Overview

As part of the OTE migration (WINC-1536), consolidate 23 template files into 4 Go templates using aggressive consolidation with code generators in openshift-tests-private. Validate the approach before future migration to origin.

Background

Current State:

• 23 static YAML files in openshift-tests-private/test/extended/testdata/winc/
• 9 Windows workload variations (windows_web_server.yaml, windows_web_server_byoh.yaml, etc.)
• 14 supporting templates (namespace, PVC, configmap, storage, OLM resources, etc.)
• Massive duplication and maintenance overhead

Problem:

• Nearly-identical files with minor variations
• Simple resources using template files unnecessarily
• String-based <placeholder> syntax is error-prone
• Difficult to maintain consistency across 23 files

Target State (OTP)

4 Go Template Files in test/extended/testdata/winc/:

1. windows_web_server_template.yaml - Parameterized Windows workload (replaces 9 files)
2. linux_web_server_template.yaml - Linux comparison workload
3. hpa_template.yaml - Horizontal Pod Autoscaler configuration
4. olm_bundle_template.yaml - OLM resources (replaces 3 files)

Code Generators in test/extended/util/winc/generators.go:

• GenerateNamespace() - replaces namespace.yaml
• GeneratePVC() - replaces pvc.yaml
• GenerateConfigMap() - replaces config-map.yaml
• GenerateDNSConfigMap() - replaces config-map-ip-dns.yaml
• GenerateProxyEnvVars() - replaces proxy_vars.yaml
• GenerateStorageClass() - replaces azure_storageclass.yaml + vsphere_storageclass.yaml
• GenerateWICDConfigMap() - replaces wicd_configmap.yaml
• GenerateImageDigestMirrorSet() - replaces stage-repo.yaml

Result: 23 files → 4 files (83% reduction)

Scope

This story includes:

• Create 4 Go templates in OTP testdata/winc/
• Implement 8 resource code generators in util/winc/
• Create WindowsWebServerConfig, HPAConfig, OLMBundleConfig structs
• Create template renderer functions (RenderWindowsWebServerTemplate(), RenderHPA(), RenderOLMBundle())
• Update all WINC tests to use new templates and code generators
• Validate with full test suite
• Remove 19 old static YAML files after validation
• Update README.md documentation

Out of Scope:

• MachineSet templates (separate story, blocked by WINC-1508)
• Migration to origin repository (future story, part of final OTE steps)

Implementation Approach

Phase 1: Create Templates and Generators

• Enhance existing windows_web_server_template.yaml
• Create linux_web_server_template.yaml, hpa_template.yaml, olm_bundle_template.yaml
• Implement generators.go with 8 resource generators
• Create windows_template.go with config structs and renderers

Phase 2: Update Tests

• Replace static YAML file references with template renderers
• Replace template file usage with code generators
• Update imports to github.com/openshift/openshift-tests-private/test/extended/util/winc

Phase 3: Validate and Clean Up

• Run full WINC test suite (go test ./test/extended/winc/...)
• Fix any test failures
• Remove 19 old static YAML files
• Update documentation

Why Code Generators > Template Files

For simple resources (namespace, PVC, configmap):

Old approach (template file):

# namespace.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: <namespace_name>

Requires: File I/O, placeholder replacement, error handling

New approach (code generator):

func GenerateNamespace(name string) string {
    return fmt.Sprintf(`apiVersion: v1
kind: Namespace
metadata:
  name: %s`, name)
}

Benefits:

• No template file to maintain
• Type-safe parameters
• IDE validation and autocomplete
• No file I/O overhead
• Compile-time validation

Location

All work in: openshift-tests-private repository

• Templates: test/extended/testdata/winc/
• Code: test/extended/util/winc/
• Tests: test/extended/winc/

Future Work

Migration to origin will happen later as one of the final steps of the OTE migration epic, after:

• All templates validated in OTP
• All tests passing with new approach
• WINC team comfortable with the consolidation
• Other OTE prerequisites completed

—

1. 1. 1. Acceptance Criteria

Templates and Code

• [ ] Exactly 4 YAML template files in test/extended/testdata/winc/
• [ ] generators.go created in test/extended/util/winc/ with 8+ resource generator functions
• [ ] windows_template.go created in test/extended/util/winc/ with config structs and renderers
• [ ] WindowsWebServerConfig struct created with all configuration options
• [ ] HPAConfig struct created
• [ ] OLMBundleConfig struct created
• [ ] NewDefaultWindowsWebServerConfig() function created
• [ ] RenderWindowsWebServerTemplate() function created
• [ ] RenderHPA() function created
• [ ] RenderOLMBundle() function created
• [ ] All 8 resource generators implemented (namespace, PVC, configmap, DNS configmap, proxy vars, storage class, WICD configmap, ImageDigestMirrorSet)

