Access to specific physical destinations on the broker is controlled by authorization rules with a resource type of queue or topic, as the case may be. These rules regulate access to the following operations:
Sending messages to a queue: produce operation
Receiving messages from a queue: consume operation
Publishing messages to a topic: produce operation
Subscribing to and consuming messages from a topic: consume operation
Browsing a queue: browse operation
By default, all users and groups are authorized to perform all of these operations on any physical destination. You can change this by editing the default authorization rules in the access control properties file or overriding them with more specific rules of your own. For example, the rule
denies all members of the user group the ability to subscribe to the topic Admissions.
When a client creates a message producer or consumer for a physical destination that does not already exist, the broker will auto-create the destination (provided that the broker’s imq.autocreate.queue or imq.autocreate.topic property is set to true).
The final section of the access control file controls the ability of users and groups to auto-create destinations, and to access any auto-created destinations. This is governed by authorization rules with a resourceType of queue or topic and an operation element of create. the resourceVariant element is omitted, since these rules apply to all auto-created queues or all auto-created topics, rather than any specific destination.
The default access control file contains the rules
authorizing all users to have physical destinations auto-created for them by the broker, and to have access to any auto-created destinations. You can edit the file to restrict such authorization for specific users. For example, the rule
denies user Snoopy the ability to auto-create topic destinations or to access any auto-created topic destinations.
The effect of such auto-creation rules must be congruent with that of other physical destination access rules. For example, if you change the destination authorization rule to prohibit any user from sending a message to a queue, but enable the auto-creation of queue destinations, the broker will create the physical destination if it does not exist, but will not deliver a message to it.