Kafka For Pythonistas

Matt Howlett has an introduction to Apache Kafka, designed for Python developers:

In the call to the produce method, both the key and value parameters need to be either a byte-like object (in Python 2.x this includes strings), a Unicode object, or None. In Python 3.x, strings are Unicode and will be converted to a sequence of bytes using the UTF-8 encoding. In Python 2.x, objects of type unicode will be encoded using the default encoding. Often, you will want to serialize objects of a particular type before writing them to Kafka. A common pattern for doing this is to subclass Producer and override the produce method with one that performs the required serialization.

The produce method returns immediately without waiting for confirmation that the message has been successfully produced to Kafka (or otherwise). The flush method blocks until all outstanding produce commands have completed, or the optional timeout (specified as a number of seconds) has been exceeded. You can test to see whether all produce commands have completed by checking the value returned by the flush method: if it is greater than zero, there are still produce commands that have yet to complete. Note that you should typically call flush only at application teardown, not during normal flow of execution, as it will prevent requests from being streamlined in a performant manner.

This is a fairly gentle introduction to the topic if you’re already familiar with Python and have a familiarity with message broker systems.

Related Posts

A Simple Example With Spark And Kafka

Gary Dusbabek has a nice example showing how to build a simple application with Spark and Kafka: This is a hands-on tutorial that can be followed along by anyone with programming experience. If your programming skills are rusty, or you are technically minded but new to programming, we have done our best to make this […]

Read More

Talking To Secure Hadoop Clusters

Mubashir Kazia shows how to connect to a secured Hadoop cluster using Active Directory: The primary form of strong authentication used on a secure cluster is Kerberos. Kerberos supports credentials delegation where a server process to which a user has authenticated, can perform actions on behalf of the user. This involves the server process accessing […]

Read More

Categories

June 2017
MTWTFSS
« May Jul »
 1234
567891011
12131415161718
19202122232425
2627282930