Typescript(Javascript): twitch client credentials flow using simple-oauth2

twitch-client-credentials-flow.ts

// https://github.com/lelylan/simple-oauth2
// https://dev.twitch.tv/docs/authentication/getting-tokens-oauth/#oauth-client-credentials-flow
async function getAccessToken(): Promise<AccessToken | null> {
  const client = new ClientCredentials({
    client: {
      id: "client-id",
      secret: "client-secret",
    },
    auth: {
      tokenHost: "https://id.twitch.tv",
      tokenPath: "/oauth2/token",
    },
    options: {
      authorizationMethod: "body",
    },
  });
  try {
    return await client.getToken({
      scope: ["<scope>"],
    });
  } catch (error: any) {
    console.log("Access Token error", error.message);
    return null;
  }
}

Example output

AccessToken {
  token: {
    access_token: 'ftc4q7wswutgq2i8klewgh2v37asdf',
    expires_in: 5218099,
    scope: [ 'chat:read', 'chat:edit' ],
    token_type: 'bearer',
    expires_at: 2022-05-20T00:16:20.494Z
  }
}