Function preparation

In this section, we discuss how to prepare a function using the Docker template called Docker skeleton, provided by OpenWhisk.

OpenWhisk Docker SDK

To install the Docker skeleton, normally we would do the following:

$ wsk -i sdk install docker

But if the file does not exist on your local OpenWhisk, you can download it directly from https://github.com/apache/incubator-openwhisk-runtime-docker/releases/download/sdk%400.1.0/blackbox-0.1.0.tar.gz.

The following steps are to download SDK, extract the SDK, change its directory from dockerSkeleton to docker_c, and change into the docker_c directory to check its contents:

$ curl -sSL -O https://github.com/apache/incubator-openwhisk-runtime-docker/releases/download/sdk%400.1.0/blackbox-0.1.0.tar.gz
$ tar xf blackbox-0.1.0.tar.gz
$ mv dockerSkeleton docker_c
$ cd docker_c
$ ls
buildAndPush.sh Dockerfile example.c README.md

The skeleton contains a Dockerfile, a simple C program, a bash script for building and pushing the finished function...