presto-proxy/src/main/java/io/prestosql/proxy/ProxyResource.java/ProxyResource/ProxyResource
class ProxyResource:    @Inject
    public ProxyResource(@ForProxy HttpClient httpClient, JsonWebTokenHandler jwtHandler, ProxyConfig config)
    {
        this.httpClient = requireNonNull(httpClient, "httpClient is null");
        this.jwtHandler = requireNonNull(jwtHandler, "jwtHandler is null");
        this.remoteUri = requireNonNull(config.getUri(), "uri is null");
        this.hmac = hmacSha256(loadSharedSecret(config.getSharedSecretFile()));
    }