https://github.com/scopsy/typescript-param-validator

Typescript runtime parameters validation
https://github.com/scopsy/typescript-param-validator

decorators es2017 javascript typescript validation

Last synced: 3 months ago
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Typescript runtime parameters validation

• Host: GitHub
• URL: https://github.com/scopsy/typescript-param-validator
• Owner: scopsy
• License: mit
• Created: 2018-01-17T00:07:09.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2018-01-17T14:02:13.000Z (almost 7 years ago)
• Last Synced: 2024-09-19T18:05:53.681Z (4 months ago)
• Topics: decorators, es2017, javascript, typescript, validation
• Language: TypeScript
• Homepage:
• Size: 246 KB
• Stars: 12
• Watchers: 2
• Forks: 2
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • Contributing: CONTRIBUTING.md
  • License: LICENSE
  • Code of conduct: code-of-conduct.md

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README

        
# Typescript runtime param validation

A library for runtime param validations using typescript decorators

that works with `class-validator` library.

 

Useful when you need to validate parameter data coming from untyped source(i.e http body, and etc...) or when you need to perform complex validations on the input params.

Using the param validation decorator you can declare your validation on the type annotation and leave the validation work to `class-validator` 

## Install

```bash

npm install --save typescript-param-validator class-validators

```

## Examples

```typescript

import { Validator, Validate } from 'typescript-param-validator';

import { IsDate, IsNotEmpty, MaxDate, IsEmail, Length } from 'class-validators';

class DataDto {

  @IsNotEmpty()

  @IsEmail()

  email: string;

  

  @Length(10, 200)

  @IsNotEmpty()

  description: string;

  

  @IsDate()

  @IsNotEmpty()

  @MaxDate(new Date())

  birthDate: Date;

}

class TestClass {

  @Validate()

  methodName(@Validator() data: DataDto) {

    

  }

  @Validate()

  serverControllerEndpoint(@Validator(DataDto, 'body') req: Request) {

    

  }

}

const instance = new TestClass();

// Will throw class-validator errors on runtime

instance.methodName({

  birthDate: new Date(),

  description: '123',

  email: 'fakemail'

});

instance.serverControllerEndpoint({

  body: {

    birthDate: new Date(),

    description: '123',

    email: 'fakemail'

  }

});

```

### Catching the Validation errors

In order to catch the validation errors you need to check if the errors is instanceof `ValidatorError`;

```typescript

import { ValidatorError } from 'typescript-param-validator';

try {

  // ... code

} catch (error) {

  if (error instanceof ValidatorError) {

    // here you have access to the validationErrors object that 

    // will contain array of `class-validator` error objects.

    console.log(error.validationErrors);

  }

}

```