How to enable Json pretty print on Apigility ApiProblem response?

Question

I would like to know how to set ApiProblem response to pretty print Json by default.

Answer 1

I've made a few changes on class ApiProblemResponse. I set the property $jsonFlags to 128, which is related to JSON_PRETTY_PRINT code.

Here's the full class code with my changes:

<?php

namespace Zend\ApiProblem;

use Zend\Http\Response;

/**
 * Represents an ApiProblem response payload
 */
class ApiProblemResponse extends Response
{
    /**
     * @var ApiProblem
     */
    protected $apiProblem;

    /**
     * Flags to use with json_encode JSON_PRETTY_PRINT
     *
     * @var int
     */
    protected $jsonFlags = 128;

    /**
     * @param ApiProblem $apiProblem
     */
    public function __construct(ApiProblem $apiProblem)
    {
        $this->apiProblem = $apiProblem;
        $this->setCustomStatusCode($apiProblem->status);
        $this->setReasonPhrase($apiProblem->title);

        // Just comment/remove these lines to prevent flags from being overwrited
        //if (defined('JSON_UNESCAPED_SLASHES')) {
          //$this->jsonFlags = constant('JSON_UNESCAPED_SLASHES');
        //}
    }

    /**
     * @return ApiProblem
     */
    public function getApiProblem()
    {
        return $this->apiProblem;
    }

    /**
     * Retrieve the content
     *
     * Serializes the composed ApiProblem instance to JSON.
     *
     * @return string
     */
    public function getContent()
    {

        return json_encode($this->apiProblem->toArray(), $this->jsonFlags);
    }

    /**
     * Retrieve headers
     *
     * Proxies to parent class, but then checks if we have an content-type
     * header; if not, sets it, with a value of "application/problem+json".
     *
     * @return \Zend\Http\Headers
     */
    public function getHeaders()
    {
        $headers = parent::getHeaders();
        if (!$headers->has('content-type')) {
            $headers->addHeaderLine('content-type', 'application/problem+json');
        }
        return $headers;
    }

    /**
     * Override reason phrase handling
     *
     * If no corresponding reason phrase is available for the current status
     * code, return "Unknown Error".
     *
     * @return string
     */
    public function getReasonPhrase()
    {
        if (! empty($this->reasonPhrase)) {
            return $this->reasonPhrase;
        }

        if (isset($this->recommendedReasonPhrases[$this->statusCode])) {
            return $this->recommendedReasonPhrases[$this->statusCode];
        }

        return 'Unknown Error';
    }
}

Inside my controller i used:

return new ApiProblemResponse(
  new ApiProblem(ApiProblemResponse::STATUS_CODE_501, 'Example of JSON_PRETTY_PRINT response.')
);

And did the trick:

{
    "type": "http:\/\/www.w3.org\/Protocols\/rfc2616\/rfc2616-sec10.html",
    "title": "Not Implemented",
    "status": 501,
    "detail": "Example of JSON_PRETTY_PRINT response."
}