PHPUnit: Asserting JSON Paths

CanAssertJsonPaths.php

<?php

namespace Tests\Http;

/**
 *
 * Use this trait in your Laravel/Lumen TestCase class
 * to get the assertJSON... functionality out of the box
 *
 * Trait CanAssertJsonPaths
 * @package Tests\Http
 */
trait CanAssertJsonPaths
{

    protected static $uriCachedData = [];

    /**
     * Visit the given URI with a JSON request.
     *
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param array $data
     * @param array $headers
     * @return $this
     */
    public function cachedJsonGet(string $uri, array $data = [], array $headers = [])
    {
        if (empty(static::$uriCachedData[$uri])) {
            $this->json('GET', $uri, $data, $headers);
            static::$uriCachedData[$uri] = $this->response;
            return $this;
        } else {
            $this->response = static::$uriCachedData[$uri];
            return $this;
        }
    }

    public function clearCacheForUri(string $uri)
    {
        if(!empty(static::$uriCachedData[$uri])){
            unset(static::$uriCachedData[$uri]);
        }
    }

    /**
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param bool $cached
     * @return false|string
     */
    protected function getContentResponseFromUri(string $uri, bool $cached = false)
    {
        if ($cached) {
            $response = $this->cachedJsonGet($uri)->response->getContent();
        } else {
            $response = $this->json('GET', $uri)->response->getContent();
        }
        return $response;
    }

    /**
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @param bool $cached - should endpoint result be cached across tests
     * @throws \JsonException
     */
    protected function assertJsonPathExists(string $uri, string $jsonPath, bool $cached = false)
    {
        $jsonPath = $this->clearJSONPathAndChangeItToPHPSyntax($jsonPath);
        $content = $this->getContentResponseFromUri($uri, $cached);
        $contentDecoded = json_decode($content, false);
        $pathToCheck = '$contentDecoded->' . $jsonPath;
        $isset = eval('return isset(' . $pathToCheck . ');');
        $this->assertTrue($isset, "Error in endpoint: {$uri} \n {$pathToCheck} path doesn't exist in JSON");
    }

    /**
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @param bool $cached - should endpoint result be cached across tests
     * @throws \JsonException
     */
    protected function assertJsonPathDoesntExist(string $uri, string $jsonPath, bool $cached = false)
    {
        $jsonPath = $this->clearJSONPathAndChangeItToPHPSyntax($jsonPath);
        $content = $this->getContentResponseFromUri($uri, $cached);
        $contentDecoded = json_decode($content, false);
        $pathToCheck = '$contentDecoded->' . $jsonPath;
        $isNotSet = eval('return !isset(' . $pathToCheck . ');');
        $valueOfTheKey = "";
        if (!$isNotSet) {
            $valueOfTheKey = eval('return json_encode(' . $pathToCheck . ');');
        }
        $this->assertTrue($isNotSet,
            "Error in endpoint: {$uri} \n{$pathToCheck}path exists in JSON, value is: {$valueOfTheKey}");
    }

    /**
     * Is empty means: [], null, 0, "", false, !isset()
     *
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @param bool $cached - should endpoint result be cached across tests in class (first invoke is stored in cache
     *     and served to the rest invokes)
     */
    protected function assertJsonPathIsEmpty(string $uri, string $jsonPath, bool $cached = false)
    {
        $jsonPath = $this->clearJSONPathAndChangeItToPHPSyntax($jsonPath);
        $content = $this->getContentResponseFromUri($uri, $cached);
        $contentDecoded = json_decode($content, false);
        $pathToCheck = '$contentDecoded->' . $jsonPath;
        $empty = eval('return empty(' . $pathToCheck . ');');
        $valueOfTheKey = "";
        if (!$empty) {
            $valueOfTheKey = eval('return json_encode(' . $pathToCheck . ');');
        }
        $this->assertTrue($empty,
            "Error in endpoint: {$uri} \n{$pathToCheck} path is not empty, so does not equal: [], null, 0, \"\", false, or !isset() \nValue of the key: {$valueOfTheKey}");
    }


