node-query/lib/NodeQuery.js

71 lines
1.6 KiB
JavaScript
Executable File

'use strict';
let fs = require('fs'),
helpers = require('./helpers'),
QueryBuilder = require('./QueryBuilder');
/**
* Class for connection management
*/
class NodeQuery {
/**
* Constructor
*
* @private
* @constructor
*/
constructor() {
this.instance = null;
}
/**
* Create a query builder object
*
* @param {String} driverType - The name of the database type, eg. mysql or pg
* @param {Object} connObject - A connection object from the database library you are connecting with
* @param {String} [connLib] - The name of the db connection library you are using, eg. mysql or mysql2. Optional if the same as driverType
* @return {QueryBuilder} - The Query Builder object
*/
init(driverType, connObject, connLib) {
connLib = connLib || driverType;
let paths = {
driver: `${__dirname}/drivers/${helpers.upperCaseFirst(driverType)}`,
adapter: `${__dirname}/adapters/${connLib}`,
};
Object.keys(paths).forEach(type => {
try {
fs.statSync(`${paths[type]}.js`);
} catch (e) {
throw new Error(
`Selected ${type} (${helpers.upperCaseFirst(driverType)}) does not exist!`
);
}
});
let driver = require(paths.driver);
let $adapter = require(paths.adapter);
let adapter = new $adapter(connObject);
this.instance = new QueryBuilder(driver, adapter);
return this.instance;
}
/**
* Return an existing query builder instance
*
* @return {QueryBuilder} - The Query Builder object
*/
getQuery() {
if (this.instance == null) {
throw new Error('No Query Builder instance to return');
}
return this.instance;
}
}
module.exports = new NodeQuery();