Typos and other errors often result in invalid presets in a template.
Coder would import these broken templates and present them to users when
they create workspaces. An unsuspecting user who chooses a broken preset
would then experience a failed workspace build with no obvious error
message.
This PR adds additional validation beyond what is possible in the
Terraform provider schema. Coder will now present a more helpful error
message to template authors when they upload a new template version:
<img width="1316" height="286" alt="Screenshot 2025-07-14 at 12 22 49"
src="https://github.com/user-attachments/assets/7f5f778f-d9ae-487a-95e2-f6f1ca604a9c"
/>
The frontend warning is less helpful right now, but I'd like to address
that in a follow-up since I need frontend help:
<img width="1102" height="616" alt="image"
src="https://github.com/user-attachments/assets/e838ffc8-ef4f-428d-9280-74fa0c491666"
/>
closes https://github.com/coder/coder/issues/17333
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Improved validation and error reporting for template presets,
providing clearer feedback when presets cannot be parsed or reference
undefined parameters.
* **Bug Fixes**
* Enhanced error handling during template version creation to better
detect and report issues with presets.
* **Tests**
* Added new tests to verify validation of both valid and invalid
Terraform presets during template version creation.
* Improved test reliability by enabling dynamic control over error
injection in database-related tests.
* **Chores**
* Updated a dependency to the latest version for improved stability and
features.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Sas Swart