    /**
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @param string|int|float $expectedValue
     * @param bool $cached - should endpoint result be cached across tests in class (first invoke is stored in cache
     *     and served to the rest invokes)
     * @throws \JsonException
     */
    protected function assertJsonPathHasValue(string $uri, string $jsonPath, $expectedValue, bool $cached = false)
    {
        $this->assertJsonPathExists($uri, $jsonPath, $cached);
        $content = $this->getContentResponseFromUri($uri, $cached);
        $contentDecoded = json_decode($content, false);
        $jsonPath = $this->clearJSONPathAndChangeItToPHPSyntax($jsonPath);
        $pathToCheck = '$contentDecoded->' . $jsonPath;
        $value = eval('return ' . $pathToCheck . ';');
        if (is_string($expectedValue) && preg_replace("#\s+#", "", $expectedValue) === '[]') {
            $this->assertTrue(is_array($value), "{$pathToCheck} path is not an array");
        } else {
            $this->assertEquals($expectedValue, $value,
                "Error in endpoint: {$uri} \n{$pathToCheck} path doesn't have expected value: {$expectedValue}, instead it equals: {$value}");
        }
    }

    /**
     * @param string $uri - endpoint uri ex. '/api/user/1'
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @param string $expectedRegex - ex. '#\d+#' ( # is regex delimiter in the example )
     * @param bool $cached - should endpoint result be cached across tests in class (first invoke is stored in cache
     *     and served to the rest invokes)
     * @throws \JsonException
     */
    protected function assertJsonPathHasRegex(string $uri, string $jsonPath, string $expectedRegex, bool $cached = false)
    {
        $this->assertJsonPathExists($uri, $jsonPath, $cached);
        $content = $this->getContentResponseFromUri($uri, $cached);
        $contentDecoded = json_decode($content, false);
        $jsonPath = $this->clearJSONPathAndChangeItToPHPSyntax($jsonPath);
        $pathToCheck = '$contentDecoded->' . $jsonPath;
        $value = eval('return ' . $pathToCheck . ';');
        if (preg_replace("#\s+#", "", $expectedRegex) === '[]') {
            $this->assertTrue(is_array($value), "$pathToCheck path is not an array");
        } else {
            $this->assertRegExp($expectedRegex, strval($value),
                "Error in endpoint: {$uri} \n$pathToCheck path doesn't have expected value: {$expectedRegex}, instead it equals: {$value}");
        }
    }

    /**
     * @param string $jsonPath - ex. 'data.users[1].name'
     * @return string
     */
    private function clearJSONPathAndChangeItToPHPSyntax(string $jsonPath): string
    {
        // clear from JSON not-allowed chars
        $jsonPath = preg_replace('#[^a-zA-Z0-9\"\]\[._ -]+#', '', $jsonPath);
        // replace 'data.user[1].name' to 'data->user[1]->name' which is valid PHP syntax
        $jsonPath = str_replace('.', '->', $jsonPath);
        return $jsonPath;
    }

}

CatalogEndpointTest.php

<?php

namespace Tests\Http;

class CatalogEndpointTest extends TestCase
{
    public function testCatalogBrowser() 
    {
        $uri = '/api/v1/catalog/browser?category_slug=some-slug';
        
        $this->assertJsonPathHasValue($uri, 'data.items[0].product.alias', 'Training');
        $this->assertJsonPathHasValue($uri, 'data.items[1].product.alias', 'Training');
        
        $this->assertJsonPathHasRegex($uri, 'data.items[0].product.alias.id', self::UUID_REGEX, true);
     }
}

TestCase.php

<?php

namespace Tests\Http;

abstract class TestCase extends \Laravel\Lumen\Testing\TestCase
{
    use CanAssertJsonPaths;
    // ...
    // ...
    
    const ID_REGEXP = "#[A-Z0-9-]{36}#";
    const DATE_TIME_REGEX = "#\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}#";
    const CURRENCY_CODE_REGEXP = "#[A-Z]{2,5}#";
    const ALIAS_REGEX = '#[A-Za-z0-9-]{3,}#si';
    const TITLE_REGEX = "#\w{3,}#";
    const UUID_REGEX =  "#[A-Z0-9-]{20,}#";
    const SLUG_REGEX = '#[a-zA-Z0-9_-]+#';
    const PRODUCT_CODE_REGEX = "/[A-Za-z0-9#-_]{2,}.*?/";
    const FLOAT_REGEX = '#^[0-9.]{1,}$#';
    const INT_REGEX = '#^[0-9]{1,}$#';
    
}