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Blob Storage

Process files with blob triggers and read/write blobs using bindings in PowerShell.

Blob Trigger

function.json:

{
  "bindings": [
    {
      "name": "InputBlob",
      "type": "blobTrigger",
      "direction": "in",
      "path": "uploads/{name}",
      "connection": "AzureWebJobsStorage"
    }
  ]
}

run.ps1:

param($InputBlob, $TriggerMetadata)

$name = $TriggerMetadata.name
Write-Information "Processing blob '$name' ($($InputBlob.Length) bytes)"

The blob binding delivers content as a byte[] by default. For text, convert:

$text = [System.Text.Encoding]::UTF8.GetString($InputBlob)

Output Blob Binding

Add an output binding to write a derived file:

{
  "name": "OutputBlob",
  "type": "blob",
  "direction": "out",
  "path": "processed/{name}",
  "connection": "AzureWebJobsStorage"
}

Push-OutputBinding -Name OutputBlob -Value $processedContent

Using the Az.Storage Module

For dynamic paths or listing operations, use the module with a managed identity:

Connect-AzAccount -Identity
$ctx = New-AzStorageContext -StorageAccountName $env:StorageAccountName -UseConnectedAccount
Get-AzStorageBlob -Container "uploads" -Context $ctx

Blob trigger scaling

Blob triggers on Consumption can lag under high volume. For latency-sensitive processing, prefer an Event Grid-based blob trigger or a queue.

See Also

Sources