MIGRATIONS/SEEDING

seed: examples include username = test, password = test, or a 'guest' account.

migration: allow to quickly build and rebuild schema in sql dbs

in practice, you'll run migrations to set up the schema, but then seed the testing data in.

//set up the express server with knex file
express directoryname --save knex pg
cd directoryname
npm install
knex init
mkdir db
touch db/knex.js
  //put this in the knex.js every time no questions:
var environment = process.env.NODE_ENV || 'development';
var config = require('../knexfile.js')[environment];
module.exports = require('knex')(config)


// create a gitignore file
touch .gitignore          // you don't want to push node files to git
echo node_modules > .gitignore


// push new repo to github
git init
git add .
git commit -m "First commit"
git remote add origin PASTE IN REPO URL HERE
git push -u origin master


// set up the knexfile.js - here's the top portion. all else stays the same for dev environment

module.exports = {

  development: {
    client: 'pg',
    connection: {
      database: 'migpract',
      host: '127.0.0.1'
    }
  },


// set up the db
createdb migrations
knex migrate:make users       - this makes the xxxxxxxx_users.js file in the migrations folder

* look in migrations folder for a file. edit the doc to include your column names and data types:

exports.up = function(knex, Promise) {
  return knex.schema.createTable('users', function(table){
    table.increments();  // ID column
    table.string('username');
    table.string('password');
    table.string('email');
  })
};
exports.down = function(knex, Promise) {
  return knex.schema.dropTable('users');
};

// now in termianl
\q
knex migrate:latest
psql migrations;
\dt
select * from migrations;

// changing schema
\q
knex migrate:rollback
// user table disappears  // does everything in the exports.down handler // now you can add to schema

knex migrate:latest
// now our db is updated
psql migrations
\dt
select * from migrations;
😃 😃 😃


SEEDING on CLI

\q
knex seed:make seed_name   // this creates a seed directory with a file in it called seed_name - chose your own name

edit knexfile.js to include a seeds key value. like so:

  development: {
    client: 'pg',
    connection: {
      database: 'migrations',
      host: '127.0.0.1'
    },
    seeds: {
      directory: './seeds'
    }
  },


edit seeds file in /seeds:

exports.seed = function(knex, Promise) {
  // Deletes ALL existing entries
  return knex('users').del()
    .then(function () {
      // Inserts seed entries
      return knex('users').insert([
        {username: 'test', password: 'test', email: "fake@fake.com", age: 12},
        {username: 'bob', password: 'bob', email: "fake@fake.com", age: 34},
        {username: 'susy', password: '12345', email: "fake@fake.com", age: 412},
        {username: 'robotron9000', password: 'test', email: "fake@fake.com", age: 12},
        {username: 'admin', password: 'admin', email: "admin@fake.com", age: 35},
      ]);
    });
};

// HERES HOW TO REFRESH YOUR MIGRATIONS AND SEED
\q
knex migrate:rollback
knex migrate:latest
knex seed:run

** if severe debugging needs to happen, delete the knex_migration & knex_migration_lock tables in the db.