Add support for copying blobs between containers

Fixes #23

Author: JoeDupuis

lib/azure_blob/client.rb

@@ -77,16 +77,22 @@ def get_blob(key, options = {})
       Http.new(uri, headers, signer:).get
     end
 
-    # Copy a blob
+    # Copy a blob between containers or within the same container
     #
     # Calls to {Copy Blob From URL}[https://learn.microsoft.com/en-us/rest/api/storageservices/copy-blob-from-url]
     #
-    # Takes a key (path) and a source_key (path).
+    # Parameters:
+    # - key: destination blob path
+    # - source_key: source blob path
+    # - options: additional options
+    #   - source_client: AzureBlob::Client instance for the source container (optional)
+    #     If not provided, copies from within the same container
     #
     def copy_blob(key, source_key, options = {})
+      source_client = options.delete(:source_client) || self
       uri = generate_uri("#{container}/#{key}")
 
-      source_uri = signed_uri(source_key, permissions: "r", expiry: Time.at(Time.now.to_i + 300).utc.iso8601)
+      source_uri = source_client.signed_uri(source_key, permissions: "r", expiry: Time.at(Time.now.to_i + 300).utc.iso8601)
 
       headers = {
         "x-ms-copy-source": source_uri.to_s,

test/client/test_client.rb

@@ -12,6 +12,7 @@ def setup
     @account_name = ENV["AZURE_ACCOUNT_NAME"]
     @access_key = ENV["AZURE_ACCESS_KEY"]
     @container = ENV["AZURE_PRIVATE_CONTAINER"]
+    @public_container = ENV["AZURE_PUBLIC_CONTAINER"]
     @principal_id = ENV["AZURE_PRINCIPAL_ID"]
     @host = ENV["STORAGE_BLOB_HOST"]
     @client = AzureBlob::Client.new(
@@ -409,4 +410,26 @@ def test_get_blob_tags
 
     assert_equal({ "tag1" => "value 1", "tag 2" => "value 2" }, tags)
   end
+
+  def test_copy_between_containers
+    destination_client = AzureBlob::Client.new(
+      account_name: @account_name,
+      access_key: @access_key,
+      container: @public_container,
+      principal_id: @principal_id,
+      host: @host,
+    )
+    client.create_block_blob(key, content)
+    assert_equal content, client.get_blob(key)
+
+    destination_client.copy_blob(key, key, source_client: client)
+
+
+    assert_equal content, destination_client.get_blob(key)
+
+    begin
+      destination_client.delete_blob(key)
+    rescue AzureBlob::Http::FileNotFoundError
+    end
+  end
 end