composer.json

{
    "type": "project",
    "license": "proprietary",
    "require": {
        "php": "^7.2.5",
        "ext-ctype": "*",
        "ext-iconv": "*",
        "sensio/framework-extra-bundle": "^5.1",
        "symfony/asset": "5.0.*",
        "symfony/console": "5.0.*",
        "symfony/dotenv": "5.0.*",
        "symfony/expression-language": "5.0.*",
        "symfony/flex": "^1.3.1",
        "symfony/form": "5.0.*",
        "symfony/framework-bundle": "5.0.*",
        "symfony/http-client": "5.0.*",
        "symfony/intl": "5.0.*",
        "symfony/mailer": "5.0.*",
        "symfony/monolog-bundle": "^3.1",
        "symfony/notifier": "5.0.*",
        "symfony/orm-pack": "*",
        "symfony/process": "5.0.*",
        "symfony/property-info": "5.0.*",
        "symfony/security-bundle": "5.0.*",
        "symfony/serializer-pack": "^1.0",
        "symfony/string": "5.0.*",
        "symfony/translation": "5.0.*",
        "symfony/twig-pack": "*",
        "symfony/validator": "5.0.*",
        "symfony/web-link": "5.0.*",
        "symfony/yaml": "5.0.*"
    },
    "require-dev": {
        "symfony/debug-pack": "*",
        "symfony/maker-bundle": "^1.0",
        "symfony/profiler-pack": "*",
        "symfony/test-pack": "*"
    },
    "config": {
        "preferred-install": {
            "*": "dist"
        },
        "sort-packages": true
    },
    "autoload": {
        "psr-4": {
            "App\\": "src/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "App\\Tests\\": "tests/"
        }
    },
    "replace": {
        "paragonie/random_compat": "2.*",
        "symfony/polyfill-ctype": "*",
        "symfony/polyfill-iconv": "*",
        "symfony/polyfill-php72": "*",
        "symfony/polyfill-php71": "*",
        "symfony/polyfill-php70": "*",
        "symfony/polyfill-php56": "*"
    },
    "scripts": {
        "auto-scripts": {
            "cache:clear": "symfony-cmd",
            "assets:install %PUBLIC_DIR%": "symfony-cmd"
        },
        "post-install-cmd": [
            "@auto-scripts"
        ],
        "post-update-cmd": [
            "@auto-scripts"
        ]
    },
    "conflict": {
        "symfony/symfony": "*"
    },
    "extra": {
        "symfony": {
            "allow-contrib": false,
            "require": "5.0.*"
        }
    }
}

data

{
    "success": true,
    "result": [
        {
            "Name": "Project A",
            "isonsale": "1"
        },
        {
            "Name": "Project B",
            "isonsale": "1"
        },
        {
            "Name": "Project C",
            "isonsale": "0"
        }
     ]
}

Project.php

<?php

namespace App\Model;

use Symfony\Component\Serializer\Annotation\SerializedName;

class Project {

    /**
     * @SerializedName("Name")
     * @var string
     */
    private $title;

    /**
     * @SerializedName("isonsale")
     * @var string
     */
    private $sale;

    /**
     * @param string $title
     */
    public function setTitle(string $title): void
    {
        $this->title = $title;
    }

    /**
     * @param string $sale
     */
    public function setSale(string $sale): void
    {
        $this->sale = $sale;
    }
}

ProjectCollection.php

<?php

namespace App\Model;

use Symfony\Component\Serializer\Annotation\SerializedName;

class ProjectCollection
{
    /**
     * @SerializedName("result")
     * @var Project[]
     */
    private $result;

    /**
     * @return Project[]|null
     */
    public function getResult(): ?array
    {
        return $this->result;
    }

    /**
     * @param Project[] $results
     */
    public function setResult(array $result)
    {
        $this->result = $result;
    }
}

TestDeserializeController.php

<?php

namespace App\Controller;

use App\Model\ProjectCollection;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Routing\Annotation\Route;
use Symfony\Component\HttpClient\HttpClient;
use Symfony\Component\Serializer\Encoder\JsonEncoder;
use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
use Symfony\Component\Serializer\Serializer;
use Symfony\Component\Serializer\SerializerInterface;

class TestDeserializeController extends AbstractController {
    /**
     * @Route("/test/deserialize", name="test_deserialize")
     */
    public function index(SerializerInterface $serializer) {

        $projects = [];

        $client = HttpClient::create();

        $response = $client->request('GET', 'https://gist.github.com/parijke/05ac5d4332c1633ef23be25027a24965/raw/638941a29c0aa4c4d271e29b142e0472f88496bd/data');

        $collection = $serializer->deserialize($response->getContent(), ProjectCollection::class, 'json');

        if (!empty($collection->getResult()))
        {
            foreach ($collection->getResult() as $project)
            {
                $projects[] = $project;
            }
        }

        dd($projects);
    }


}