How to check if the current invocation is running `publish`?

[agocke]

Title basically says it all -- but in certain cases I'd like to know in the project file whether we're doing a build or a publish. In particular, I might want a non-self-contained build by default, but always want a self-contained publish.

[agocke]

• @dsplaisted @marcpopMSFT

[dsplaisted]

There isn't a way to tell what targets MSBuild will run (before it actually runs them), so there's not a good way to do this.

On the other hand, we would like to be able to have different defaults and behavior between build and publish. The first step toward that just went in with #25991.

With that change, you could check the _IsPublishing property to see if the build was run via dotnet publish. However, the property would not be set if you ran dotnet build /t:Publish or msbuild /t:Publish.

[marcpopMSFT]

@dsplaisted are there plans (or even capability) to set ispublishing when using the /t flag? Not sure what this issue tracks with 25991 merged now.

[dsplaisted]

No concrete plans I think. We could detect and handle something like /t:Publish in the CLI, but that wouldn't handle cases like /t:TargetThatDependsOnPublish. FYI @baronfel

[baronfel]

yeah, this is a sort of general problem we're hitting with all of these 'use publish to push better packaging practices'-style features - the gulf between dotnet X and dotnet msbuild /t:X grows over time. As I understand it @rainersigwald has been reluctant in the past (for good reason!) to add something like @(MSBuildDesiredTarget) as a known property, so we don't really have a good way to get out of this hole in a general fashion.

[agocke]

I think the _IsPublishing property is basically what I needed. I'm not sure much more than that would be necessary for my scenarios. I would prefer it to be "public", but otherwise it sounds good to me.

[agocke]

Aside -- could we just set IsPublishing in the Publish target? Is there some reason I'm missing why this isn't sufficient?

[dsplaisted]

Aside -- could we just set IsPublishing in the Publish target? Is there some reason I'm missing why this isn't sufficient?

In that case it wouldn't be set during MSBuild evaluation or in targets that run before publish. So I think in most cases it would be set way later than you would need to check it.

[agocke]

I see, in that case I could also set it to true in the Publish target in case of /t:Publish?

[nagilson]

I see, in that case I could also set it to true in the Publish target in case of /t:Publish?

No, see this discussion here: it (referring to _IsPublishing) needs to be defined as property. I don't know of any way to tell what the target is early enough for MSBuild evaluation to work properly. I hope this is helpful. #25991 (comment) @agocke