Nest-logging-transport

Logger for NestJS framework allowing you to
use custom transports (or use predefined ones).

Installation

yarn:

``sh
yarn add nest-logging-transport
`

npm:

`sh
npm i nest-logging-transport
`

Usage

Nest-logging-transport allows you to either define your own transport, or use predefined ones.

Example with predefined transport:

`ts
import { NestTransportLogger, DefaultTransportConsole } from 'nest-logging-transport';

const customLogger = new NestTransportLogger({
transports: [new DefaultTransportConsole()],
});

const bootstrap = async () => {
const logger = new Logger('Bootstrap');
const app = await NestFactory.create(ExampleModule, { logger: customLogger });
logger.log('Application ready');
[...]
await app.listen(3334, () => logger.log('Server listening'));
};
`

From this moment all log calls will be redirected to NestTransportLogger instance and then
to each transport defined in instance constructor.

$3

Creating own transport required implementing all methods from interface Transport.
To do it, simply create new object (or class):

`ts
import { Transport, LogEvent, LogEventWithReplacedNulls } from 'nest-logging-transport';

const customTransport = {
log(event: LogEvent, eventWithoutNulls: LogEventWithReplacedNulls) {
// [...]
},
// [...]
};
`

You can find examples in src/transports.

#### Difference between log events

To make operating on logs easier there is event with nulls replaced with empty strings ''.
Normal log:

`js
{
additionalContext: null,
stacktrace: null,
baseContext: 'Bootstrap',
type: 'log',
timestamp: 2022-03-23T19:26:59.295Z,
message: 'Server listening'
}
`

Log with replaced nulls:

`js
{
additionalContext: '',
stacktrace: '',
baseContext: 'Bootstrap',
type: 'log',
timestamp: 2022-03-23T19:26:59.295Z,
message: 'Server listening'
}
`

Log functions in your logger can take event with nulls as first argument and without
nulls as the second one.

Examples

Logs from default (console) transport looks like this:

!image showing example log output

You can also use preview script, available after cloning the repository:

`sh
yarn preview
`

Publishing package (for package maintainers and forks)

Publishing this package is semi-automated.
Steps to do that:

1. Clone repository and checkout branch you want to release
2. Install dependencies from current lockfile yarn install --frozen-lockfile
3. Use release scripts:
1. yarn release- in most cases, release script will take care of giving package the right number
2. yarn release:patch- when you want to change only last part of semver (x.x.X)
3. yarn release:minor- when you want to change middle part of semver (x.X.x)
4. yarn release:major- when you want to change first part of semver (X.x.x)
4. Push created tags using git push --follow-tags origin master`. Don't use npm publish.

You can read more about semver on semver.org page.

This project will follow semver from first major release (versions starting with 0 will be considered beta versions and will not follow semver).