# Azure Blob Storage

> Source: https://docs.clonepartner.com/connectors/azure-blob/

<!-- sources: src/connectors/azure-blob.ts, src/connectors/csv-options.ts, references/envoy/connectors.md -->

# Azure Blob Storage

The `azure-blob` connector reads, writes, and manages blobs in an Azure Storage account, with optional parsing of blob content as JSON, YAML, or CSV.

## When to use it

Use `azure-blob` when task data lives in Azure Storage containers — exported files to ingest, or output files to publish. For AWS S3, Cloudflare R2, or other S3-compatible stores, use the [S3 and R2](/connectors/s3/) connector instead.

## Configuration

| Key | Type | Required | Default | Description |
|---|---|---|---|---|
| `connection_string` | string | Yes | — | Azure Storage account connection string (stored as a secret) |
| `container` | string | Yes | — | Default blob container name |

Every method accepts a `container` argument that overrides the default container for that call.

## Methods

| Method | Arguments | Returns | Behavior |
|---|---|---|---|
| `list` | `prefix`, `container` | array | Streams one object per blob (`name`, `size`, `contentType`, `lastModified`) matching the prefix |
| `read` | `blob` (required), `format`, `container`, `escape`, `from_record`, `delimiter`, `separator` | array | Reads a blob and parses it: `text` (default), `json`, `yaml`, or `csv`; CSV is streamed record by record |
| `write` | `blob` (required), `data` (required), `format`, `container`, `content_type` | object | Serializes `data` as `text` (default), `json`, `yaml`, or `csv` and uploads it to the blob |
| `delete` | `blob` (required), `container` | void | Deletes the blob |
| `upload` | `blob` (required), `body` (required), `content_type`, `metadata`, `container` | object | Uploads raw bytes; `body` is a string, or base64 for binary content |
| `head` | `blob` (required), `container` | object | Returns blob metadata without downloading the content |
| `download` | `blob` (required), `encoding`, `container` | object | Downloads blob content as `text` (default) or `base64` |

## Example

```yaml
name: import_exported_orders
connectors:
  source:
    type: azure-blob
steps:
  - name: read_orders
    type: call_method
    config: |
      {
        "connector": "source",
        "method": "read",
        "args": { "blob": "exports/orders.csv", "format": "csv" }
      }
```

The matching `connectors.yaml` entry for CLI runs:

```yaml
source:
  type: azure-blob
  config:
    connection_string: ${AZURE_STORAGE_CONNECTION_STRING}
    container: envoy-data
```

## Behavior notes

- `list` and CSV-format `read` return async iterators — downstream steps receive records with backpressure instead of a buffered array.
- CSV parsing reads the header row as column names, skips empty lines, and coerces the literal cell values `NULL` and `null` to JSON `null`.
- `delimiter` accepts the named values `tab` (or `\t`), `comma`, `semicolon`, and `pipe` as well as a literal character; `separator` is an alias. The CSV escape character defaults to a double quote.
- `from_record` resumes CSV parsing from a specific record number, which supports restartable imports.
- The connector supports file uploads from the connector editor (any extension).
- The connection test validates credentials, checks that the configured container exists, lists one page of blobs, and runs a write-and-delete probe.

## Related

- [Connectors overview](/connectors/) — all compiled connector types
- [S3 and R2](/connectors/s3/) — the S3-compatible equivalent
- [Reading and writing data](/building/reading-and-writing-data/) — calling connector methods from steps