trona-evolutions

trona-evolitions

Often your migration scenarios are as good as ORM you using. Sometimes it leads to inability (without some extra efforts) to use all features of your chosen DB. This library allows you to write migration scenarios using sql and run them with a single console command.

Usage example

foo@bar:~$ trona-evolutions --init
Initializing evolutions table evolutions

CREATE TABLE evolutions (
    id INTEGER NOT NULL,
    checksum VARCHAR(32) NOT NULL,
    down_script TEXT NOT NULL,
    primary key (id)
);

Evolutions table successfully created!
foo@bar:~$ trona-evolutions
Running evolve script

--- 1.sql ---

CREATE TABLE Customers (
    id INTEGER NOT NULL,
    name VARCHAR(32) NOT NULL,
    description TEXT NOT NULL,
    primary key (id)
);

Evolution is successful!

foo@bar:~$

Installation and configuration

First you need to install trona-evolutions globally via npm

foo@bar:~$ npm install -g trona-evolutions

Than you need to setup simple configuration file named .trona-config.js and containing script that exports object containing fields:

• runQuery - MANDATORY callback that accepts SQL as it's first argument and returns Promise object which is rejected in case of failure of said query and in case of SELECT query successfully executed contains array of selected rows in form of an object {[field]: value}.
• tableName - OPTIONALLY name of tha table that would contain information about evolutions, it would be created automatically by init script. Default - "evolutions".
• evolutionsFolderPath - OPTIONALLY relative path to folder that contains .sql files of migration scripts if form of a sring or string[]. Default - "evolutions".

Example of a config for mysql database:

const mysql = require('mysql');

const con = mysql.createConnection({
    host: "localhost",
    user: "root",
    password: "123",
    database: 'playground',
});

con.connect(function(err) {
    if (err) throw err;
    console.log("Connected!");
});

module.exports = {
    evolutionsFolderPath: ['db', 'evolutions'],
    tableName: 'my_evolutions',
    runQuery (query) {
        return new Promise((resolve, reject) => {
            con.query(query, (err, result) => {
                if (err) {
                    reject(err);
                } else {
                    resolve(result);
                }
            });
        })
    }
}

After module have been installed run command and .trona-config.js created run

foo@bar:~$ trona-evolutions --init

This command will create table with information about evolutions. Than create a folder with for your evolutions script and add your first evolution to it. Note the rules which you should follow writing said evolutions:

• Name file {evolution-number}.sql (e.g. 1.sql)
• Write up and fallback scripts in file and separate them via "#DOWN" comment as at the example below

Folder content example:

- evolutions
    - 1.sql
    - 2.sql
    - 3.sql
    ...

Evolution contents example:

CREATE TABLE Customers (
    id INTEGER NOT NULL,
    name VARCHAR(32) NOT NULL,
    description TEXT NOT NULL,
    primary key (id)
);

#DOWN

DROP TABLE Customers;

Run command

foo@bar:~$ trona-evolutions

Usage

After you managed to successfully setup trona-evolutions you can run trona-evolutions-run command. This command will automatically detect any changed or new files in your evolutions folder, run respected fallback scripts if needed and than evolve your databae schema (e. g. if you have 1.sql, 2.sql, and 3.sql evolutions already in your database, you have changed 2.sql and added 4.sql it will run fallback for 3.sql and 2.sql and than run 2.sql, 3.sql, and 4.sql scripts)