Support running linter from CLI separately to build

[johndowns]

Is your feature request related to a problem? Please describe.
When I create a CI/CD pipeline to work with my Bicep templates, I want to run linter rules and fail the build if there are any warnings or errors. Currently, the bicep build command executes the linter but shows linter warnings as outputs, and the exit code is 0, so it's not easy to pick up that linter rules failed. Additionally, bicep build emits a JSON template, which I don't need.

Describe the solution you'd like
Please provide a new bicep lint command, which will run the same linter rules as bicep build, but will return a meaningful exit code (perhaps 0 for no linter warnings, 1 for warnings, 2 for errors?) and that doesn't emit a JSON template.

[MarcusFelling]

@johndowns - would using bicepsettings.json to set all of the rules to error level meet your needs? The error build-time behavior will throw exit code of 1 and should cause the build to fail. bicepsettings.json can sit in source control alongside your templates and the CLI will automatically pick it up.

[johndowns]

@MarcusFelling I don't think so. It's a workaround, but I don't think it's the optimal solution.

The key thing to me is that:

• At development time, warnings might be something I ignore because I'm trying to get something done.
• At release time (in my CI/CD process), I want to make sure the warnings are treated as errors and fail the build. This is the last chance to catch issues before they potentially hit production.

So to me, it'd be better if I could have a bicep lint command that fails with any linter violations (except those I've disabled). Alternatively, maybe there could be a new bicep build --treat-warnings-as-errors switch that would do the same thing.

[anthony-c-martin]

@johndowns - does this ask apply purely to linter warnings, or are you looking for any warnings to be treated as errors? For example, the following type validation message is a core compiler warning (not a linter warning):

[johndowns]

@anthony-c-martin In principle it'd be good to apply it to all warnings, but my concern is that there are still some situations where RPs haven't properly documented their schemas, and so compiler warnings will appear that I have no control over. If the any() function could be used as an escape hatch for all situations, or if there was another way of telling Bicep to ignore a specific warning for a specific line/resource, then I'd be in favour of that. But as of today, I think separating out the linter results would be a better approach.

[jonas-lomholdt]

I came here because I was looking for this exact thing. Having a bicep lint command that potentially could also output the warnings/errors as json would also be beneficial.

[zhengchang907]

Any plans of this feature, thought it would be a handy one.

[alex-frankel]

We agree it would be a useful command to add, but don't have the time to implement it ourselves. It would be great if someone could make an external contribution for this one.