cdktf sourced modules are unable to use list type variables sourced from another module's output

[celliott]

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cdktf & Language Versions

using typescript@4.2.3 and cdktf 0.2.0

Affected Resource(s)

cdktf importing of custom modules

Debug Output

https://gist.github.com/celliott/8fc7c7387ca2542ea7d50eebfe9d33c7

Expected Behavior

cdktf is able to generate working tf json for a module that uses type list variable source from another module's output

Actual Behavior

See gist for more detail

When I use a custom module that sources a list value from another module's output, tsc fails to compile with a type error. I see that custom sourced modules output types are always strings b/c they are references and not actual values.

• The custom module wrapper generated by cdktf typed the input as string[]; which matches the module
• The value sourced from the other module is a returned as a reference "${module.vpc.private_subnets_ids}". It is a string; not the actual value or string[]
• Alternatively, if I change the ts to pass an array, then it uses ["${module.vpc.private_subnets_ids}"]. tsc is happy but TF correctly reads that as a nested array; which causes the error.

Steps to Reproduce

See gist for more detail

• Add two sourced custom modules to cdktf.json
  • One must include an output with an array for a value
  • The other must use that value as an input typed list(string)
• Create a basic cdktf definition with both modules. One using the list output as an input
• $ cdktf get to generate the module wrappers
• $ tsc <- where I see error 1

Important Factoids

• Our modules are private or I would share a working example. If this bug is too confusing, then push back and I will create an example
• I haven't tested yet, but I am planning on using a data source lookup to get the vpc values to pass to the rds module to route around this issue

[jsteinich]

Looks like a duplicate of #287.
You could try using Token.asList on the module output to workaround.

[celliott]

closing as dupe of #287

[github-actions]

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