Azure Storage Account

Azure Blob Storage is a cloud storage solution for data storage and retrieval that is highly available, secure, durable, and scalable. cshelve can be configured to use Azure Blob Storage as a provider for storing and retrieving data.

Installation

To install the cshelve package with Azure Blob support, run the following command:

pip install cshelve[azure-blob]

Configuration Options

The following table lists the configuration options available for the Azure Blob Storage provider:

Scope	Option	Description	Required
default	account_url	URL of the Azure Blob Storage account	No
default	auth_type	Authentication method: access_key, connection_string, passwordless, or anonymous.	Yes
default	container_name	Container name in the Azure storage account	Yes
logging	http	Enable HTTP logging	No
logging	credentials	Enable logging for credential operations	No

Permissions

Flag	Description	Permissions Needed
r	Open existing container for read-only access.	Storage Blob Data Reader
w	Open existing container for read/write access.	Storage Blob Data Contributor
c	Open container with read/write access, creating it if necessary.	Storage Blob Data Contributor

Logging Configuration

The logging configuration allows enabling HTTP logging for blob storage operations and credential operations. To view logging output, you must configure the logging handler as explained in the Azure SDK logging documentation.

Example: Passwordless Authentication

cat passwordless.ini
[default]
provider        = azure-blob
account_url     = https://myaccount.blob.core.windows.net
auth_type       = passwordless
container_name  = mycontainer

[logging]
http            = true

import cshelve
import sys
import logging

logger = logging.getLogger()
logger.setLevel(logging.DEBUG)
handler = logging.StreamHandler(stream=sys.stdout)
logger.addHandler(handler)

with cshelve.open('passwordless.ini') as db:
    ...

Example: Access Key Authentication

cat access-key.ini
[default]
provider        = azure-blob
account_url     = https://myaccount.blob.core.windows.net
auth_type       = access_key
# Environment variables: AZURE_STORAGE_ACCESS_KEY
container_name  = container
key_id          = AZURE_STORAGE_KEY_ID
key_secret      = AZURE_STORAGE_KEY_SECRET

Example: Connection String Authentication

cat connection-string.ini
[default]
provider        = azure-blob
auth_type       = connection_string
environment_key = AZURE_STORAGE_CONNECTION_STRING
container_name  = test-connection-string

Example: Anonymous Authentication

cat anonymous.ini
[default]
provider        = azure-blob
account_url     = https://myaccount.blob.core.windows.net
auth_type       = anonymous
container_name  = public-container

Configure the BlobServiceClient

Behind the scenes, this provider uses the BlobServiceClient.

import cshelve

provider_params = {
    'secondary_hostname': 'https://secondary.blob.core.windows.net',
    'max_block_size': 4 * 1024 * 1024,  # 4 MB
    'use_byte_buffer': True
}

with cshelve.open('azure-blob.ini', provider_params=provider_params) as db:
    ...