Testing and Validation

• [ ] All WINC tests updated to use new templates and code generators
• [ ] All WINC tests pass with new approach (go test ./test/extended/winc/...)
• [ ] Go templates verified to support all 9 Windows workload scenarios
• [ ] Code generators verified to replace 10 simple templates
• [ ] OLM bundle verified to replace 3 OLM templates
• [ ] All Go code compiles successfully

File Management

• [ ] 23 → 4 files (83% reduction achieved in OTP)
• [ ] Old static YAML files removed after validation
• [ ] MachineSet templates NOT touched (separate story)

Documentation

• [ ] README.md updated documenting new usage patterns
• [ ] Documentation includes migration path to origin for future story
• [ ] Code examples provided for common scenarios

Delivery

• [ ] PR submitted to openshift-tests-private repository
• [ ] PR reviewed and merged
• [ ] Unit tests added for generators (optional but recommended)

Risks and Mitigations

Risks

• Aggressive refactoring (23 → 4 files) may introduce issues
• New code generator approach needs validation
• Test updates across ~15-20 test cases
• Need to verify all scenarios still covered

Mitigations

• Templates already tested in OTP (proven working)
• Code generators are simple and testable
• Incremental test updates (one file at a time)
• Run full test suite after each update
• Keep old files until all tests pass
• Document all configuration options clearly
• Get review from WINC team before merging

Verification steps

1. Verify Files Created

cd openshift-tests-private/test/extended/testdata/winc/
ls -la *.yaml | grep -v machineset | wc -l
# Should show exactly 4 YAML files

2. Verify Go Code Exists

cd openshift-tests-private/test/extended/util/winc/
ls -la *.go
# Should show: generators.go, windows_template.go

3. Verify Code Compiles

cd openshift-tests-private
go build ./test/extended/util/winc/...
# Should compile without errors

4. Run Full Test Suite

cd openshift-tests-private
go test -v ./test/extended/winc/... -timeout 2h
# All tests should pass

5. Verify File Reduction

# Before: 23 template files
# After: 4 template files
# Reduction: 83% (19 files eliminated)

Example Usage 

Using Go Template

import "github.com/openshift/openshift-tests-private/test/extended/util/winc"

config := winc.NewDefaultWindowsWebServerConfig()
config.ImageName = "mcr.microsoft.com/windows/servercore:ltsc2022"
config.Replicas = 3
config.PVCName = "my-pvc"

manifest, err := winc.RenderWindowsWebServerTemplate(config)
// Apply manifest...

Using Code Generators

import "github.com/openshift/openshift-tests-private/test/extended/util/winc"

// Generate namespace (no template file needed!)
ns := winc.GenerateNamespace("winc-test")

// Generate PVC (no template file needed!)
pvc := winc.GeneratePVC("windows-data", "10Gi", "windows-sc")

// Generate StorageClass (no template file needed!)
sc := winc.GenerateStorageClass("windows-sc", winc.StorageClassAzure, nil)

// Apply manifests...

Notes

1. OTP-first approach - Validate consolidation in OTP before origin migration
2. Aggressive consolidation - 83% file reduction (23 → 4)
3. Code generation over templates - Simple resources generated in Go code (no file I/O)
4. Type safety - Struct-based configuration instead of string maps
5. No BYOH templates - BYOH is just a node selector configuration
6. Platform consolidation - Azure/vSphere StorageClass merged into one generator
7. OLM bundle - 3 OLM resources consolidated into one template
8. Test migration included - This story includes updating tests (not a separate story)
9. Origin migration later - Migration to origin happens as part of final OTE steps
10. Self-contained - All work happens in OTP, proves the approach works

Estimate Breakdown

• Create 4 Go templates: 2 points
• Implement 8 resource generators: 2 points
• Create config structs and renderers: 2 points
• Update all tests to use new approach: 4 points
• Run test suite and fix issues: 2 points
• Documentation and PR: 1 point

Total: 13 story points

Definition of Done

• All acceptance criteria met
• All WINC tests passing in CI
• Code reviewed and approved by WINC team
• PR merged to main branch
• Documentation updated
• 83% file reduction achieved and validated