@loopback/cli
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Yeoman generator for LoopBack 4
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# Decorators
## Overview
Decorators provide annotations for class methods and arguments. Decorators use
the form `@decorator` where `decorator` is the name of the function that will be
called at runtime.
## Basic Usage
### txIdFromHeader
This simple decorator allows you to annotate a `Controller` method argument. The
decorator will annotate the method argument with the value of the header
`X-Transaction-Id` from the request.
**Example**
```ts
class MyController {
@get('/')
getHandler(@txIdFromHeader() txId: string) {
return `Your transaction id is: ${txId}`;
}
}
```
## Related Resources
You can check out the following resource to learn more about decorators and how
they are used in LoopBack Next.
- [TypeScript Handbook: Decorators](https://www.typescriptlang.org/docs/handbook/decorators.html)
- [Decorators in LoopBack](http://loopback.io/doc/en/lb4/Decorators.html)