CkPython

Upload File in Blocks (with Content-MD5 header) and Commit the Block List

See more Azure Cloud Storage Examples

Demonstrates how to upload a file in blocks and then commit the block list. This example includes a Content-MD5 header for each block. CkPython

import sys
import chilkat

success = False

# Azure Blob Service Example: Upload a file in blocks, and then commit the block list.
# See also: https://msdn.microsoft.com/en-us/library/azure/dd135726.aspx

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

rest = chilkat.CkRest()

# Connect to the Azure Storage Blob Service
bTls = True
port = 443
bAutoReconnect = True
# In this example, the storage account name is "chilkat".
success = rest.Connect("chilkat.blob.core.windows.net",port,bTls,bAutoReconnect)
if (success != True):
    print(rest.lastErrorText())
    sys.exit()

# Provide Azure Cloud credentials for the REST call.
azAuth = chilkat.CkAuthAzureStorage()
azAuth.put_AccessKey("AZURE_ACCESS_KEY")
# The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.put_Account("chilkat")
azAuth.put_Scheme("SharedKey")
azAuth.put_Service("Blob")
# This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.put_XMsVersion("2021-08-06")
success = rest.SetAuthAzureStorage(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.

# As the blocks are uploaded, we'll keep an XML block list for the subsequent commit..
xml = chilkat.CkXml()
xml.put_Tag("BlockList")

# Any type of file can be uploaded in this way.  It can a text file, binary file, anything...
# This example will upload an XML file that is approximately 275K in size.  It can be downloaded
# at http://www.chilkatsoft.com/hamlet.xml
fac = chilkat.CkFileAccess()
success = fac.OpenForRead("qa_data/xml/hamlet.xml")
# Assuming success for the example..

# We'll upload in 16K blocks (normally a program would upload in larger block sizes than this,
# but this is just an example...)
blockSize = 16384

# How many 16K blocks?  (Including 1 for the last partial block)
numBlocks = fac.GetNumBlocks(blockSize)

crypt = chilkat.CkCrypt2()
crypt.put_HashAlgorithm("md5")

sbResponseBody = chilkat.CkStringBuilder()
uriPath = chilkat.CkStringBuilder()

dataBlock = chilkat.CkBinData()

i = 0
while i < numBlocks :

    dataBlock.Clear()
    success = fac.ReadBlockBd(i,blockSize,dataBlock)
    if (success == False):
        print(fac.lastErrorText())
        sys.exit()

    # Generate a base64 block ID.  
    # (Chilkat provides a helper method named GenBlockId to make this easy)
    # A pre-base64 encoded block ID length of 4 is sufficient in this case because
    # this file certainly won't have more than 99,999 blocks..
    blockId = fac.genBlockId(i,4,"base64")

    # Add this blockId to the list of blocks to be committed.
    xml.NewChild2("Latest",blockId)

    # Build the URI path
    uriPath.Clear()
    success = uriPath.Append("/mycontainer/hamlet.xml?comp=block&blockId=")
    success = uriPath.Append(blockId)

    contentMd5 = crypt.hashBdENC(dataBlock)
    rest.AddHeader("Content-MD5",contentMd5)

    # Upload this block..
    sbResponseBody.Clear()
    success = rest.FullRequestBd("PUT",uriPath.getAsString(),dataBlock,sbResponseBody)
    if (success == False):
        print(rest.lastErrorText())
        sys.exit()

    # Verify that we received a 201 status code.
    if (rest.get_ResponseStatusCode() != 201):
        # Examine the request/response to see what happened.
        print("response status code = " + str(rest.get_ResponseStatusCode()))
        print("response status text = " + rest.responseStatusText())
        print("response header: " + rest.responseHeader())
        print("response body (if any): " + sbResponseBody.getAsString())
        print("---")
        print("LastRequestStartLine: " + rest.lastRequestStartLine())
        print("LastRequestHeader: " + rest.lastRequestHeader())
        sys.exit()

    i = i + 1

fac.FileClose()

# Now commit the blocks.
# Let's have a look at the XML that will commit the blocks:
xmlStr = xml.getXml()
print(xmlStr)

# The XML will look like this:

# <?xml version="1.0" encoding="utf-8" ?>
# <BlockList>
#     <Latest>MDAwMA==</Latest>
#     <Latest>MDAwMQ==</Latest>
#     <Latest>MDAwMg==</Latest>
#     <Latest>MDAwMw==</Latest>
#     <Latest>MDAwNA==</Latest>
#     <Latest>MDAwNQ==</Latest>
#     <Latest>MDAwNg==</Latest>
#     <Latest>MDAwNw==</Latest>
#     <Latest>MDAwOA==</Latest>
#     <Latest>MDAwOQ==</Latest>
#     <Latest>MDAxMA==</Latest>
#     <Latest>MDAxMQ==</Latest>
#     <Latest>MDAxMg==</Latest>
#     <Latest>MDAxMw==</Latest>
#     <Latest>MDAxNA==</Latest>
#     <Latest>MDAxNQ==</Latest>
#     <Latest>MDAxNg==</Latest>
#     <Latest>MDAxNw==</Latest>
# </BlockList>

# --------------------------------------------------------------------------
# IMPORTANT: Remove the Content-MD5 header previously set in the loop above.
# --------------------------------------------------------------------------
rest.RemoveHeader("Content-MD5")

# Send the PUT Block List...
responseStr = rest.fullRequestString("PUT","/mycontainer/hamlet.xml?comp=blocklist",xmlStr)
if (rest.get_LastMethodSuccess() != True):
    print(rest.lastErrorText())
    sys.exit()

# When successful, the Azure Storage service will respond with a 201 response status code,
# with no response body.

if (rest.get_ResponseStatusCode() != 201):
    # Examine the request/response to see what happened.
    print("response status code = " + str(rest.get_ResponseStatusCode()))
    print("response status text = " + rest.responseStatusText())
    print("response header: " + rest.responseHeader())
    print("response body (if any): " + responseStr)
    print("---")
    print("LastRequestStartLine: " + rest.lastRequestStartLine())
    print("LastRequestHeader: " + rest.lastRequestHeader())
    sys.exit()

print("Success.")