Extending android tauri configuration for multiple apps

[Vladsimir]

While searching for a way to handle building of different apps from the same codebase / repo, based on different environments (dev, stage, production) I stumbled on this section in the official guide. It gives an example of changing the tauri.conf.json file for different use-cases by extending it with another json file. That part works as described, the builder actually does run with merged configuration.

Relevant part of the main config:
{ "productName": "Test app", "identifier": "com.domain.test-app" }

What I put in the extended config:
{ "productName": "Test app stage", "identifier": "com.domain.test-app-stage" }

The command I'm running :
npm run tauri android build -- --config src-tauri/tauri.stage.conf.json

The problem is that running this script for my android build fails, as it seems the initialised tauri app just can't handle changes in the identifier property, as the file structure seems to be based on it.

I get the following error:
Error Project directory /path-to-my-project/src-tauri/gen/android/app/src/main/java/com/domain/test_app_stage does not exist. Did you update the package name inCargo.tomlor the bundle identifier intauri.conf.json > identifier? Save your changes, delete the gen/androidfolder and runtauri android initto recreate the Android project.

And it's true, that path doesn't exist. The tauri app during tauri android init created the file path based on the original identifier. The productName is also hard set in the strings.xml file, so changing it in the config makes no difference on the final build.

So I'm a bit confused. Based on what I understand so far on tauri, this example in the guilde just can't work for android. Am I missing something obvious?
What is the intended way of managing different instances of the same android app in tauri?

[FabianLars]

What is the intended way of managing different instances of the same android app in tauri?

For this to work you'll have to delete the gen/android dir and re-run android init as the error suggests. If you don't modify files in there for any native features this isn't really a problem, i know many that even gitignore that folder 🤷 I hope we can improve the whole situation here (iirc we wanted some kind of patch system so nobody has to commit the gen dir) but for now that's it.

[Vladsimir]

It's an option, though I was hoping for a solution that won't require me (or potentially other repo users) to delete and re-init the android app every time I want to build for a different environment. That guide section had me thinking something like this was possible for android as well.
Looks like the only way is to make a script that will:

1. Delete the gen folder
2. Edit the tauri.conf.json file with new identifier and productName properties
3. Edit the build.gradle.kts file in order to setup code signing
4. Override the relevant icons
5. Run the init command again

Is that something you'd recommend? Any thoughts in general? I'd like to implement this process to require as little manual user editing as possible, as any manual steps tend to get forgotten over time.
Thanks for the reply in any case.

[FabianLars]

Is that something you'd recommend?

Do i have to if there's no alternative? 🙃

Any thoughts in general?

Not too happy about it but i'm not in a position to fix it.

I'd like to implement this process to require as little manual user editing as possible, as any manual steps tend to get forgotten over time.

In that case i'd probably gitignore the gen/android folder and make the script(s) the standard way of building the app

p.s. in your script logic step 3 has to be after step 5. you can't edit a file that doesn't exist. (unless you plan to overwrite the generated one with prewritten on in step 6, then just ignore me)

[Vladsimir]

Thanks for the answers and yes I did mess up the order of the steps, but the idea of having a prewritten file is also a good one.