Hard gate #4: codified module boundaries as Go tests, so a new
contributor (or AI agent) can't silently land an import that crosses
a layer.
Boundaries enforced (one architecture_test.go per package):
- wsauth has no internal/* deps — auth leaf, must be unit-testable in
isolation
- models has no internal/* deps — pure-types leaf, reverse dep would
create cycles since most packages depend on models
- db has no internal/* deps — DB layer below business logic, must be
testable with sqlmock without spinning up handlers/provisioner
- provisioner does not import handlers or router — unidirectional
layering: handlers wires provisioner into HTTP routes; the reverse
is a cycle
Each test parses .go files in its package via go/parser (no x/tools
dep needed) and asserts forbidden import paths don't appear. Failure
messages name the rule, the offending file, and explain WHY the
boundary exists so the diff reviewer learns the rule.
Note: the original issue's first two proposed boundaries
(provisioner-no-DB, handlers-no-docker) don't match the codebase
today — provisioner already imports db (PR #2276 runtime-image
lookup) and handlers hold *docker.Client directly (terminal,
plugins, bundle, templates). I picked the four boundaries that
actually hold; the first two are aspirational and would need a
refactor before they could be codified.
Hand-tested by injecting a deliberate wsauth -> orgtoken violation:
the gate fires red with the rule message before merge.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>