Azure Blob Storage Adapter

An adapter that provides an abstraction layer over the API of the Microsoft Azure Blob cloud storage service.

This adapter is one of the adapters that is meant to be used as a plugin of the Storage Abstraction package. However it can be used standalone as well, see below.

The API of the adapter abstracts away the differences between the API's of cloud storage services. The API only supports the basic, most commonly used cloud service operations such as creating a bucket, storing files and so on.

It is also possible to access all the specific functionality of the cloud service API through the service client of the adapter, see here.

If you are new to the Storage Abstraction library you may want to read this first.

import { Storage, Provider } from "@tweedegolf/storage-abstraction";

const configuration = {
  type: Provider.AZURE,
  accountName: "yourAccount",
  accountKey: "yourKey",
};

const storage = new Storage(configuration);

const result = await storage.listBuckets();

console.log(result);

The Storage class is cloud service agnostic and doesn't know anything about the adapter it uses and adapters are completely interchangeable. It only expects the adapter to have implemented all methods of the IAdapter interface, see the API.

When you create a Storage instance it checks the mandatory provider key in the configuration object and then loads the appropriate adapter module automatically from your node_modules folder using require(). For more information please read this.

Configuration

The configuration object that you pass to the Storage constructor is forwarded to the constructor of the adapter.

The Storage constructor is only interested in the provider key of the configuration object, all other keys are necessary for configuring the adapter.

The Storage constructor expects the configuration to be of type StorageAdapterConfig.

The adapter expects the configuration to be of type AdapterConfig or a type that extends this type.

export interface AdapterConfig {
  bucketName?: string;
  [id: string]: any; // any mandatory or optional key
}

export interface StorageAdapterConfig extends AdapterConfig {
  type: string;
}

The type of the configuration object for this adapter:

export interface AdapterConfigAzure extends AdapterConfig {
  accountName?: string;
  connectionString?: string;
  accountKey?: string;
  sasToken?: string;
  blobDomain?: string;
}

You can omit the protocol of blobDomain. If you set blobDomain to localhost or 127.0.0.1 http is assumed, if you set it to any other value https is assumed. Sometimes you may want to explicitly set the protocol for instance if you are testing with a secure connection to Azurite.

Examples

Examples with configuration object:

const s = new Storage({
  type: Provider.AZURE,
  accountName: "your-account-name",
  accountKey: "your-account-key",
});

const s = new Storage({
  type: Provider.AZURE,
  accountName: "your-account-name",
  accountKey: "your-account-key",
  bucketName: "the-buck"
  maxTries: 3
});

const s = new Storage({
  type: Provider.AZURE,
  accountName: "your-account-name",
  sasToken: "your-sas-token",
  blobDomain: "your-blob-domain", // Defaults to blob.core.windows.net
  bucketName: "the-buck"
});

const s = new Storage({
  type: Provider.AZURE,
  connectionString: "DefaultEndpointsProtocol=http;AccountName=test;AccountKey=test;BlobEndpoint=http://127.0.0.1:10000/test"
});

Same examples with configuration url:

const s = new Storage("azure://your-account-name:your-account-key");

const s = new Storage("azure://your-account-name:your-account-key@the-buck?maxTries=3");

For more information about configuration urls please read this.

Login to Microsoft Azure Blob Storage

There are multiple ways to login to Azure Blob Storage. Microsoft recommends to use passwordless (Microsoft Entra) authorization, for this you need to provide a value for accountName which is the name of your storage account. Then you can either login using the Azure CLI command az login or by setting the following environment variables:

AZURE_TENANT_ID
AZURE_CLIENT_ID
AZURE_CLIENT_SECRET

You can find these values in the Azure Portal, see the documentation on Microsoft website.

Alternately you can login by:

• providing a value for connectionString
• providing a value for both accountName and accountKey
• providing a value for both accountName and sasToken

Note that if you don use a sasToken for authorization you are not authorized to use bucketIsPublic and if you add files to a bucket you will get this error message:

'Can only generate the SAS when the client is initialized with a shared key credential'

This does not mean that the file hasn't been uploaded, it simply means that no public url can been generated for this file.

Azurite

You can your code with Azurite. I would recommend using the commandline version. The VS Code plugin versions has some flaws in my experience.

// connect to Azurite using the builtin account
const config = {
  type: Provider.AZURE,
  bucketName: "test",
  accountName: "devstoreaccount1",
  accountKey: "Eby8vdM02xNOcqFlqUwJPLlmEtlCDXJ1OUzFT50uSRZ6IFsuFq2UVErCz4I6tq/K1SZFPTOtr/KBHBeksoGMGw==",
  blobDomain: "127.0.0.1:10000",
}

[!NOTE] Azurite does not support passwordless login

Standalone

You can also use the adapter standalone, without the need to create a Storage instance:

import { AdapterAzureBlob } from "@tweedegolf/sab-adapter-azure-blob";

const a = new AdapterAzureBlob({
  accountName: "yourAccount",
});
const r = await a.listBuckets();
console.log(r);

API

For a complete description of the Adapter API see this part documentation of the Storage Abstraction package readme.