Serverless framework env conf example

handler.js

'use strict';
const connection = {
  client: 'mysql',
  connection: {
      host : process.env.HOST,
      user : process.env.USER,
      password : process.env.PASSWORD,
      database : process.env.DATABASE
  },
  pool: { min: 1, max: 10 },
  debug: true
};

const knex = require('knex')(connection);
const TABLE_TODO = 'todo';

//## Create TODO Table
module.exports.createTodoTable = async (event, context) => {
  if(await knex.schema.hasTable(TABLE_TODO)){
    return response(403, 'Table '+ TABLE_TODO+ ' already exist');
  }

  const table = await knex.schema.createTable(TABLE_TODO, function(table) {
    table.increments('id').primary();
    table.string('text');
    table.dateTime("created_at").defaultTo(knex.fn.now());
    table.dateTime("updated_at");
    table.dateTime("deleted_at");
  });
  
  return response(200,table);
};

//## Insert value into TODO table
module.exports.addToTodoTable = async (event, context) => {
  const body = (process.env.ENV === 'local') ? event.body : JSON.parse(event.body);
  
  if(!await knex.schema.hasTable(TABLE_TODO)){
    return response(403, 'Table '+ TABLE_TODO+ ' not exist');
  }

  const table = await knex(TABLE_TODO).insert([body])
  
  return response(200,table);
};

function response(statusCode, body) {
  return {
    statusCode: statusCode,
    body: JSON.stringify(body),
  }
};

serverless.env.yml

#### Serverless framework environment configuration example 
dev:
  ENV: 'dev'
  HOST: 'your host here'
  USER: 'your user here'
  PASSWORD: 'your password here'
  DATABASE: 'your database here'

prod:
  ENV: 'prod'
  HOST: 'your host here'
  USER: 'your user here'
  PASSWORD: 'your password here'
  DATABASE: 'your database here'

local:
  ENV: 'local'
  HOST: 'your host here'
  USER: 'your user here'
  PASSWORD: 'your password here'
  DATABASE: 'your database here'

serverless.yml

service: sls-msql 

provider:

  name: aws
  runtime: nodejs8.10
  region: us-east-2
  stage: dev

  environment:
    ENV: ${file(./serverless.env.yml):${opt:stage, self:provider.stage}.ENV}
    HOST: ${file(./serverless.env.yml):${opt:stage, self:provider.stage}.HOST}
    USER: ${file(./serverless.env.yml):${opt:stage, self:provider.stage}.USER}
    PASSWORD: ${file(./serverless.env.yml):${opt:stage, self:provider.stage}.PASSWORD}
    DATABASE: ${file(./serverless.env.yml):${opt:stage, self:provider.stage}.DATABASE}

  vpc:
    securityGroupIds:
       - securityGroupId1
    subnetIds:
       - subnetId1
       - subnetId2

functions:
  createTodoTable:
    handler: handler.createTodoTable

  ## serverless invoke local -f addToTodoTable --data '{ "queryStringParameters": {"text":"abcd"}}'  
  addToTodoTable:
    handler: handler.addToTodoTable  
    events:
    - http:
        path: todo
        method: post