Database Reference
In-Depth Information
},
"body":"the body goes here."
}]
Note that the values for each of the header elements must be a string, even if
the real value is a number. The Flume event object only supports strings in
the header metadata.
The
BlobHandler
is much simpler, being designed to take in relatively
large binary objects. No attempt is made by the handler to interpret the
events.
WARNING
Events are buffered in memory, so very large elements could fill the
Java heap allocated to the Flume process. This causes Flume to crash
and, depending on the channel, could cause a loss of data. Therefore, it
is important to restrict the size of objects sent to a BlobHandler.
Java Message Service (JMS) Source
The Java Message Service (JMS) source allows Flume to integrate with
Java-based queuing systems. These systems are popular mechanisms for
moving data around when the entire stack is Java-based. The JMS source
has primarily been tested with ActiveMQ, but it should be able to attach to
any JMS provider.
Connecting to a JMS provider requires some familiarity with JMS. It
minimally requires providing an initial context factory name, a connection
factory, and a provider URL. It also requires a destination name and a
destination type that may be either a queue or a topic. For example, to
connect to a local ActiveMQ server with a queue named
DATA
, you could use
the following configuration:
agent_1.source.source-1.type=jms
agent_1.source.source-1.initialContextFactory=
org.apache.activemq.jndi.ActiveMQInitialContextFactory
agent_1.source.source-1.connectionFactory=
