app-builder/README.md

Promise based composable functions for middleware

# app-builder

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Create composable promise based middleware pipelines, using the "onion" middleware model.

## Install:

`npm install app-builder`

## Example

```javascript
import { compose } from 'app-builder'

const app = compose([
  async function (ctx, next) {
    ctx.value += 1
    await next()
    ctx.value += 4
  },
  async function (ctx, next) {
    ctx.value += 2
    await next()
    ctx.value += 3
  }
]);

const context = { value: '' }
app(context).then(() => console.log(context.value)) // --> '1234'

```

All composed functions are also valid middleware functions.

```javascript
const superApp = compose(
  async function (ctx, next) {
    ctx.value += 'first'
    await next()
    ctx.value += 'last'
  },
  app
)
```