Documentation & Usage Guides

Getting Started

Bussin runs directly in your browser. You can connect using either Entra ID or standard Connection Strings:

Option 1: Sign in with Microsoft (Entra ID)

1. Open the application at app.bussin.dev.
2. Select sign-in and authenticate using your Microsoft account. You must grant the application permissions to query your Azure resource directories and connect to your Service Bus.
3. Once logged in, Bussin automatically queries the Azure management API to display accessible subscriptions and namespaces in your sidebar. If your namespace is not listed, make sure your account has the required management permission (such as Azure Reader or Contributor) and data-plane access roles.

Option 2: Run Without Login (Connection String Mode)

1. Open the application at app.bussin.dev.
2. Select "Run without login — Connection String Mode".
3. In the sidebar, click the "Add CS" button, enter a friendly Display Name, paste your standard Service Bus Connection String, and specify any queues or topics you want to browse.
4. Click "Save Connection" to immediately access your resources. All connection strings are saved securely in your browser's local cache.

Peek Lock & Message Settlement

When reading messages from a queue or subscription using Peek-Lock, the broker reserves them for a set duration (default is 30 seconds). While locked, other consumers cannot read the messages. Bussin lets you inspect locked messages and explicitly choose an action:

• Complete: Confirms processing was successful and deletes the message from the queue.
• Abandon: Unlocks the message immediately, returning it to active status so it can be retried.
• Dead-Letter: Moves the message to the Dead-Letter Queue (DLQ). You can specify custom DeadLetterReason and ErrorDescription strings.

Bussin tracks lock leases and displays a countdown timer. If your manual inspection takes longer than the countdown, a single click extends the lock duration directly from your browser, preventing other clients from retrieving the message concurrently.

DLQ Inspection

Messages that fail processing or expire are moved to the secondary Dead-Letter Queue (DLQ) sub-queue. Inspecting these messages is key to identifying processing errors:

1. Select the queue or subscription from your folder sidebar.
2. Switch the view from "Active" to "Dead-Letter".
3. Peek the messages inline. Each message shows the headers, payload, and the specific failure reason (like MaxDeliveryCountExceeded or TTLExpiredException) appended by the broker.

Resubmitting Messages

Once you resolve the processing errors, you can replay the failed messages back to the active queue:

• Queue Resubmission: Select one or more dead-lettered messages and click "Resubmit". Bussin clones the messages and replays them back to the active queue. You can delete the originals once resubmission is complete.
• Topic Subscription Resubmission: Because Azure Service Bus does not allow publishing directly to a subscription queue, resubmitting a message from a subscription DLQ replays it back to the parent topic. Note that the message will be evaluated against all active subscription filters, potentially duplicating the message across other subscriptions.
• Bulk Replay: Use background operations to move or resubmit large backlogs of failed messages. The tool performs the actions asynchronously and displays progress bars.

Managing Subscription Filters

Subscription filters (historically called rules) determine which messages published to a topic are received by a specific subscription. Bussin allows you to inspect and modify these filters directly:

1. Select a topic subscription in the folder sidebar.
2. Click Filters in the action sidebar to open the Manage Filters dialog.
3. Inspect: View all existing filters (such as the default $Default true filter, SQL filters, or correlation filters).
4. Add Filters: Define new SQL filters (e.g. sys.Label = 'Order') or correlation filters (e.g. key-value property matches) to filter incoming messages.
5. Delete Filters: Remove outdated or incorrect filters to stop accepting unwanted messages.

Note: Modifying filters changes the live subscription configuration on the Azure Service Bus broker. Incorrect filters can cause messages to be dropped, so use with caution.

Scheduled Messages & Cancellation

Azure Service Bus allows scheduling messages to be enqueued at a future time. Bussin makes it easy to work with scheduled messages directly from your browser:

• Inspection: Scheduled messages are clearly flagged with clock icons in the message list. You can see their scheduled enqueue times in the message details view.
• Cancellation: If you need to cancel a scheduled message before its scheduled time, you can do so directly by clicking "Cancel Scheduled" in the message details modal, or by selecting multiple scheduled messages in the list and clicking "Delete". Bussin handles the AMQP cancellation command automatically under the hood.