Powershell script to automate Azure Application Gateway and Azure API Management SSL certificate renewals with Let’s Encrypt and Azure Automation.
For detailed instructions, please visit https://intelequia.com/blog/post/1012/automating-azure-application-gateway-ssl-certificate-renewals-with-let-s-encrypt-and-azure-automation
I have added a modified version of this script to do a smilar job for API Mangamenet resources that have custome domains for which you wish to have a certificate from letsencrypt.