Understanding Consumers

Consumers are applications that you create such as analytics applications, reporting tools, or enterprise dashboards.

They use the MapR-ES APIs to request messages from topics that they are interested in. In case of server failure, consumer clients continually retry requests automatically. A consumer client library sends unread messages, which consumers extract data from.

Consumers can run as separate processes on a single machine and as processes on different machines.

Before a consumer can read messages from topics, the user ID running the consumer needs these permissions:
  • The readAce permission on the volume where the streams are located. For information about how to set permissions on volumes, see Setting Whole Volume ACEs.
  • The consumeperm permission on the streams where the topics are located. Users with the adminperm permission on those streams can grant the consumeperm permission.