Zend Expressive Content Validation

Introduction

Zend Expressive Content Validation is a Middleware for automating validation of incoming input.

Allows the following:

• Defining named input filters.
• Mapping named input filters to routes.
• Returning a PSR-7 response representation of application/problem with validation error messages on invalid input using Zend Problem Details

Installation

Run the following composer command:

$ composer require mvlabs/ze-content-validation

Configuration

The ze-content-validation key is a mapping between routes names as the key, and the value being an array of mappings that determine which HTTP method to respond to and what input filter to map to for the given request. The keys for the mapping can either be an HTTP method or * wildcard for applying to any http method.

Example:

'ze-content-validation' => [
    'user.add' => [
        'POST' =>  \App\InputFilter\UserInputFilter::class
    ],
],

In the above example, the \App\InputFilter\UserInputFilter will be selected for POST requests.

input_filter_spec

input_filter_spec is for configuration-driven creation of input filters. The keys for this array will be a unique name, but more often based off the service name it is mapped to under the ze-content-validation key. The values will be an input filter configuration array, as is described in the ZF2 manual section on input filters.

Example:

    'input_filter_specs' => [
        'App\\InputFilter\\LoginInputFilter' => [
            0 => [
                'name' => 'displayName',
                'required' => true,
                'filters' =>[],
                'validators' => [
                     0 => [
                        'name' => 'not_empty',
                     ]   
                ],
                
            ],
            1 => [
                'name' => 'password',
                'required' => true,
                'filters' => [],
                'validators' => [
                    0 => [
                        'name' => 'not_empty',
                    ],
                    1 => [
                        'name' => 'string_length',
                        'options' => [
                            'min' => 8, 
                            'max' => 12
                        ],
                    ],
                ],                
            ],
        ],
    ],

Validating

In the following request, an email value is provided with an invalid format, and the displayName field is omitted entirely:

POST /users HTTP/1.1
Accept: application/json
Content-Type: application/json; charset=utf-8

{
    "email": "foo",
    "password": "mySecretPassword!"
    
}

The response:

HTTP/1.1 422 Unprocessable Entity
Content-Type: application/problem+json

{
  "detail": "Validation Failed",
  "status": 422,
  "title": "Unprocessable Entity",
  "type": "https://httpstatus.es/422",
  "errors": {
    "email": {
        "emailAddressInvalidFormat": "The input is not a valid email address. Use the basic format local-part@hostname"
    },
    "displayName": {
      "isEmpty": "Value is required and can't be empty"
    }    
  },
}