While working on Group provisioning process (blog here), we encountered an issue with parallel calls to Azure Functions from Flow. Even though, Microsoft flow supports sequencing flow runs but doesn’t queue them one after the other. Bummer !! However, we were able queued the requests at Azure Http function level, which was quite simple actually.
Azure Queue Triggers are mostly recommended in this case but with Queue trigger, the queue would always trigger at least two runs and the poison queue wouldn’t trigger after failing for more than 5 times
Hence we ended up managing it by the Http trigger function.
The process is quite simple and could be easily done by modifying the host.json file of the Azure function.
Note: Host.json is a global configuration file for all functions within a Function app, hence the below changes would affect all functions in that particular app.
Note: More details about host.json schema could be found in the Microsoft article here.