An Azure timer function for keeping sites alive.
First, prior to deployment of any functions within your function app, you'll need to upgrade the Runtime version under the Function app settings to beta.
Second, under the function app's Application settings, you'll need to update the WEBSITE_NODE_DEFAULT_VERSION to 8.9.4. This will upgrade the installed version of NodeJS within your app instance.
Finally, update Azure function's core tooling. Go to Kudu by visiting: http://yourwebapp.scm.azurewebsites.net. At the top menu, choose Debug Console -> CMD. At the command line, type the following:
npm i -g azure-functions-core-tools@core
You are now ready to deploy the function.
Create an Azure function and upload this code to it.
Once all of the code in this repo has been uploaded, go back to Kudu by visiting:
http://yourwebapp.scm.azurewebsites.net. At the top menu, choose Debug Console -> CMD. Using the folders or the command-line navigate to the folder: site/wwwroot/functionName. From the prompt, enter the following:
npm i
This will take a couple of seconds, but will install the few node dependencies of the app.
That's it. Now, your function should execute every 5 minutes (default, but can be changed in the functions.json) and ping each site in the sites.json file.
Every time you modify the sites.json file, you'll need to restart the function in order to pick up the changes.