Tuist Middleware or Custom Commands

[shahzadmajeed]

Goal:

We want to run custom linting rules on project structure using tuist graph which will ensure that our dependencies are setup correctly. Certain dependencies are not imported in some particular modules to avoid an issue for downstream consumers etc… There are many other applications (like structuring a white label project for a specific app or generating code etc.)

Proposals:

1. Middlewares - A tuist manifest awaitable handler that tuist executes before each generate command and the handler returns a success or throws an error. If error, tuist prints it and terminates the process

let project = Project(
   ....,
   middleware: { graph in
           /// We probably also want to import SwiftSyntax or other internal libraries
           await validateGraph(graph)
   } 
)

2. Custom Tuist Commands - Allow consumers to implement their own custom tuist commands (something like plugins but it doesn’t need to be a separate swift package of itself)

3. Pre/Post Hooks - At callsite we can can pass the command a custom script hook that the command can call before or after the (generate) command is executed

[marekfort]

Hey @shahzadmajeed

Thanks for bringing this up

@shahzadmajeed

Middlewares - A tuist manifest awaitable handler that tuist executes before each generate command and the handler returns a success or throws an error. If error, tuist prints it and terminates the process

The properties of Project must be Codable, so passing in a function is a no-go.

As for 2. and 3., we have considered both options in the past, but I personally don’t see a ton of value in having hooks or extending the tuist CLI with custom commands over wrapping tuist and tuist generate in your own scripts that your team would be using.

From the three, pre- and post-generation hooks feel like the best option if we do decide to go ahead with something here, but again, I wonder how much of an improvement that is over having a custom script such as:

# pre-hook
echo "Here do pre-generate work"
tuist generate
# post-hook
echo "Here do post-generate work"

[shahzadmajeed]

Thanks for quick response Marek.

For scripts/hooks, the question is how do we get access to the graph? Would it be manual via. graph package? Isn’t project generated already if we want to use XcodeGraph?