Agree that we need to revisit this behavior given at least az CLI allows you to add parameters in the deployment command that are not present in the parameters file.

@stephaniezyen -- can we discuss this in the next bicep params sync?

+1 on this... I wanted to migrate from json parameter file but this is currently blocking me as I cannot omit secret parameters I want to seed in key vaults. With json parameter file, I could not specify those and set them from CLI instead.

Closing as dup of #12019

@alex-frankel I quickly looked at the proposed scenario in #12019, but I do not see the use case specified in this issue explicitly listed in the scenario detailed in the linked issue. I probably missed it though...

With the PR that @polatengin is implementing, you will be able to declare using null which will effectively turn off validation and then you will be able to use the parameters from that .bicepparam file supplemented with whatever values are missing that you pass on the command line. Does that sound like it will cover it @ggirard07? FWIW, I think we will demo this new feature in the next community call and you will have an opportunity to ask questions about the implementation.

@alex-frankel I doubt, especially according to statement "using null is valid only on shared bicepparam files and it turns off the parameter validation process on the file".
In our case, we do not have shared parameters, so we will not have such shared bicepparam file(s) where the usage of using null will be allowed (and according to comment, it is considered only for the shared file itself anyway).
We have instead a single parameter file containing most of the parameter values. But then we specify missing parameters from command line because those are values we do not want to store in git repo, neither we can retrieve those from Azure resource using bicep itself. Most of the time, they are secret variable groups stored in ADO.

@ggirard07 - you were right :) We are going to get the first iteration out which will only allow using null in a shared file that must be consumed by the .bicepparam file used for the deployment.

@polatengin & @stephaniezyen are working on the ability to explicitly declare params which you know will be provided on the command line. Something like:

using 'main.bicep'

@providedWithDeployment()
param foo

Leaving this closed as Engin will decide if the details will be provided in #12019 or somewhere else.

I'm going to reopen this one as it came up again and we don't have the design closed yet. I don't want to lose track of this.

@alex-frankel thanks for the effort on the topic. I kindly wanted to ask if there is any progress/roadmap on this topic?

This got discussed yesterday actually. @stephaniezyen and @polatengin are working on a proposal to satisfy the requirements on this one. It's looking like there will be a few options that we will need some feedback on.

I would also expect to be possible to mix .bicepparam file along with the json file with additional parameters. An example scenario would be .bicepparam file with parameters kept in the source control and the json file with secrets.