@fragment-dev/node-client/dist/esm/src/getToken.js

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const b64 = (str) => Buffer.from(str).toString("base64");
// Refresh the token 2 minutes before it expires
const EXPIRY_TIME_SKEW = 120;
export const getToken = async ({ clientId, secret, scope, authUrl, }) => {
    if (!authUrl.endsWith("oauth2/token")) {
        throw new Error(
        // common error due to copy-paste.
        "The authUrl passed to createFragmentClient must end in /oauth2/token");
    }
    // encode the client id and secret
    const auth = b64(`${clientId}:${secret}`);
    // create the request body
    const data = new URLSearchParams();
    data.append("grant_type", "client_credentials");
    data.append("scope", scope);
    data.append("client_id", clientId);
    // retrieve the token
    const response = await fetch(authUrl, {
        body: data,
        method: "POST",
        headers: {
            "Content-Type": "application/x-www-form-urlencoded",
            Authorization: `Basic ${auth}`,
            Accept: "*/*",
        },
    });
    const json = await response.json();
    if (!(json.access_token && typeof json.access_token === "string")) {
        throw new Error("Didn't get an access token from OAuth token endpoint");
    }
    if (!(json.expires_in && typeof json.expires_in === "number")) {
        throw new Error("Didn't get an expiration from OAuth token endpoint");
    }
    const expiry_time = new Date(new Date().getTime() + (json.expires_in - EXPIRY_TIME_SKEW) * 1000);
    const access_token = json.access_token;
    return { access_token, expiry_time };
};