Add slot support for function apps

[ankitkumarr]

@panchagnula, would love a review from you.

Fixes #6581, #9126

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[panchagnula]

Overall LGTM. One thing to do is in the az webapp create can you update it to check if kind is function app & throw a error message to use the new function app commands?

[ankitkumarr]

@panchagnula, I have updated the PR to add an error message when use webapp's create command. Please have another look if you don't mind :)

[bigdatamoore]

Hi @ankitkumarr thanks for implementing this. I was able to check out the repo and test this out and was able to create a slot. I was wondering about the ability to deploy using az functionapp to slots. I believe az webapp has a deployment option (az webapp deployment source config-zip) that has a --slot option. Are you planning on adding the same for the az functionapp deployment commands?

https://docs.microsoft.com/en-us/cli/azure/webapp/deployment/source?view=azure-cli-latest#az-webapp-deployment-source-config-zip

[ankitkumarr]

@bigdatamoore, this PR should have addressed that as well. webapp and functionapp use a lot of the same functionality underneath. I turned slots on for all the functionapp commands that should have it. Let me know if you are unable to use it. Thanks!

[bigdatamoore]

@ankitkumarr I was able to deploy a c# function using the az functionapp deployment source config-zip --slot command. I tried it with a python function and got the following error:

(venv) PS > az functionapp deployment source config-zip --resource-group myresourcegroup --name myfunction1 --src test-function.zip --slot staging
Getting scm site credentials for zip deployment
Starting zip deployment. This operation can take a while to complete ...
The command failed with an unexpected error. Here is the traceback:

Expecting value: line 1 column 1 (char 0)
Traceback (most recent call last):
  File "C:\Users\240721\source\repos\azure-cli\venv\lib\site-packages\knack\cli.py", line 206, in invoke
    cmd_result = self.invocation.execute(args)
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\commands\__init__.py", line 561, in execute
    raise ex
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\commands\__init__.py", line 619, in _run_jobs_serially
    results.append(self._run_job(expanded_arg, cmd_copy))
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\commands\__init__.py", line 612, in _run_job
    six.reraise(*sys.exc_info())
  File "C:\Users\240721\source\repos\azure-cli\venv\lib\site-packages\six.py", line 693, in reraise
    raise value
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\commands\__init__.py", line 589, in _run_job
    result = cmd_copy(params)
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\commands\__init__.py", line 298, in __call__
    return self.handler(*args, **kwargs)
  File "c:\users\240721\source\repos\azure-cli\src\azure-cli-core\azure\cli\core\__init__.py", line 467, in default_command_handler
    return op(**command_args)
  File "c:\users\240721\source\repos\azure-cli\src\command_modules\azure-cli-appservice\azure\cli\command_modules\appservice\custom.py", line 296, in enable_zip_deploy
    authorization, timeout)
  File "c:\users\240721\source\repos\azure-cli\src\command_modules\azure-cli-appservice\azure\cli\command_modules\appservice\custom.py", line 2233, in _check_zip_deployment_status
    res_dict = response.json()
  File "C:\Users\240721\source\repos\azure-cli\venv\lib\site-packages\requests\models.py", line 897, in json
    return complexjson.loads(self.text, **kwargs)
  File "C:\Python36\lib\json\__init__.py", line 354, in loads
    return _default_decoder.decode(s)
  File "C:\Python36\lib\json\decoder.py", line 339, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "C:\Python36\lib\json\decoder.py", line 357, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

[ankitkumarr]

@bigdatamoore, oh are you on a Linux Consumption plan? Slots aren't yet supported for Linux Consumption, neither is the az functionapp deployment source config-zip command yet. I believe we are tracking support of these scenarios.

[bigdatamoore]

Ok thanks. That is what I figured. Thanks for the update. I will wait until those are supported. Any idea as to when that could be?

[bigdatamoore]

@ankitkumarr
Ok nevermind. I was able to get it working. Sorry for the false alarm. The problem I had was that in my staging slot I had the WEBSITE_CONTENTSHARE set to the same value as my production slot. So when I updated one, it was automatically updating the other as well.

I have confirmed that the CLI is working with slots for C# functions. I was able to create a slot, deploy to the slot, and then use the CLI to swap the slots.

[ankitkumarr]

@bigdatamoore, thanks for reporting this. I will take a look at your issue later today.

As for the actual code, you did find the correct function enable_zip_deploy. But, it is linked directly to the command here -

azure-cli/src/command_modules/azure-cli-appservice/azure/cli/command_modules/appservice/commands.py

Line 253 in cbb0c77

g.custom_command('config-zip', 'enable_zip_deploy')

. That's why you don't see any code references to it.
The reference you linked is actually for a different command az webapp up that uses the function to deploy.

Anyway, I will try and get a repro to see what's going on.

[ankitkumarr]

@bigdatamoore, whoops, I missed you comment. Thanks for verifying. Glad you were able to resolve.

[bigdatamoore]

@ankitkumarr, can you test out the create slot command and see if it updates the WEBSITE_CONTENTSHARE setting value? When doing this via the portal, the WEBSITE_CONTENTSHARE is automatically appended with a random string. However when doing this via the CLI it is copying the same value that is in the production slot. So that was actually causing the behavior that I was seeing. Probably you will want to add some random string to the end of the existing value so that you don't have these collisions when using the CLI to create slots. This may be by design but I am not sure. Thanks.