Two Quick OpenWhisk/IBM Cloud Functions Updates

It’s going to be a slow holiday week for me but I thought I’d share two interesting updates to OpenWhisk/IBM Cloud Functions that will be useful to developers. As a reminder, the wsk CLI does not prompt you to update when it is out of date. Read my guide for help on how to check and update your CLI. Ok, so what changed?

CRON Details for Triggers

The first change isn’t huge, but is real useful for me. Previously when you fetched details for CRON-based triggers, you did not get details about the CRON schedule back. So if you forgot, or weren’t sure of, the schedule for your trigger, you were kind of out of luck. Now these details are returned. Here is a simple example of what you will see when running wsk trigger get X (I removed the rest of the content):

"config": {
"cron": "0 */3 * * *",
"name": "randomcomicbook_trigger",
"namespace": " Space",
"payload": {"payload": ""}

You can paste this into to “translate” this into English: “At minute 0 past every 3rd hour.”

IBM Cloud Service Binding

The next update only applies to the bx CLI. I don’t blog about the bx CLI much when discussing OpenWhisk as I don’t want to assume all my readers are using OpenWhisk on IBM Cloud (which, by the way, is the new name for Bluemix). The bx CLI is used to interact with IBM Cloud and is pretty powerful. To work with OpenWhisk on IBM Cloud, you simply add the plugin and then you can do bx wsk as a - for the most part - mirror of the generic wsk CLI. However, there are some differences for things that are specific to IBM Cloud.

One such difference is pretty bad ass if you are using any services. So for example, Tone Analyzer. Whenever you create an IBM Cloud service, you get a set of credentials. You can easily use them in OpenWhisk actions by setting them up as parameters. You can make this even easier by setting them as default parameters so you don’t have to pass them.

But now you can use “service bindings” instead. Basically set it up such that the credentials are passed to the action. So for example, given a service named ‘conversation’ and an action named ‘enterpriseCatDemo’, you could do this to have the credentials passed: bx wsk service bind conversation enterpriseCatDemo. The values will be passed as arguments named __bx_creds which is an object. It will contain the key conversation which includes the credentials. So if you bound another service named foo, then it would be in that key instead.

I’d show a proper demo, but there’s already a full blog post up on this demonstrating everything: Simplify binding your IBM Cloud services to serverless Functions.

I’m adding a quick note here after publication - thank you to Carlos Santana for reminding me. Much like how wsk needs to be updated, so does the wsk plugin for bx. You can do that via the command: bx plugin update.

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About Raymond Camden

Raymond is a developer advocate for Extend by Auth0. He focuses on serverless and enterprise cat demos. If you like this article, please consider visiting my Amazon Wishlist or donating via PayPal to show your support.

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