jh-common-dataaccess/src/PostgreHelper.js

common-dataaccess

const pg = require('pg');
const DatabaseHelper = require('./DatabaseHelper');

module.exports = class PostgreHelper extends DatabaseHelper {
	constructor() {
		super(arguments[0]);
	}
	connect() {
		return new Promise((resolve, reject) => {
			const connection = new pg.Client(this.config);
			connection
				.connect()
				.then(() => {
					resolve(connection);
				})
				.catch(err => {
					this.print(err);
					reject('postgre connect error');
				});
		});
	}
	query(sqlstr) {
		return new Promise((resolve, reject) => {
			this.connect().then(client => {
				client.query(sqlstr, function(error, results) {
					if (error) {
						reject(error);
					} else {
						results.rows.forEach(row => {
							Object.keys(row).forEach(key => {
								if (row[key] instanceof Date) {
									row[key] = this.formatDate(row[key]);
								}
							});
						});
						resolve(results.rows);
					}
					client.end();
				});
			});
		});
	}
	execute(sqlstr) {
		return new Promise((resolve, reject) => {
			this.connect().then(client => {
				client.query(sqlstr, function(error, results) {
					if (error) {
						reject(error);
					} else {
						resolve(results.rowCount >= 1);
					}
					client.end();
				});
			});
		});
	}
	translate(transParams) {
		return new Promise((resolve, reject) => {
			this.connect().then(client => {
				const keylist = [];
				const valuelist = [];
				transParams.sql.split(' ').forEach(item => {
					item.split('=').forEach(cell => {
						if (/@.+$/.test(cell)) {
							keylist.push(cell);
							const p = transParams.l_dp.find(o => o.paramsname === cell.replace('@', ''));
							if (p.paramsvalue instanceof Date) {
								p.paramsvalue = this.formatDate(p.paramsvalue);
							}
							valuelist.push(p.paramsvalue);
						}
					});
				});
				keylist.forEach((key, index) => {
					transParams.sql = transParams.sql.replace(key, '$' + (index + 1));
				});
				client.query(transParams.sql, valuelist, function(error, results) {
					if (error) {
						reject(error);
					} else {
						resolve(results.rowCount >= 1);
					}
					client.end();
				});
			});
		});
	}
	static datapager(pageno, pagesize, sqlstr, sp) {
		return ` ${sqlstr} order by "${sp.Field}" ${sp.SortDirection || ''} limit ${pagesize} offset ${(pageno - 1) *
			pagesize} `;
	}
};