Azure Blob Storage

Installation

npm install @hot-updater/azure --save-dev

The Azure SDKs the package uses require Node.js 22 or later.

For a deployed server, install the package as a runtime dependency instead of a development dependency.

Setup

For a complete provider deployment, follow the Azure setup. For an existing storage account or a custom server, use the storage configuration below; you do not need to provision the provider's database and server to use this adapter. Create the container first: the adapter does not create it.

Configuration

import type { TokenCredential } from "@azure/core-auth";
import type { StorageSharedKeyCredential } from "@azure/storage-blob";

type AzureBlobStorageConfig = (
  | { connectionString: string }
  | {
      accountUrl: string; // https://<account>.blob.core.windows.net
      credential: StorageSharedKeyCredential | TokenCredential;
    }
) & {
  containerName: string; // The Blob container that keeps the bundles
  basePath?: string; // Optional base path within the container
  getDownloadUrl?: StorageAdapter["getDownloadUrl"]; // Optional, such as a CDN's URL
};

Without getDownloadUrl, devices download each bundle through a read-only SAS URL that expires after an hour. The adapter signs it with the account key when the connection has one: a connection string, or a StorageSharedKeyCredential. With a Microsoft Entra TokenCredential, such as DefaultAzureCredential from @azure/identity, it signs with a user delegation key, which needs the identity's Storage Blob Delegator role besides read and write access to the container's blobs. A SAS connection string can upload, but it cannot sign download URLs: pass getDownloadUrl with one.

Environment variables

HOT_UPDATER_AZURE_STORAGE_CONNECTION_STRING=DefaultEndpointsProtocol=https;AccountName=...

Read the connection string with az storage account show-connection-string --name <account> --resource-group <group>. Keep it out of the app bundle and exclude local environment files from Git.

Usage

import { existsSync } from "node:fs";
import { azureBlobStorage } from "@hot-updater/azure"; 
import { defineConfig } from "hot-updater";

if (existsSync(".env.hotupdater")) {
  process.loadEnvFile(".env.hotupdater");
}

export default defineConfig({
  // ... build, database, plugins, and updateStrategy
  storage: azureBlobStorage({ 
    connectionString: process.env.HOT_UPDATER_AZURE_STORAGE_CONNECTION_STRING!, 
    containerName: "hot-updater", 
  }), 
});

Protocol

azblob://container/encoded/key

For example, azblob://hot-updater/releases/1.0.0/bundle%20ios.zip is stored in the storageUri field. Keys retain their slash hierarchy and encode each segment.

Capabilities

azureBlobStorage buffers each upload in memory and streams each download. It also implements download URL generation, existence checks, exact deletion, listing below a prefix, and batched deletion of exact keys.