title: How to generate an azure blob url with SAS signature in nodejs sdk v12?
body: <p>previously (in older sdk like v2) you can generate a sas url (a signed shareable url for a blob) like following : </p>
  
  <pre><code>var azure = require('azure-storage');
  var blobService = azure.createBlobService();
  
  var startDate = new Date();
  var expiryDate = new Date(startDate);
  expiryDate.setMinutes(startDate.getMinutes() + 100);
  startDate.setMinutes(startDate.getMinutes() - 100);
  
  var sharedAccessPolicy = {
    AccessPolicy: {
      Permissions: azure.BlobUtilities.SharedAccessPermissions.READ,
      Start: startDate,
      Expiry: expiryDate
    }
  };
  
  var token = blobService.generateSharedAccessSignature(containerName, blobName, sharedAccessPolicy);
  var sasUrl = blobService.getUrl(containerName, blobName, token);
  </code></pre>
  
  <p>I'm wondering how we can generate that url in sdk v12? 
  I could not find any documentation for Sas URL in v12. </p>
  
  <p>BlobUtilities and getUrl() methods also not available in v12 (in v12 there are separate packages for every module , in my case I'm using require("@azure/storage-blob");) </p>
  
  <p>Thanks.</p>