aws-samples / aws-lambda-with-rdb

Database schema management in a serverless way

Serverless Database Schema Management for RDBMS

Overview

This sample shows you how to manage schema of RDBMS such as Amazon RDS, leveraging AWS Lambda and sqldef, an idempotent and declarative SQL schema management tool. You can also seed initial data to your database tables, allowing you to fit this sample in various use cases.

Just for example this sample deploys an Amazon RDS Aurora MySQL/Postgres cluster, but you can use the mechanism with any MySQL/Postgres clusters as long as Lambda can connect to them.

Architecture

There is only one CDK stack. The architecture is shown below.

Directory Structures

.
├── bin
│   ├── db-definer.ts              # Define CDK Stack
│   └── db-settings.ts             # Define type of database family (PostgreSQL, MySQL) settings
├── lambda
│   └── db-definer
│       ├── schema                 # Table Definition. SQL file in this folder will be executed
│       └── seed
│           ├── mysql              # Seed SQL file for MySQL
│           └── postgresql         # Seed SQL file for PostgreSQL
└── lib
    ├── database.ts                # Amazon Aurora and AWS Lambda are defined here
    └── db-definer-stack.ts        # VPC and database

Main Libraries

• aws-cdk
• typescript
• sqldef
  • For more information, please see below.
  • k0kubun/sqldef: Idempotent schema management for MySQL, PostgreSQL, and more

Prerequisites

• npm
• aws cli v2
• cdk
• docker
• configuration of aws profile

Getting Started

1. Clone the repository

• Run git clone command to download the source code.

2. Deploy resources

• Run npm ci command in the top of this directory.
• Run npx cdk deploy to deploy these resouces.
• When resouces are successfully deployed, outputs such as DbDefinerStack.DBDBLambdaName will be shown in the terminal. These values will be used to define tables.
• You can edit DDL in ./lambda/db-definer/schema and DML in ./lambda/db-definer/seed before deploy.

Outputs:
DbDefinerStack.DBDBLambdaNameXXXXXXX = DbDefinerStack-DBDbDefinerXXXXXX
Stack ARN:
arn:aws:cloudformation:xyz-region-x:XXXXXXXXXXX:stack/DbDefinerStack/XXXXXXXXXXXXXXXXXX

3. Define Table

DbDefinerStack.DBDBLambdaName accept these command from event.

1. init
   Drop and create database. You can use this command under developing. SQL file in ./lambda/db-definer/schema will be reflected.
2. preview
   Preview change the definition of table from SQL file in ./lambda/db-definer/schema by using sqldef.
3. sync
   Synchronize table in database to SQL file in ./lambda/db-definer/schema by using sqldef.
   You can preview SQL that will be excuted by sqldef.
4. seed
   Run SQL file in ./lambda/db-definer/seed/mysql or ./lambda/db-definer/seed/postgresql.
   You can use this command for inserting seed data to database.

For example, when you want to initialize DB, run below command in the terminal.
You can excute this lambda from AWS Management Console.

aws lambda invoke --function-name [DbDefinerStack.DBDBLambdaName] --payload '{"command":"init"}' --cli-binary-format raw-in-base64-out res.txt

Security

See CONTRIBUTING for more information.

License

This library is licensed under the MIT-0 License. See the LICENSE file.