Subtask 133.7: Architecture Quick Wins

[teemow]

Parent Issue

#133 - Epic: Architecture Improvements for Muster

Objective

Address small, low-risk improvements that can be completed quickly.

Tasks

1. Add Missing doc.go Files

Some packages lack doc.go files. Add documentation for:

• internal/template/doc.go
• internal/dependency/doc.go (verify exists)
• Any other missing packages

2. Split Files Exceeding 400 Lines

Per workspace rules, files should be under 400 lines. Current violations:

File	Lines	Action
internal/aggregator/server.go	1146	Covered by #133.2
internal/client/filesystem_client.go	1150	Split by domain
internal/client/kubernetes_client.go	500	Split by domain
internal/workflow/executor.go	931	Extract helpers

3. Remove Deprecated Functions

Remove backward-compatibility aliases:

• api.RegisterConfig() → use RegisterConfigHandler()
• api.GetConfig() → use GetConfigHandler()

4. Consolidate Test Utilities

Move scattered test helpers to internal/testing/:

• Review test files for duplicated mock implementations
• Consolidate into internal/testing/mock/

5. Update Import Organization

Ensure consistent import grouping:

1. Standard library
2. External dependencies
3. Internal packages

Run goimports -w . across codebase.

Files to Create

• internal/template/doc.go
• Any other missing doc.go files

Files to Modify

• internal/client/filesystem_client.go (split)
• internal/client/kubernetes_client.go (split)
• internal/workflow/executor.go (split)
• internal/api/config.go (remove aliases)
• Various test files (consolidate mocks)

Acceptance Criteria

• All packages have doc.go files
• No file exceeds 400 lines (except those covered by other issues)
• Deprecated aliases removed
• Test utilities consolidated
• Import organization consistent

Dependencies

Should be done early - low risk and sets foundation.

Risks

Low - these are mechanical changes.

Estimated Effort

Small (1-2 days)

[repairman29]

Hey there! This looks like something I could help with. I'd be happy to take a look and see what we can do.

(Found via Echeo)

[teemow]

Epic: giantswarm/giantswarm#36002 (Muster architecture improvements)

[QuentinBisson]

Task 4 audit findings

Reviewed internal/testing/ and inline mocks across *_test.go files. Conclusion: task 4 is largely already done — no meaningful consolidation PR to file.

State of internal/testing/mock/ — already populated:

• clock.go, handler.go, http_server.go, oauth_server.go, protected_mcp_server.go, server.go, types.go (plus tests)

Files in internal/testing/ root — all BDD-framework code (test runner, instance manager, scenario loader, reporters, test tools, types). These orchestrate the BDD scenarios; they are not pure mocks and don't belong in mock/.

Inline mock* types in *_test.go (across the codebase) — tied to package-local interfaces. Moving them to internal/testing/mock/ would require mock to import the parent package, breaking the package's own whitebox tests via import cycles.

Duplicates found: one. mockMCPServerManager exists in both internal/api/handlers_mcpserver_test.go and internal/server/oauth_http_test.go. They both implement api.MCPServerManagerHandler. Deduping would put the mock in internal/testing/mock/, but internal/api's test is whitebox (package api, accesses unexported handlerMutex/mcpServerManagerHandler), so it would still need its own copy. Net dedup: ~50 LOC saved at the cost of one more cross-package import — marginal, not worth a PR.

mockToolCaller in internal/workflow/executor_test.go and internal/services/instance_test.go look duplicated by name, but the interfaces differ (CallToolInternal vs CallTool, different signatures, different return types) — they're not actually duplicates.

Recommendation: mark task 4 done. The fixtures under internal/testing/fixtures/oauth/ are unused (//nolint:unused on every embed) — can be deleted in a separate small PR if desired.