How to make Invoke-RestMethod GET and PUT requests to Azure table storage using SAS key - azure

Question

This is a two-part question. I am in the process of automating tasks that a) require information from my Azure table and b) need to update specific entities in my Azure table. I've currently been able to accomplish this by using either of the 2 provided access keys but think this is an unsafe practice and want to define individual policies for different groups and so want to transition into using generated SAS keys.
a) I can currently use SAS policies to retrieve the whole table and find the information I need but I think a better method is to perform an individual query that only pulls the single entity that matches a specific property I'm looking for (e.g. pull all properties of an entity that matches a customer ID: "000000001"). How can I change my code to accomplish this?
$tableName = "accountTD"
$sasReadToken = '<SAS token here>'
$tableUri = "https://$storageAccount.table.core.windows.net/$tableName$sasReadToken"
$GMTTime = (Get-Date).ToUniversalTime().toString('R')
$header = #{
'x-ms-date' = $GMTTime;
Accept = 'application/json;odata=nometadata'
}
$finalResult = Invoke-WebRequest -Uri $tableUri -Headers $header -UseBasicParsing
$finalResult = $finalResult.Content | ConvertFrom-Json
$finalResult.value
b) I also need to update the same entity in the table and can't seem to figure out how to authorize it with my generated SAS key. I'm not sure whether to use Invoke-WebRequest or Invoke-RestMethod or how to go about either of them. Here's what I have so far based on my research.
function addUpdateEntity ($tableName, $PartitionKey, $RowKey, $entity){
$sasReadToken = '<SAS token here>'
$resource = "$tableName(PartitionKey='$PartitionKey',RowKey='$Rowkey')"
$tableUri = "https://$storageAccount.table.core.windows.net/$tableName$sasReadToken"
$GMTTime = (Get-Date).ToUniversalTime().toString('R')
$header = #{
'x-ms-date' = $GMTTime;
Accept = 'application/json;odata=nometadata'
}
$body = $entity | ConvertTo-Json
$item = Invoke-RestMethod -Method PUT -Uri $tableUri -Headers $headers -Body $body -ContentType application/json
}
$mBody = #{
PartitionKey = "MPS02000"
RowKey = "2019-000101"
appUpdateMode = "1"
m_CustID = "000000001"
}
addUpdateEntity -TableName "atdMachines" -PartitionKey $mBody.PartitionKey -RowKey $mBody.RowKey -entity $mBody

Answer 1

Q1. Pull all properties of an entity that matches a customer ID
Answer: You can use $filter query expression. For example, I have 2 entities in my testTable:
I can get the entity whose Id equals to 00001 by making a request as following:
GET https://storagetest789.table.core.windows.net/testTable?{sastoken}&$filter=(Id eq '00001')
$storageAccount = "storagetest789"
$tableName = "testTable"
$sasReadToken = "?sv=2019-02-02&ss=t&sr***************D"
$filter = "`$filter=(Id eq '00001')"
$tableUri = "https://$storageAccount.table.core.windows.net/$tableName$sasReadToken&$filter"
$GMTTime = (Get-Date).ToUniversalTime().toString('R')
$header = #{
'x-ms-date' = $GMTTime;
Accept = 'application/json;odata=nometadata'
}
$finalResult = Invoke-WebRequest -Uri $tableUri -Headers $header -UseBasicParsing
$finalResult = $finalResult.Content | ConvertFrom-Json
$finalResult.value
Result:
Q2. Update the same entity in the table
Answer: Both Invoke-WebRequest and Invoke-RestMethod are suitable for making a HTTP request here. I find some mistakes in your scripts, here is the fixed one:
function addUpdateEntity ($tableName, $PartitionKey, $RowKey, $entity){
$storageAccount = "storagetest789"
$tableName = "testTable"
# Need write access
$sasWriteToken = "?sv=2019-02-02&ss=t&s*****************************D"
$resource = "$tableName(PartitionKey='$PartitionKey',RowKey='$Rowkey')"
# should use $resource, not $tableNmae
$tableUri = "https://$storageAccount.table.core.windows.net/$resource$sasWriteToken"
# should be headers, because you use headers in Invoke-RestMethod
$headers = #{
Accept = 'application/json;odata=nometadata'
}
$body = $entity | ConvertTo-Json
$item = Invoke-RestMethod -Method PUT -Uri $tableUri -Headers $headers -Body $body -ContentType application/json
}
$mBody = #{
PartitionKey = "p1"
RowKey = "r1"
Id = "00001"
Value = "new value"
}
addUpdateEntity -TableName "atdMachines" -PartitionKey $mBody.PartitionKey -RowKey $mBody.RowKey -entity $mBody
Result: