Resource FQN tokens aren't resolved in a user friendly way

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cdktf & Language Versions

0.9.0. Any language.

Affected Resource(s)

Attempting to use .fqn on any resource when appending to it or using in an array (probably other cases as well). This mainly comes up when needing to use escape hatches.

Expected Behavior

Synthesized output is valid.

Actual Behavior

• Expected the start of an expression, but found an invalid expression token
• jsii.errors.JSIIError: Expected array type, got “<unresolved-token>”
• X is object with Y attributes

Important Factoids

Support for cross stack references caused a change in behavior. Previously .fqn actually return just a raw string (string token of string is the input string).

References

• https://discuss.hashicorp.com/t/python-escape-hatching-in-0-9-x/37202

[mutahhir]

Ah, I didn’t fully understand the core of the issue but went on from the last error message. My bad. Thanks for reopening @jsteinich, I’ll take another look soon.

To clarify: The main issue is the inability to use .fqn within the interpolated section of a string. The token system’s expectation that the resource fqn is being inserted into a non-interpolated terraform string is requiring users to jump through hoops to reference something that previously just required them to just do resource.fqn.

[paymog]

Thanks for looking into this @mutahir! I’ve long since resolved this issue and I don’t quite remember how I did it.

Though, I suspect that the reason I was seeing that error on 0.12 was because 0.12 requires running tsc prior to diff/deploy while 0.8 didn’t. I didn’t realize that until quite a few hours into debugging the upgrade.