Provider.php

<?php

namespace SocialiteProviders\Instagram;

use SocialiteProviders\Manager\OAuth2\User;
use Laravel\Socialite\Two\ProviderInterface;
use SocialiteProviders\Manager\OAuth2\AbstractProvider;

class Provider extends AbstractProvider implements ProviderInterface
{
    /**
     * Unique Provider Identifier.
     */
    const IDENTIFIER = 'INSTAGRAM';

    /**
     * {@inheritdoc}
     */
    protected $scopeSeparator = ' ';

    /**
     * {@inheritdoc}
     */
    protected $scopes = ['user_profile'];

    /**
     * @var string
     */
    protected $fields = 'username,account_type,media_count,media';

    /**
     * {@inheritdoc}
     */
    protected function getAuthUrl($state)
    {
        return $this->buildAuthUrlFromBase(
            'https://api.instagram.com/oauth/authorize',
            $state
        );
    }

    /**
     * {@inheritdoc}
     */
    protected function getTokenUrl()
    {
        return 'https://api.instagram.com/oauth/access_token';
    }

    /**
     * @return string
     */
    protected function getLongTermTokenUrl()
    {
        return 'https://graph.instagram.com/access_token';
    }

    /**
     * @return string
     */
    protected function getRefreshLongTermTokenUrl()
    {
        return 'https://graph.instagram.com/refresh_access_token';
    }

    /**
     * {@inheritdoc}
     */
    protected function getUserByToken($token)
    {
        $query = [
            'access_token' => $token,
            'fields' => $this->fields,
        ];

        $response = $this->getHttpClient()->get(
            'https://graph.instagram.com/me', [
            'query' => $query,
            'headers' => [
                'Accept' => 'application/json',
            ],
        ]);

        return json_decode($response->getBody()->getContents(), true);
    }

    /**
     * @param $token
     * @return mixed
     */
    protected function getMediaByToken($token)
    {
        $query = [
            'access_token' => $token,
            'fields' => $this->fields,
        ];

        $response = $this->getHttpClient()->get(
            'https://graph.instagram.com/me/media', [
            'query' => $query,
            'headers' => [
                'Accept' => 'application/json',
            ],
        ]);

        return json_decode($response->getBody()->getContents(), true);
    }

    /**
     * Get Media from a known access token.
     *
     * @param  string  $token
     * @return \Laravel\Socialite\Two\User
     */
    public function mediaFromToken($token)
    {
        return $this->getMediaByToken($token);
    }

    /**
     * {@inheritdoc}
     */
    protected function mapUserToObject(array $user)
    {
        return (new User())->setRaw($user)->map(
            [
                'id' => $user['id'],
                'nickname' => $user['username'],
                'name' => $user['username'],
                'account_type' => $user['account_type'],
                'avatar' => null,
            ]
        );
    }

    /**
     * {@inheritdoc}
     */
    public function getAccessToken($code)
    {
        $response = $this->getHttpClient()->post($this->getTokenUrl(), [
            'form_params' => $this->getTokenFields($code),
        ]);

        $this->credentialsResponseBody = json_decode($response->getBody(), true);

        return $this->parseAccessToken($response->getBody());
    }

    /**
     * @param string $token
     * @return mixed
     */
    public function refreshLongTermAccessToken(string $token) {
        $query = [
            'grant_type' => 'ig_refresh_token',
            'access_token' => $token,
        ];

        $response = $this->getHttpClient()->get(
            $this->getRefreshLongTermTokenUrl(),
            [
                'query' => $query,
                'headers' => [
                    'Accept' => 'application/json',
                ],
            ]
        );

        return json_decode($response->getBody()->getContents(), true);
    }

    /**
     * @param string $oldToken
     * @return mixed
     */
    public function getLongTermAccessToken(string $oldToken)
    {
        $query = array_merge(
            parent::getTokenFields(null),
            [
                'grant_type' => 'ig_exchange_token',
                'access_token' => $oldToken,
            ]
        );

        $response = $this->getHttpClient()->get(
            $this->getLongTermTokenUrl(),
            [
                'query' => $query,
                'headers' => [
                    'Accept' => 'application/json',
                ],
            ]
        );

        return json_decode($response->getBody()->getContents(), true);
    }

    /**
     * @param $fields
     * @return $this
     */
    public function setFields($fields)
    {
        if (is_array($fields)) {
            $fields = implode(',', $fields);
        }

        $this->fields = $fields;

        return $this;
    }

    /**
     * {@inheritdoc}
     */
    protected function getTokenFields($code)
    {
        return array_merge(parent::getTokenFields($code), [
            'grant_type' => 'authorization_code',
        ]);
    }
}