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Resume Client API for Socket.IO and Node.JS - Medical Speech to Summarized Text
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# pino-abstract-transport
[](https://www.npmjs.com/package/pino-abstract-transport)
[](https://github.com/pinojs/pino-abstract-transport/actions)
[](https://snyk.io/test/github/pinojs/pino-abstract-transport)
[](https://coveralls.io/github/pinojs/pino-abstract-transport?branch=master)
[](https://standardjs.com/)
Write Pino transports easily.
## Install
```
npm i pino-abstract-transport
```
## Usage
```js
import build from 'pino-abstract-transport'
export default async function (opts) {
return build(async function (source) {
for await (let obj of source) {
console.log(obj)
}
})
}
```
or in CommonJS and streams:
```js
'use strict'
const build = require('pino-abstract-transport')
module.exports = function (opts) {
return build(function (source) {
source.on('data', function (obj) {
console.log(obj)
})
})
}
```
## Typescript usage
Install the type definitions for node. Make sure the major version of the type definitions matches the node version you are using.
#### Node 16
```
npm i -D @types/node@16
```
## API
### build(fn, opts) => Stream
Create a [`split2`](http://npm.im/split2) instance and returns it.
This same instance is also passed to the given function, which is called
synchronously.
If `opts.transform` is `true`, `pino-abstract-transform` will
wrap the split2 instance and the returned stream using [`duplexify`](https://www.npmjs.com/package/duplexify),
so they can be concatenated into multiple transports.
#### Events emitted
In addition to all events emitted by a [`Readable`](https://nodejs.org/api/stream.html#stream_class_stream_readable)
stream, it emits the following events:
* `unknown` where an unparsable line is found, both the line and optional error is emitted.
#### Options
* `parse` an option to change to data format passed to build function. Default: `undefined`.
* `close(err, cb)` a function that is called to shutdown the transport. It's called both on error and non-error shutdowns.
It can also return a promise. In this case discard the the `cb` argument.
* `parseLine(line)` a function that is used to parse line received from `pino`.
## Example
### custom parseLine
You can allow custom `parseLine` from users while providing a simple and safe default parseLine.
```js
'use strict'
const build = require('pino-abstract-transport')
function defaultParseLine (line) {
const obj = JSON.parse(line)
// property foo will be added on each line
obj.foo = 'bar'
return obj
}
module.exports = function (opts) {
const parseLine = typeof opts.parseLine === 'function' ? opts.parseLine : defaultParseLine
return build(function (source) {
source.on('data', function (obj) {
console.log(obj)
})
}, {
parseLine: parseLine
})
}
```
### Stream concatenation / pipeline
You can pipeline multiple transports:
```js
const build = require('pino-abstract-transport')
const { Transform, pipeline } = require('stream')
function buildTransform () {
return build(function (source) {
return new Transform({
objectMode: true,
autoDestroy: true,
transform (line, enc, cb) {
line.service = 'bob'
cb(null, JSON.stringify(line))
}
})
}, { enablePipelining: true })
}
function buildDestination () {
return build(function (source) {
source.on('data', function (obj) {
console.log(obj)
})
})
}
pipeline(process.stdin, buildTransform(), buildDestination(), function (err) {
console.log('pipeline completed!', err)
})
```
## License
MIT