Enabling production mode breaks backoffice

[nestalk]

Which Umbraco version are you using?

15.3.1

Bug summary

If I attempt to run an umbraco site in production mode as per the docs the backend stops working. Published pages will work but I cannot access the backend.

Specifics

Created a repo with the minimal reproduction https://github.com/nestalk/modetest.

If it is built in Release configuration and run with "ASPNETCORE_ENVIRONMENT": "Production" the backend will not load. But if in appsettings.Production.json you remove or change Umbraco:CMS:Runtime:Mode to another value the backend will load again.

The requests for the css and js files return 404 not found,

Steps to reproduce

run https://github.com/nestalk/modetest in Release build and in "ASPNETCORE_ENVIRONMENT": "Production"

Expected result / actual result

• Expected: backoffice loads
• Actual: blank page

[github-actions]

Hi there @nestalk!

Firstly, a big thank you for raising this issue. Every piece of feedback we receive helps us to make Umbraco better.

We really appreciate your patience while we wait for our team to have a look at this but we wanted to let you know that we see this and share with you the plan for what comes next.

• We'll assess whether this issue relates to something that has already been fixed in a later version of the release that it has been raised for.
• If it's a bug, is it related to a release that we are actively supporting or is it related to a release that's in the end-of-life or security-only phase?
• We'll replicate the issue to ensure that the problem is as described.
• We'll decide whether the behavior is an issue or if the behavior is intended.

We wish we could work with everyone directly and assess your issue immediately but we're in the fortunate position of having lots of contributions to work with and only a few humans who are able to do it. We are making progress though and in the meantime, we will keep you in the loop and let you know when we have any questions.

Thanks, from your friendly Umbraco GitHub bot 🤖 🙂

[AndyButland]

I had a look at this issue today and was able to replicate when running from a project locally, with production mode configured as per the documentation and running with:

dotnet run --configuration Release --environment Production

I found the reason was explained with this comment on some specific changes in a PR.

I've verified this - if you want to run non-development environment using the Production runtime mode from source you can, if you add this line to your Program.cs file:

builder.WebHost.UseStaticWebAssets();

There was a comment that:

We could add this to the documentation, but I guess it's really an edge-case and could potentially result in users adding this without knowing/fully understanding the implications and not removing/disabling it on production again

But given you've run into this I think it makes sense to add a note to the documentation about it. So I'll do that and close this issue.

[AndyButland]

PR for docs is here: umbraco/UmbracoDocs#7035

[nestalk]

thanks, i was testing it before i pushed it up to the server. So UseStaticWebAssets is only needed if you are running via visual studio and is not needed when running the published site on the server

[AndyButland]

Yes, that's my understanding.