method Server.prototype.once
#Server.prototype.once(event: string,listener: (...args: any[]) => void,): this#Server.prototype.once(event: "tlsClientError",listener: (err: Error,tlsSocket: TLSSocket,) => void,): this#Server.prototype.once(event: "newSession",listener: (sessionId: Buffer,sessionData: Buffer,callback: () => void,) => void,): this#Server.prototype.once(event: "OCSPRequest",listener: (certificate: Buffer,issuer: Buffer,callback: (err: Error | null,resp: Buffer,) => void,) => void,): this#Server.prototype.once(event: "resumeSession",listener: (sessionId: Buffer,callback: (err: Error | null,sessionData: Buffer | null,) => void,) => void,): this