Method token

packages/google-chat/src/api/index.ts:29–71

()

  private _token: string;

  get token(): Promise<string> {
    return (async () => {
      if (this._token) return this._token;

      const oHeader = { alg: "RS256", typ: "JWT" };
      const tNow = KJUR.jws.IntDate.get("now");
      const tEnd = tNow + this.tokenExpiration;
      const oPayload = {
        iss: this.emailAddress,
        scope: "https://www.googleapis.com/auth/chat.bot",
        aud: "https://oauth2.googleapis.com/token",
        iat: tNow,
        exp: tEnd,
      };

      const sHeader = JSON.stringify(oHeader);
      const sPayload = JSON.stringify(oPayload);
      const sJWT = KJUR.jws.JWS.sign(
        "RS256",
        sHeader,
        sPayload,
        this.privateKey,
      );

      const response = await fetch("https://oauth2.googleapis.com/token", {
        method: "POST",
        headers: {
          "Content-Type": "application/x-www-form-urlencoded",
        },
        body: new URLSearchParams({
          grant_type: "urn:ietf:params:oauth:grant-type:jwt-bearer",
          assertion: sJWT,
        }).toString(),
      });

      // eslint-disable-next-line @typescript-eslint/ban-ts-comment
      // @ts-ignore
      const { access_token } = await response.json();

      this._token = access_token;
      return access_token;
    })();
  }

  private api = async (...args: Parameters<typeof fetch>) => {
    const request = new Request(new Request(...args).clone());