php 接入扣子的 token获取

本身逻辑只是个api，但是官方不提供php的sdk 扎心了老铁，这下php 狗都不用了，主要麻烦的是如何获取access_token，代码如下

    protected function get_jwt(): string{$header = ['alg' => 'RS256','typ' => 'JWT','kid' => $this->kid];$payload = ['iss' => $this->iss,'aud' => $this->aud,'iat' => time(),'exp' => time() + $this->duration * 60,'jti' => Str::random(32),];$encodedHeader = $this->base64url_encode(json_encode($header));$encodedPayload = $this->base64url_encode(json_encode($payload));$signature = '';$data = $encodedHeader . '.' . $encodedPayload;openssl_sign($data, $signature, Storage::get('private_key.pem'), 'sha256WithRSAEncryption');$encodeSignature = $this->base64url_encode($signature);return $encodedHeader . '.' . $encodedPayload . '.' . $encodeSignature;}private function base64url_encode($data){return rtrim(strtr(base64_encode($data), '+/', '-_'), '=');}