Azure PUT Blob authentication fails in R

Question

I would like to use R and the Azure Storage\'s Put Blob API to put files into my blob storage account but it fails to authenticate my request. Unfortunately, I couldn\'t find an

Answer 1

There is an Azure offical R package Microsoft/AzureSMR on GitHub, which can help you easier using R & Azure Blob Storage, you can refer to its tutorial to know more details.

If you just want to use some Azure services like Blob Storage, not else, I think some source codes of this project are very valuable for rebuilding your code better, such as createAzureStorageSignature method which can directly help building the signature to resolve your issue.

Answer 2

I managed to resolve this issue by putting the "\n" characters and everything in the right place. Based on Gaurav Mantri's help, I used:
https://docs.microsoft.com/en-us/rest/api/storageservices/authentication-for-the-azure-storage-services

The following changes in the 'signature_string' worked:

signature_string <- paste0("PUT", "\n",            # HTTP Verb
                           "\n",                   # Content-Encoding  
                           "\n",                   # Content-Language
                           content_length, "\n",   # Content-Length
                           "\n",                   # Content-MD5
                           "text/plain", "\n",     # Content-Type
                           "\n",                   # Date
                           "\n",                   # If-Modified-Since
                           "\n",                   # If-Match  
                           "\n",                   # If-None-Match
                           "\n",                   # If-Unmodified-Since
                           "\n",                   # Range
                           # Here comes the Canonicalized Headers
                           "x-ms-blob-type:BlockBlob","\n",
                           "x-ms-date:",requestdate,"\n",
                           "x-ms-version:2015-02-21","\n",
                           # Here comes the Canonicalized Resource
                           "/",account, "/",container,"/", filename)