Hello world

To start off with we are going to look at deploying two very simple hello world functions. The first simply prints Hello World! and the second takes an input and then displays it back to you.

The basic example

First of all, we need our function. The static hello-world function requires the following three lines of Python code:

import json
def handler():
    return "Hello World!"

Place the preceding code, which is also available in the Chapter04/hello-world folder of the GitHub repository that accompanies this book, in a file called hello.py.

Now we have our function we can deploy it into the default namespace by running the following command:

$ kubeless function deploy hello \
  --from-file hello.py
  --handler hello.handler \
  --runtime python2.7 \
--trigger-http

This command creates a function called hello, using the file hello.py. Whenever the function called hello.handler is executed, we are using the python2.7 runtime, and our function is set to be triggered by an http request...