How to authenticate an azure storage api request using a storage account key in python?

Question

I am trying to authenticate a get request to the azure storage api using the below python function however I am getting the following error:

<Response [403]>
Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature.

The url of the request I am trying to make is:

'https://{account name}.dfs.core.windows.net/{file system}?directory={directory}&recursive=False&resource=filesystem'

Documentation for the REST api: https://docs.microsoft.com/en-us/rest/api/storageservices/datalakestoragegen2/path/list

Documentation on how to authenticate using account key: https://docs.microsoft.com/en-us/rest/api/storageservices/authorize-with-shared-key

def get_shared_access_authorization(self, directory):
        directory = directory
        file_system_name = self.fileSystem
        storage_account_name = self.storageAccountName
        storage_account_key = self.accountKey
        request_time = datetime.datetime.utcnow().strftime('%a, %d %b %Y %H:%M:%S GMT')

        string_params = {
            'verb': 'GET',
            'Content-Encoding': '',
            'Content-Language': '',
            'Content-Length': '',
            'Content-MD5': '',
            'Content-Type': '',
            'Date': '',
            'If-Modified-Since': '',
            'If-Match': '',
            'If-None-Match': '',
            'If-Unmodified-Since': '',
            'Range': '',
            'CanonicalizedHeaders': 'x-ms-date:' + request_time + '\nx-ms-version:' + '2018-11-09' + '\n',
            'CanonicalizedResource': '/' + storage_account_name + '/' + file_system_name  + '\ndirectory:'+directory+'\nrecursive:false\nresource:filesystem'
        }

        string_to_sign = (string_params['verb'] + '\n'
                          + string_params['Content-Encoding'] + '\n'
                          + string_params['Content-Language'] + '\n'
                          + string_params['Content-Length'] + '\n'
                          + string_params['Content-MD5'] + '\n'
                          + string_params['Content-Type'] + '\n'
                          + string_params['Date'] + '\n'
                          + string_params['If-Modified-Since'] + '\n'
                          + string_params['If-Match'] + '\n'
                          + string_params['If-None-Match'] + '\n'
                          + string_params['If-Unmodified-Since'] + '\n'
                          + string_params['Range'] + '\n'
                          + string_params['CanonicalizedHeaders']
                          + string_params['CanonicalizedResource'])

        signed_string = base64.b64encode(
            hmac.new(base64.b64decode(storage_account_key), msg=string_to_sign.encode('utf-8'),
                     digestmod=hashlib.sha256).digest()).decode()

        headers = {
            'x-ms-date': request_time,
            'x-ms-version': '2018-11-09',
            'Authorization': ('SharedKeyLite ' + storage_account_name + ':' + signed_string)
        }

        return headers

I have checked that all inputs (directory, file system name, storage account name and account key) are correct. Any help would be greatly appreciated.

Update: I have tried using both 'SharedKey' and 'SharedKeyLite' in the auth header.

Update 2: The problem was solved by swapping from 'false' to 'False'. I have generalised the working function and included it below.

def get_shared_access_authorization(self, directory, file_system_name, storage_account_name, storage_account_key):

        request_time = datetime.datetime.utcnow().strftime('%a, %d %b %Y %H:%M:%S GMT')

        string_params = {
            'verb': 'GET',
            'Content-Encoding': '',
            'Content-Language': '',
            'Content-Length': '',
            'Content-MD5': '',
            'Content-Type': '',
            'Date': '',
            'If-Modified-Since': '',
            'If-Match': '',
            'If-None-Match': '',
            'If-Unmodified-Since': '',
            'Range': '',
            'CanonicalizedHeaders': 'x-ms-date:' + request_time + '\nx-ms-version:' + '2018-11-09' + '\n',
            'CanonicalizedResource': '/' + storage_account_name + '/' + file_system_name  + '\ndirectory:'+directory+'\nrecursive:False\nresource:filesystem'
        }

        string_to_sign = (string_params['verb'] + '\n'
                          + string_params['Content-Encoding'] + '\n'
                          + string_params['Content-Language'] + '\n'
                          + string_params['Content-Length'] + '\n'
                          + string_params['Content-MD5'] + '\n'
                          + string_params['Content-Type'] + '\n'
                          + string_params['Date'] + '\n'
                          + string_params['If-Modified-Since'] + '\n'
                          + string_params['If-Match'] + '\n'
                          + string_params['If-None-Match'] + '\n'
                          + string_params['If-Unmodified-Since'] + '\n'
                          + string_params['Range'] + '\n'
                          + string_params['CanonicalizedHeaders']
                          + string_params['CanonicalizedResource'])

        signed_string = base64.b64encode(
            hmac.new(base64.b64decode(storage_account_key), msg=string_to_sign.encode('utf-8'),
                     digestmod=hashlib.sha256).digest()).decode()

        headers = {
            'x-ms-date': request_time,
            'x-ms-version': '2018-11-09',
            'Authorization': ('SharedKey ' + storage_account_name + ':' + signed_string)
        }

        return headers

Answer 1

Please try by changing SharedKeyLite to SharedKey authorization. Essentially change the following line of code:

'Authorization': ('SharedKeyLite ' + storage_account_name + ':' + signed_string)

to

'Authorization': ('SharedKey ' + storage_account_name + ':' + signed_string)