OAuth2\OAuth2::grantAccessTokenAuthCode PHP Method

    protected function grantAccessTokenAuthCode(IOAuth2Client $client, array $input)
    {
        if (!$this->storage instanceof IOAuth2GrantCode) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_UNSUPPORTED_GRANT_TYPE);
        }
        if (!$input["code"]) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_INVALID_REQUEST, 'Missing parameter. "code" is required');
        }
        if ($this->getVariable(self::CONFIG_ENFORCE_INPUT_REDIRECT) && !$input["redirect_uri"]) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_INVALID_REQUEST, "The redirect URI parameter is required.");
        }
        $authCode = $this->storage->getAuthCode($input["code"]);
        // Check the code exists
        if ($authCode === null || $client->getPublicId() !== $authCode->getClientId()) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_INVALID_GRANT, "Code doesn't exist or is invalid for the client");
        }
        // Validate the redirect URI. If a redirect URI has been provided on input, it must be validated
        if ($input["redirect_uri"] && !$this->validateRedirectUri($input["redirect_uri"], $authCode->getRedirectUri())) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_REDIRECT_URI_MISMATCH, "The redirect URI is missing or do not match");
        }
        if ($authCode->hasExpired()) {
            throw new OAuth2ServerException(self::HTTP_BAD_REQUEST, self::ERROR_INVALID_GRANT, "The authorization code has expired");
        }
        $this->usedAuthCode = $authCode;
        return array('scope' => $authCode->getScope(), 'data' => $authCode->getData());
    }