How to retrieve the autogenerated domain url inside a function ?

Is there an environment variable that I can use to retrieve the auto generated domain of a function. ? I would like to provide it as a callback url to an api.
Thanks in advance.

If anything, it might be in the headers. Otherwise, you may need to use an environment variable.

Unfortunately there is no header with the generated domain. I know that I can create a function variable with it but I wanted to have a fully automated process via cli with no human intervention to configure my Appwrite backend instance. I'm almost there this was the last bit of configuration remaining. If someone have a suggestion to retrieve that value via cli that's fine too because then I can create a variable via cli.