Omnichannel Messaging - Azure Blob Storage for Pictures

Feature Name	Omnichannel Messaging - Azure Blob Storage
Feature ID	CrestApps.OrchardCore.Omnichannel.Messaging.Azure

By default the pictures sent and received in the messaging workspace are kept in the tenant's App_Data\Sites\<tenant-name>\MessagingAttachments folder. When the host's file system is replaced on deployment (containers, App Service slot swaps, ephemeral disks), that folder goes with it and the pictures disappear from conversations. Enable this feature to keep them in Azure Blob Storage instead.

What changes

• Pictures are written to, and read from, a blob container instead of the application-data folder.
• Encryption at rest is unchanged. Each picture is encrypted with the tenant's data protection keys before it is sent to Azure, so Azure only holds ciphertext.
• If the Azure settings are missing or incomplete, an error is logged and the local store stays in effect.

Persist the data protection keys too

Pictures are encrypted with the tenant's data protection keys. If those keys are also lost on deployment (the default key ring lives in App_Data), the blobs can no longer be decrypted and the pictures stay unreadable. Store the key ring somewhere durable as well, for example with the Azure Data Protection feature.

Pictures already stored locally are not moved. Copy the encrypted files from the MessagingAttachments folder into the container (same file names, under BasePath when set) if you need to keep them.

Configuration

{
  "OrchardCore": {
    "CrestApps": {
      "Omnichannel": {
        "Messaging": {
          "AzureAttachments": {
            "ConnectionString": "<storage-connection-string>",
            "ContainerName": "messaging-attachments",
            "BasePath": "{{ ShellSettings.Name }}",
            "CreateContainer": true
          }
        }
      }
    }
  }
}

Setting	Description
ConnectionString	Azure Storage account connection string.
ContainerName	Blob container name. Supports Liquid, such as messaging-{{ ShellSettings.Name }} for a container per tenant.
BasePath	Optional folder inside the container. Supports Liquid; {{ ShellSettings.Name }} keeps tenants apart in a shared container.
CreateContainer	Creates the container when the tenant starts if it does not exist.

The same environment-variable form works, for example OrchardCore__CrestApps__Omnichannel__Messaging__AzureAttachments__ConnectionString.