elc

The best practice of building Koa2 with TypeScript.

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Usage

1. Run npm init elc

2. Install dependencies: yarn

3. fill out .env.dev, and run prisma db push to synchronize the data model

4. Start the server: yarn dev. visit: http://127.0.0.1:3001/api/user/list

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Project Layout

src
├── app
│   ├── controllers         ---  server controllers
│   ├── helpers             ---  helper func (database / redis / interceptor / error handler / validator...)
│   ├── jobs                ---  task (periodic task / trigger task / email server...)
│   └── services            ---  adhesive controller and model
├── config
│   ├── constants        ---  environment variable
│   ├── koa.middlewares     ---  middlewares for Koa
│   ├── routing.middlewares ---  middlewares for Routing Controller
│   ├── routing.options     ---  configs for Routing Controller
│   ├── bootstrap           ---  lifecycle
│   └── interceptors        ---  global interceptor
│   └── utils               ---  pure functions for help
└── test                    ---  utils for testcase
├── .env           ---  environment file

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Feature

• Separation configuration and business logic.

• Test cases and lint configuration.

• The best practice for Dependency Injection in Koa project.

• Get constraints on your data model with Prisma.

• TypeScript hotload.

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Lifecycle

1. app.ts -> collect env vars constants -> collect env files variables.env

2. envs ready, call bootstrap.before()

3. lift routing-controllers -> lift Koa middlewares -> register Container for DI

4. start Koa & invoke bootstrap.after() after startup

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Databases

The project uses Prisma as the intelligent ORM tool by default. Supports PostgreSQL, MySQL and SQLite.

• You can change the data type and connection method in the .env file
• After each modification to file /prisma/schema.prisma, you need to run prisma migrate dev to migrate the database.
• After each modification to file /prisma/schema.prisma, you need to run prisma generate to sync types.

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About Environments

When nodejs is running, ENV does not mean NODE_ENV:

• After NodeJS project is built, we always run it as NODE_ENV=PRODUCTION, which may affect some framework optimizations.
• NODE_ENV only identifies the NodeJS runtime, independent of the business.
• You should use ENV to identify the environment.

For the data settings of each environment, you can refer to the following:

• Development Mode (ENV=development): read configurations from configs/constants/development.ts file, but it will still be overwritten by .env file.

• Production Mode (ENV=production): read configurations from configs/constants/production.ts file, but it will still be overwritten by .env file.

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Reference

• routing-controllers
• Prisma
• ioredis
• redlock

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LICENSE

This project is licensed under the MIT License. See the LICENSE file for more info.