Updated Azure SDK version and refactoring

Author: alfonsof

azureblobstoragedownload/README.md

@@ -14,12 +14,12 @@ Download a file from a Blob Storage container in an Azure storage account.
   * Python 3
   * Azure SDKs for Python
 
-* Install the Azure SDKs for Python.
+* You install individual Azure library packages on a per-project basis depending on your needs. It is recommended using Python virtual environments for each project. There is no standalone "SDK" installer for Python.
 
-  Install the latest stable version (supports Python 2.7 and 3.x) via pip:
+* Install the specified python packages.
 
   ```bash
-  pip install azure
+  pip install -r requirements.txt
   ```
 
 ## Using the code
@@ -95,41 +95,39 @@ Download a file from a Blob Storage container in an Azure storage account.
   
     1. Navigate to `Storage Account`.
     2. Select your storage account.
-    3. Select `Access keys` and you can see your Storage account name, connection strings and account keys.
+    3. Select `Access keys` and you can see your Storage account connection string.
 
   The connection string looks like this:
 
-    ```bash
-    DefaultEndpointsProtocol=https;AccountName=<ACCOUNT_NAME>;AccountKey=<ACCOUNT_KEY>;EndpointSuffix=core.windows.net
-    ```
+  ```bash
+  DefaultEndpointsProtocol=https;AccountName=<ACCOUNT_NAME>;AccountKey=<ACCOUNT_KEY>;EndpointSuffix=core.windows.net
+  ```
   
   The application configuration is stored in the `app.cfg` file. The file content is:
 
   ```bash
-  [StorageAuthentication]
-  AccountName=<ACCOUNT_NAME>
-  AccountKey=<ACCOUNT_KEY>
+  [Configuration]
+  StorageAccountConnectionString=<STORAGE_ACCOUNT_CONNECTION_STRING>
   ```
 
-  You must edit the `app.cfg` file and replace the values of:
+  You must edit the `app.cfg` file and replace the value of:
   
-  * `<ACCOUNT_NAME>` by the account name of your storage account.
-  * `<ACCOUNT_KEY>` by the account key of your storage account.
+  * `<STORAGE_ACCOUNT_CONNECTION_STRING>` by the connection string of your storage account.
   
   The application uses this information for accessing your Azure storage account.
 
 * Run the code.
 
-  You must provide 3 parameters:
+  You must provide 3 parameters, replace the values of:
 
-  * `<CONTAINER_NAME>`  = Name of the container
-  * `<BLOB_NAME>`       = Blob name in the container
-  * `<LOCAL_FILE_NAME>` = Local file name
+  * `<CONTAINER_NAME>`  by name of the container.
+  * `<BLOB_NAME>`       by blob name in the container.
+  * `<LOCAL_FILE_NAME>` by local file name.
 
   Run application:
 
   ```bash
-  python blobstoragedownload.py container-example blob-example local-file-example
+  python blobstoragedownload.py <CONTAINER_NAME> <BLOB_NAME> <LOCAL_FILE_NAME>
   ```
 
 * Test the application.

azureblobstoragedownload/app.cfg

@@ -1,3 +1,2 @@
-[StorageAuthentication]
-AccountName=<ACCOUNT_NAME>
-AccountKey=<ACCOUNT_KEY>
+[Configuration]
+StorageAccountConnectionString=<STORAGE_ACCOUNT_CONNECTION_STRING>

azureblobstoragedownload/blobstoragedownload.py

@@ -12,12 +12,12 @@
 import sys
 import os
 import configparser
-from azure.storage.blob import BlockBlobService, PublicAccess
+from azure.storage.blob import BlobServiceClient
 
 
-def loadcfg():
+def load_cfg():
     """
-    Read storage authentication information from a config file
+    Read storage account authentication information from a config file
     and return the values in a dictionary.
     """
     config_file = 'app.cfg'
@@ -28,7 +28,31 @@ def loadcfg():
         print('Config file "' + config_file + '" does not exist')
         sys.exit(1)
 
-    return dict(config.items('StorageAuthentication'))
+    return dict(config.items('Configuration'))
+
+
+def download_blob(storage_account_conn_str, container_name, blob_name, local_file_name):
+    """
+    Download a Blob from a blob storage container.
+    """
+    try:
+        # Create the BlobServiceClient object which will be used to create a blob client
+        blob_service_client = BlobServiceClient.from_connection_string(storage_account_conn_str)
+
+        # Create a blob client using the blob name
+        blob_client = blob_service_client.get_blob_client(container=container_name, blob=blob_name)
+
+        # Download the local file from the Blob container
+        print('Downloading the Blob from the Blob Storage container to the local file ...')
+        with open(local_file_name, "wb") as download_file:
+            download_file.write(blob_client.download_blob().readall())
+        print("\nDownloaded")
+
+    except Exception as e:
+        print("\nError:")
+        print(e)
+
+    return
 
 
 def main():
@@ -49,28 +73,12 @@ def main():
     local_file_name = args[2]
     print('Local file: ' + local_file_name)
 
-    # Read storage authentication information
-    config_dict = loadcfg()
-    cfg_account_name = config_dict['accountname']
-    cfg_account_key = config_dict['accountkey']
-
-    # Create the BlockBlockService that is used to call the Blob service for the storage account
-    block_blob_service = BlockBlobService(account_name=cfg_account_name, account_key=cfg_account_key)
+    # Read storage account authentication information
+    config_dict = load_cfg()
+    cfg_storage_account_conn_str = config_dict['storageaccountconnectionstring']
 
-    try:
-        if block_blob_service.exists(container_name):
-            if block_blob_service.exists(container_name, blob_name):
-                # Download the blob to a local file
-                print('Downloading a Blob from a Blob Storage to a local file ...')
-                block_blob_service.get_blob_to_path(container_name, blob_name, local_file_name)
-                print("\nDownloaded")
-            else:
-                print('\nError: Blob "' + blob_name + '" does NOT exist.')
-        else:
-            print('\nError: Blob Storage container "' + container_name + '" does NOT exist.')
-    except Exception as e:
-        print("\nError:")
-        print(e)
+    # Download a Blob from a blob storage container
+    download_blob(cfg_storage_account_conn_str, container_name, blob_name, local_file_name)
 
     return
 

azureblobstoragedownload/requirements.txt

@@ -0,0 +1 @@
+azure-storage-blob