# Azure Storage Blob TS

> Azure Blob Storage JavaScript/TypeScript SDK (@azure/storage-blob) for blob operations. Use for uploading, downloading, listing, and managing blobs and containers.

- Skill: `ranbot-ai/azure-storage-blob-ts` (Agent Skill)
- Install (CLI): `npx skillmds add ranbot-ai/azure-storage-blob-ts`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ranbot-ai/azure-storage-blob-ts/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- Author: ranbot-ai (https://skillmd.com/u/ranbot-ai)
- Updated: 2026-09-08
- Page: https://skillmd.com/skills/ranbot-ai/azure-storage-blob-ts

---



# @azure/storage-blob (TypeScript/JavaScript)

SDK for Azure Blob Storage operations — upload, download, list, and manage blobs and containers.

## Installation

```bash
npm install @azure/storage-blob @azure/identity
```

**Current Version**: 12.x  
**Node.js**: >= 18.0.0

## Environment Variables

```bash
AZURE_STORAGE_ACCOUNT_NAME=<account-name>
AZURE_STORAGE_ACCOUNT_KEY=<account-key>
# OR connection string
AZURE_STORAGE_CONNECTION_STRING=DefaultEndpointsProtocol=https;AccountName=...
```

## Authentication

### DefaultAzureCredential (Recommended)

```typescript
import { BlobServiceClient } from "@azure/storage-blob";
import { DefaultAzureCredential } from "@azure/identity";

const accountName = process.env.AZURE_STORAGE_ACCOUNT_NAME!;
const client = new BlobServiceClient(
  `https://${accountName}.blob.core.windows.net`,
  new DefaultAzureCredential()
);
```

### Connection String

```typescript
import { BlobServiceClient } from "@azure/storage-blob";

const client = BlobServiceClient.fromConnectionString(
  process.env.AZURE_STORAGE_CONNECTION_STRING!
);
```

### StorageSharedKeyCredential (Node.js only)

```typescript
import { BlobServiceClient, StorageSharedKeyCredential } from "@azure/storage-blob";

const accountName = process.env.AZURE_STORAGE_ACCOUNT_NAME!;
const accountKey = process.env.AZURE_STORAGE_ACCOUNT_KEY!;

const sharedKeyCredential = new StorageSharedKeyCredential(accountName, accountKey);
const client = new BlobServiceClient(
  `https://${accountName}.blob.core.windows.net`,
  sharedKeyCredential
);
```

### SAS Token

```typescript
import { BlobServiceClient } from "@azure/storage-blob";

const accountName = process.env.AZURE_STORAGE_ACCOUNT_NAME!;
const sasToken = process.env.AZURE_STORAGE_SAS_TOKEN!; // starts with "?"

const client = new BlobServiceClient(
  `https://${accountName}.blob.core.windows.net${sasToken}`
);
```

## Client Hierarchy

```
BlobServiceClient (account level)
└── ContainerClient (container level)
    └── BlobClient (blob level)
        ├── BlockBlobClient (block blobs - most common)
        ├── AppendBlobClient (append-only blobs)
        └── PageBlobClient (page blobs - VHDs)
```

## Container Operations

### Create Container

```typescript
const containerClient = client.getContainerClient("my-container");
await containerClient.create();

// Or create if not exists
await containerClient.createIfNotExists();
```

### List Containers

```typescript
for await (const container of client.listContainers()) {
  console.log(container.name);
}

// With prefix filter
for await (const container of client.listContainers({ prefix: "logs-" })) {
  console.log(container.name);
}
```

### Delete Container

```typescript
await containerClient.delete();
// Or delete if exists
await containerClient.deleteIfExists();
```

## Blob Operations

### Upload Blob (Simple)

```typescript
const containerClient = client.getContainerClient("my-container");
const blockBlobClient = containerClient.getBlockBlobClient("my-file.txt");

// Upload string
await blockBlobClient.upload("Hello, World!", 13);

// Upload Buffer
const buffer = Buffer.from("Hello, World!");
await blockBlobClient.upload(buffer, buffer.length);
```

### Upload from File (Node.js only)

```typescript
const blockBlobClient = containerClient.getBlockBlobClient("uploaded-file.txt");
await blockBlobClient.uploadFile("/path/to/local/file.txt");
```

### Upload from Stream (Node.js only)

```typescript
import * as fs from "fs";

const blockBlobClient = containerClient.getBlockBlobClient("streamed-file.txt");
const readStream = fs.createReadStream("/path/to/local/file.txt");

await blockBlobClient.uploadStream(readStream, 4 * 1024 * 1024, 5, {
  // bufferSize: 4MB, maxConcurrency: 5
  onProgress: (progress) => console.log(`Uploaded ${progress.loadedBytes} bytes`),
});
```

### Upload from Browser

```typescript
const blockBlobClient = containerClient.getBlockBlobClient("browser-upload.txt");

// From File input
const fileInput = document.getElementById("fileInput") as HTMLInputElement;
const file = fileInput.files![0];
await blockBlobClient.uploadData(file);

// From Blob/ArrayBuffer
const arrayBuffer = new ArrayBuffer(1024);
await blockBlobClient.uploadData(arrayBuffer);
```

### Download Blob

```typescript
const blobClient = containerClient.getBlobClient("my-file.txt");
const downloadResponse = await blobClient.download();

// Read as string (browser & Node.js)
const downloaded = await streamToText(downloadResponse.readableStreamBody!);

async function streamToText(readable: NodeJS.ReadableStream): Promise<string> {
  const chunks: Buffer[] = [];
  for await (const chunk of readable) {
    chunks.push(Buffer.from(chunk));
  }
  return Buffer.concat(chunks).toString("utf-8");
}
```

### Download to File (Node.js only)

```typescript
const blockBlobClient = containerClient.getBlockBlobClient("my-file.txt");
await blockBlobClient.downloadToFile("/path/to/local/destination.txt");
```

### Download to Buffer (Node.js only)

```ty