# Loopback model validator

This package allows you to add validation to model definition. Addressing the absence of this implementation as seen in the [Validations](https://loopback.io/doc/en/lb3/Model-definition-JSON-file.html#validations) session of [Model definition JSON file](https://loopback.io/doc/en/lb3/Model-definition-JSON-file.html).

To avoid conflict with future implementations by the Loopback team, I proposed a new and simple structure in defining model properties.

This package also defines the possibility of using data filters that enable cleaner data.

# Installation

[Reference mixins in server/model-config.js](https://loopback.io/doc/en/lb3/Defining-mixins.html#reference-mixins-in-model-configjs)

```
{
  "_meta": {
    ...
    "mixins": [
      ...
      "../node_modules/loopback-model-validator/mixins"
    ]
  }
}
```
[Enable a model with mixins](https://loopback.io/doc/en/lb3/Defining-mixins.html#enable-a-model-with-mixins)

```
{
  "name": "note",
  "base": "PersistedModel",
  ...
  "mixins": {
    "Validators" : true,
    "Filters" : true
  }
  "properties": {
    ...
  },
  ...
}
```

# Validators

In defining the model, use:
```
"properties": {
  "initials": {
    "type": "string",
    "validators": {
      "length": 3
    }
  }
}
```
[More examples](https://github.com/herbertscruz/loopback-model-validator/blob/master/test/loopback/common/models/test-lab.json) of validations.

## Validations supported

| Name | Value | Description | Example |
| ---- | ----- | ----------- | ------- |
| **length** / **is** | number | Length fixed of the string ([Validatable.validatesLengthOf](https://apidocs.loopback.io/loopback-datasource-juggler/#validatable-validateslengthof)) | {"length": 3} or {"is": 3} |
| **min** | number | Length min of the string ([Validatable.validatesLengthOf](https://apidocs.loopback.io/loopback-datasource-juggler/#validatable-validateslengthof)) | {"min": 3} |
| **max** | number | Length max of the string ([Validatable.validatesLengthOf](https://apidocs.loopback.io/loopback-datasource-juggler/#validatable-validateslengthof)) | {"max": 3} |
| **pattern** | object | Format of the string ([Validatable.validatesFormatOf](https://apidocs.loopback.io/loopback-datasource-juggler/#validatable-validatesformatof)) | {"pattern": {"exp": "/\w+/", "flags": "i"}} |
| **email** | boolean | Valid email | {"email": true} |
| **urlIp** | boolean | Valid URL or IP | {"urlIp": true} |
| **cpf** | boolean | Valid CPF (Brazilian document for people) | {"cpf": true} |
| **cnpj** | boolean | Valid CNPJ (Brazilian document for companies) | {"cnpj": true} |
| **unique** | boolean | Unique value ([Validatable.validatesUniquenessOf](https://apidocs.loopback.io/loopback-datasource-juggler/#validatable-validatesuniquenessof)) | {"unique": true} |

## Loopback validations

You can use [loopback-datasource-juggler](https://loopback.io/doc/en/lb3/Validating-model-data.html#using-validation-methods) native validation methods, where the propertyName parameter will be the property and the options object the value. Example:

```
// Validatable.validatesLengthOf
"properties": {
  "initials": {
    "type": "string",
    "validators": {
      "lengthOf": {
        "is": 3,
        "allowBlank": true,
        "allowNull": true,
        "message": "length is wrong"
      }
    }
  }
}
```


# Filters

In defining the model, use:
```
"properties": {
  "initials": {
    "type": "string",
    "filters": {
      "upper": true
    }
  }
}
```
[More examples](https://github.com/herbertscruz/loopback-model-validator/blob/master/test/loopback/common/models/test-lab.json) of filters.

## Filters supported

| Name | Value | Description | Example |
| ---- | ----- | ----------- | ------- |
| **upper** | boolean | Converts string, as a whole, to upper case just like [String#toUpperCase](https://mdn.io/toUpperCase) | {"upper": true} |
| **lower** | boolean | Converts string, as a whole, to lower case just like [String#toLowerCase](https://mdn.io/toLowerCase) | {"lower": true} |
| **trim** | boolean | Removes leading and trailing whitespace or specified characters from string | {"trim": true} |
| **replace** | object | Replaces matches for *exp* in string with *replacement* | {"replace": {"pattern": {"type": "regex", "exp": "[^\\d]", "flags": "g"}, "replacement": ""} |