return;
}
if(this._activeQuery) {
return;
}
var query = this._queryQueue.shift();
if(!query) {
if(!initialConnection) {
this._drainPaused ? this._drainPaused++ : this.emit('drain');
}
return;
}
this._activeQuery = query;
if(query.name) {
if(this._namedQueries[query.name]) {
this._sendQueryPrepared(query.name, query.values||[]);
} else {
this._namedQuery = true;
this._namedQueries[query.name] = true;
this._sendPrepare(query.name, query.text, (query.values||[]).length);
}
}
else if(query.values) {
//call native function
this._sendQueryWithParams(query.text, query.values)
} else {
//call native function
this._sendQuery(query.text);
}
}
p.pauseDrain = function() {
this._drainPaused = 1;
};
p.resumeDrain = function() {
if(this._drainPaused > 1) {
this.emit('drain')
};
this._drainPaused = 0;
};
var clientBuilder = function(config) {
config = config || {};
var connection = new Connection();
connection._queryQueue = [];
connection._namedQueries = {};
connection._activeQuery = null;
connection._config = utils.normalizeConnectionInfo(config);
//attach properties to normalize interface with pure js client
connection.user = connection._config.user;
connection.password = connection._config.password;
connection.database = connection._config.database;
connection.host = connection._config.host;
connection.port = connection._config.port;
connection.on('connect', function() {
connection._connected = true;
connection._pulseQueryQueue(true);
});
//proxy some events to active query
connection.on('_row', function(row) {
connection._activeQuery.handleRow(row);
})
connection.on('_error', function(err) {
//give up on trying to wait for named query prepare
this._namedQuery = false;
if(connection._activeQuery) {
connection._activeQuery.handleError(err);
} else {
connection.emit('error', err);
}
})
connection.on('_readyForQuery', function() {
var q = this._activeQuery;
//a named query finished being prepared
if(this._namedQuery) {
this._namedQuery = false;
this._sendQueryPrepared(q.name, q.values||[]);
} else {
connection._activeQuery.handleReadyForQuery();
connection._activeQuery = null;
connection._pulseQueryQueue();
}
});
return connection;
};
module.exports = clientBuilder;