Chapter 40. Azure Storage Queue Service Component
Available as of Camel version 2.19
The Azure Queue component supports storing and retrieving the messages to/from Azure Storage Queue service.
Prerequisites
You must have a valid Windows Azure Storage account. More information is available at Azure Documentation Portal.
40.1. URI Format
azure-queue://accountName/queueName[?options]
The queue will be created if it does not already exist.
You can append query options to the URI in the following format: ?options=value&option2=value&…
For example, to get a message content from the queue messageQueue in the camelazure storage account, use the following snippet:
from("azure-queue:camelazure/messageQueue").
to("file://queuedirectory");40.2. URI Options
The Azure Storage Queue Service component has no options.
The Azure Storage Queue Service endpoint is configured using URI syntax:
azure-queue:containerAndQueueUri
with the following path and query parameters:
40.2.1. Path Parameters (1 parameter)
| Name | Description | Default | Type |
|---|---|---|---|
| containerAndQueueUri | Required: Container Queue compact URI. | String |
40.2.2. Query Parameters (27 parameters)
| Name | Description | Default | Type |
|---|---|---|---|
| azureQueueClient (common) | The queue service client. | CloudQueue | |
| credentials (common) | Set the storage credentials, required in most cases. | StorageCredentials | |
| credentialsAccountKey (common) | Set the storage account key used during authentication phase. | String | |
| credentialsAccountName (common) | Set the storage account name used during authentication phase. | String | |
| bridgeErrorHandler (consumer) |
Allows for bridging the consumer to the Camel routing Error Handler. This means any exceptions that occurred (for example, while the consumer was trying to pick up incoming messages) will now be processed as a message and handled by the routing Error Handler. By default, the consumer will use the | false | boolean |
| sendEmptyMessageWhenIdle (consumer) | If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead. | false | boolean |
| exceptionHandler (consumer) |
To let the consumer use a custom | ExceptionHandler | |
| exchangePattern (consumer) | Sets the exchange pattern when the consumer creates an exchange. | ExchangePattern | |
| pollStrategy (consumer) | A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurring during the poll operation before an Exchange has been created which will be routed in Camel. | PollingConsumerPoll Strategy | |
| messageTimeToLive (producer) | Message Time To Live in seconds. | int | |
| messageVisibilityDelay (producer) | Message Visibility Delay in seconds. | int | |
| operation (producer) | Queue service operation hint to the producer. | listQueues | QueueServiceOperations |
| queuePrefix (producer) | Set a prefix which can be used for listing the queues. | String | |
| synchronous (advanced) | Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). | false | boolean |
| backoffErrorThreshold (scheduler) | The number of subsequent error polls (failed due to some error) that should happen before the backoffMultipler should kick-in. | int | |
| backoffIdleThreshold (scheduler) | The number of subsequent idle polls that should happen before the backoffMultipler should kick-in. | int | |
| backoffMultiplier (scheduler) | To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt happens again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured. | int | |
| delay (scheduler) | Milliseconds before the next poll. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour). | 500 | long |
| greedy (scheduler) | If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages. | false | boolean |
| initialDelay (scheduler) | Milliseconds before the first poll starts. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour). | 1000 | long |
| runLoggingLevel (scheduler) | The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that. | TRACE | LoggingLevel |
| scheduledExecutorService (scheduler) | Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool. | ScheduledExecutor Service | |
| scheduler (scheduler) | To use a cron scheduler from either camel-spring or camel-quartz2 component | none | ScheduledPollConsumer Scheduler |
| schedulerProperties (scheduler) | To configure additional properties when using a custom scheduler or any of the Quartz2, Spring based scheduler. | Map | |
| startScheduler (scheduler) | Whether the scheduler should be auto started. | true | boolean |
| timeUnit (scheduler) | Time unit for initialDelay and delay options. | MILLISECONDS | TimeUnit |
| useFixedDelay (scheduler) | Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details. | true | boolean |
Required Azure Storage Queue Service component options
You must provide the containerAndQueue URI and the credentials.
40.3. Usage
40.3.1. Azure Queue Service operations
| Operation | Description |
|---|---|
|
| List the queues. |
|
| Create the queue. |
|
| Delete the queue. |
|
| Add a message to the queue. |
|
| Retrieve a message from the queue. |
|
| View the message inside the queue, for example, to determine whether the message arrived at the correct queue. |
|
| Update the message in the queue. |
|
| Delete the message in the queue. |
40.3.2. Azure Queue Client configuration
If your Camel Application is running behind a firewall or if you need to have more control over the Azure Queue Client configuration, you can create your own instance:
StorageCredentials credentials = new StorageCredentialsAccountAndKey("camelazure", "thekey");
CloudQueue client = new CloudQueue("camelazure", credentials);
registry.bind("azureQueueClient", client);
and refer to it in your Camel azure-queue component configuration:
from("azure-queue:camelazure/messageQueue?azureQueueClient=#client")
.to("mock:result");40.4. Dependencies
Maven users must add the following dependency to their pom.xml.
pom.xml
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-azure</artifactId>
<version>${camel-version}</version>
</dependency>
where ${camel-version} must be replaced by the actual version of Camel (2.19.0 or higher).
40.5. See Also
- Configuring Camel
- Component
- Endpoint
- Getting Started
- Azure Component
