Lua

Azure Storage: Download Blob to File

See more Azure Cloud Storage Examples

Sample code to download an Azure blob to a file. Lua

local chilkat = require("chilkat")

-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.

local rest = chilkat.Rest.new()

-- Connect to the Azure Storage Blob Service
local bTls = true
local port = 443
local bAutoReconnect = true
-- In this example, the storage account name is "chilkat".
local success = rest:connect("chilkat.blob.core.windows.net", port, bTls, bAutoReconnect)
if not success then
    print(rest.last_error_text)
    return
end

-- Provide Azure Cloud credentials for the REST call.
local azAuth = chilkat.AuthAzureStorage.new()
azAuth.access_key = "AZURE_ACCESS_KEY"
-- The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.account = "chilkat"
azAuth.scheme = "SharedKey"
azAuth.service = "Blob"
-- This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.xms_version = "2021-08-06"
success = rest:set_auth_azure_storage(azAuth)

-- Note: The application does not need to explicitly set the following
-- headers: Content-Length, x-ms-date, Authorization.  These headers
-- are automatically set by Chilkat.

-- Setup a file stream for the download
local fileStream = chilkat.Stream.new()
fileStream.sink_file = "C:/temp/qa_output/starfish.jpg"

-- Indicate that the call to FullRequestNoBody should send the response body
-- to fileStream if the response status code is 200.
-- If a non-success response status code is received, then nothing
-- is streamed to the output file and the error response is returned by FullRequestNoBody.
local expectedStatus = 200
rest:set_response_body_stream(expectedStatus, true, fileStream)

-- The Azure blob container is "test", the file is "starfish.jpg"
local responseStr = rest:full_request_no_body("GET", "/test/starfish.jpg")
if not rest.last_method_success then
    -- Examine the request/response to see what happened.
    print("response status code = " .. rest.response_status_code)
    print("response status text = " .. rest.response_status_text)
    print("response header: " .. rest.response_header)
    print("response body (if any): " .. responseStr)
    print("---")
    print("LastRequestStartLine: " .. rest.last_request_start_line)
    print("LastRequestHeader: " .. rest.last_request_header)
    return
end

print("Success.")