!!!Renew Azure SAS token via Azure User impersonation
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This example demonstrates using the Azure Delegation settings to renew an Azure SAS token configured on a user at [User Manager]. For more info see: Authorize access to blobs using Microsoft Entra ID Link: [https://learn.microsoft.com/en-us/azure/storage/blobs/authorize-access-azure-active-directory]\\
The job is eligible for daily scheduling.\\ 
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[attachments|renew_azure_sas_token_user_impersonation_full.png]\\
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User's Azure Blob VFS with user delegation settings (for more info see: [Azure Integration]):\\ 
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[attachments|azure_blob_user_delegation_settings.png]\\
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!!Section 1.\\
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It loads the user's VFS file, parses it, and retrieves the previous SAS token expiry date.\\
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[attachments|find_azure_vfs_file.png]\\
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__!!!Configure __your user's VFS path at the Find task.\\
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[attachments|file_parse_azure_vfs_file.png]\\
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Parse the VFS XML file to retrieve the Azure SAS token expiration.\\
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{{{
vfs_xml          = {xml_parse_start}{file_contents}{xml_parse_end}
org_sas_token    = {decrypt_start}{v_0_sas_token}{decrypt_end}
se_all           = {split_start:&se=:1}{org_sas_token}{split_end}
se_end_index     = {indexof_start:&:0}{se_all}{indexof_end}
se               = {substring_start:0:{se_end_index}}{se_all}{substring_end}
sas_token_expire = {parse_start:yyyy-MM-dd'T'HH~..~mm~..~ss'Z'}{se}{parse_end}
difference       = {math_start:l}{sas_token_expire}-{now}{math_end}
}}}\\
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[attachments|get_azure_sas_token_info.png]\\
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!!Section 2.\\
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Verify the expiration of the SAS token and store the refresh token. The refresh token must be saved each time and stored as a persistent variable.\\
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[attachments|jump_difference_greater_then_zero.png]\\
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Set the difference to zero if it is less than zero.\\
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[attachments|set_difference_as_zreo.png]\\
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Verify if the difference is less than two days.\\
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[attachments|check_if_difference_is_less_then_two_day.png]\\
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Determine whether the persistent variable is present. On the first run, it will not exist.\\
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[attachments|check_persist_variable.png]\\
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Check for the presence of the persistent variable.\\
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[attachments|check_azure_refresh_token.png]\\
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Persist the Azure's refresh token.\\
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{{{
persist_azure_refresh_token = {decrypt_start}{v_0_azure_user_delegation_refresh_token}{decrypt_end}
}}}\\
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[attachments|save_azure_refresh_token.png]\\
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!!Section 3.\\
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This section retrieves the Access Token using the Azure Refresh Token to obtain the user delegation key.\\
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Construct the request body of the HTTP call.\\
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{{{
client_id       = {decrypt_start}{v_0_azure_user_delegation_client_id}{decrypt_end}
tenant_id       = {decrypt_start}{v_0_azure_user_delegation_client_tenant}{decrypt_end}
client_secret   = {decrypt_start}{v_0_azure_user_delegation_client_secret}{decrypt_end}

renew_refresh_token_post_data = client_id={client_id}&client_secret={client_secret}&refresh_token={persist_azure_refresh_token}&grant_type=refresh_token

blob_storage_account_name = {url_start:user}{decrypt_start}{v_0_url}{decrypt_end}{url_end}
}}}\\
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[attachments|azure_oauth_2_data.png]\\
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Retrieve the Access Token through the HTTP Task.\\
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{{{
URL          = https://login.microsoftonline.com/{tenant_id}/oauth2/v2.0/token
POST Data    = {renew_refresh_token_post_data}
Content-Type = application/x-www-form-urlencoded
}}}
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[attachments|CrushTaskExample18/oauth2_http_task.png]\\
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Verify the HTTP response.\\
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[attachments|check_aouth2_http_response.png]\\
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Parse the HTTP response and build the request body for the HTTP call to get the delegation key. __!!! We must store the new refresh token to maintain offline access.\\
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{{{
response                    = {json_parse_start}{http_response_log}{json_parse_end}
persist_azure_refresh_token = {refresh_token}
after_6_days_in_millis      = {math_start:l}{now}+518400000{math_end}
sas_start                   = {rparse_start:yyyy-MM-dd'T'HH~..~mm~..~ss'Z'}{yesterday}{rparse_end}
sas_end                     = {rparse_start:yyyy-MM-dd'T'HH~..~mm~..~ss'Z'}{after_6_days_in_millis}{rparse_end}
delegation_key_post_body    = <?xml version="1.0" encoding="utf-8"?>{n}<KeyInfo>{n}    <Start>{sas_start}</Start>{n}    <Expiry>{sas_end}</Expiry>{n}</KeyInfo>
        
}}}\\
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[attachments|variables_for_delegation_key_call.png]\\
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!!Section 4.\\
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This section retrieves the user delegation key, constructs a new Azure SAS token, and replaces the old value with the new value in the user's VFS file.\\
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HTTP call to obtain the user delegation key:\\
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{{{
URL       = https://{blob_storage_account_name}.blob.core.windows.net/?restype=service&comp=userdelegationkey
Post Data = {delegation_key_post_body}

Headers:

x-ms-version  =  2022-11-02
Authorization =  Bearer {access_token}
}}}\\
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[attachments|user_delgation_http_call.png]\\
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[attachments|check_response_code_user_delegation.png]\\
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Parse the response of the Azure User Delegation HTTP call. The response XML lacks the 'properties' type, so we include it for proper XML file parsing.\\
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{{{
parse_response     = {xml_parse_start}{replace_start:<UserDelegationKey:<UserDelegationKey type="properties"}{http_response_log}{replace_end}{xml_parse_end}
permission         = rwdl
user_delgation_key = {Value}
}}}\\
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[attachments|user_delegation_parse_result.png]\\
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Construct the Azure SAS token.\\
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{{{
azure_sas_string_to_sign = {permission}{n}{n}{sas_end}{n}/blob/crushftpdatalake2/folderkz{n}{SignedOid}{n}{SignedTid}{n}{SignedStart}{n}{SignedExpiry}{n}b{n}{SignedVersion}{n}{n}{n}{n}{n}https{n}{SignedVersion}{n}c{n}{n}{n}{n}{n}{n}{n}
signature                = {sign_hmacsha256_start:{user_delgation_key}}{azure_sas_string_to_sign}{sign_hmacsha256_end}
azure_sas_token          = sp={permission}&se={sas_end}&skoid={SignedOid}&sktid={SignedTid}&skt={SignedStart}&ske={SignedExpiry}&sks=b&skv={SignedVersion}&spr=https&sv={SignedVersion}&sr=c&sig={sign_hmacsha256_value} 
azure_sas_token_encoded  = {encrypt_start}{azure_sas_token}{encrypt_end}
}}}\\
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[attachments|construct_azure_sas_token.png]\\
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Swap the old Azure Sas token with the newly created one.\\
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{{{
Find Text    = <sas_token>{v_0_sas_token}</sas_token>
Replace With = <sas_token>{azure_sas_token_encoded}</sas_token>
}}}\\
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[attachments|replace_azure_sas_token.png]\\
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!!Section 5.\\
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This section covers the error handling using the Default Failure Task (see at [Handling Job Failures]). 
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[attachments|default_failure_task.png]\\
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