When you develop an action for Apache OpenWhisk it can become cumbersome and time-consuming to upload the action to your OpenWhisk instance in order to test it. This is especially the case when your (Node-based) action contains NPM dependencies. You can always use Node.js to run the action locally. However, ideally one wants to run in an environment as similar to the cloud as possible - in this case run within an OpenWhisk Docker image. This is where runtest.sh comes in handy: it does exactly this - run the action locally in an OpenWhisk container. I hope this tool will make it into wsk or a similar tool for local OpenWhisk action development.
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