in public/utils/connStringHelper.ts [30:48]
function generateSasToken(
resourceUri: string,
signingKey: string,
policyName: string,
expiresInMins: number
): string {
resourceUri = encodeURIComponent(resourceUri);
const expiresInSeconds = Math.ceil(Date.now() / 1000 + expiresInMins * 60);
const toSign = resourceUri + "\n" + expiresInSeconds;
// Use the crypto module to create the hmac.
const hmac = crypto.createHmac("sha256", Buffer.from(signingKey, "base64"));
hmac.update(toSign);
const base64UriEncoded = encodeURIComponent(hmac.digest("base64"));
// Construct authorization string.
return `SharedAccessSignature sr=${resourceUri}&sig=${base64UriEncoded}&se=${expiresInSeconds}&skn=${policyName}`;
}