remove instio

Author: amuraru

MIGRATION_PLAN.md

@@ -0,0 +1,280 @@
+# Migration Plan: Istio Operator → Envoy Gateway
+
+## Overview
+
+This document outlines the complete migration plan to replace the Istio-based ingress controller with [Envoy Gateway](https://gateway.envoyproxy.io/) for Kafka external access in Koperator.
+
+**Migration Date**: 2025-11-03  
+**Last Commit**: 37d9feba - "Add e2e tests"  
+**Branch**: istio
+
+## Rationale
+
+- **Standardization**: Envoy Gateway uses Kubernetes Gateway API (standard)
+- **Simplification**: Remove dependency on Istio operator and custom client library
+- **Community Support**: Envoy Gateway is actively maintained by the Envoy community
+- **Reduced Complexity**: Eliminate custom mesh gateway deployments
+
+## Current State
+
+### Istio Components to Remove
+- `pkg/resources/istioingress/` - Complete Istio ingress implementation
+- `third_party/github.com/banzaicloud/istio-client-go` - Custom Istio client
+- `tests/e2e/test_istio_kafka_cluster.go` - Istio e2e tests
+- `config/samples/kraft/kafkacluster-kraft-with-istio.yaml` - Sample config
+- API types: `IstioIngressConfig` struct and related fields
+
+### Existing Envoy Support
+The codebase already has `pkg/resources/envoy/` which creates custom Envoy deployments. This will remain as-is for now (users can still use `ingressController: "envoy"`).
+
+---
+
+## Phase 1: Code Changes
+
+### 1.1 API Changes
+
+**File**: `api/v1beta1/kafkacluster_types.go`
+
+- [ ] Remove `IstioIngressConfig` struct (lines ~511-531)
+- [ ] Remove `IstioIngressConfig` field from `KafkaClusterSpec` (line ~205)
+- [ ] Remove `IstioIngressConfig` field from `IngressConfig` struct (line ~742)
+- [ ] Update `IngressController` enum validation to remove `istioingress` (line ~188)
+- [ ] Remove Istio-related constants:
+  - `defaultIstioIngressRequestResourceCpu`
+  - `defaultIstioIngressRequestResourceMemory`
+  - `defaultIstioIngressLimitResourceCpu`
+  - `defaultIstioIngressLimitResourceMemory`
+  - `DefaultIstioProxyImage`
+- [ ] Remove methods:
+  - `GetResources()` for IstioIngressConfig
+  - `GetReplicas()` for IstioIngressConfig
+  - `GetAnnotations()` for IstioIngressConfig
+  - `GetVirtualServiceAnnotations()` for IstioIngressConfig
+  - `GetLoadBalancerSourceRanges()` for IstioIngressConfig
+- [ ] Remove import: `github.com/banzaicloud/istio-client-go/pkg/networking/v1beta1`
+
+**File**: `api/v1beta1/zz_generated.deepcopy.go`
+- [ ] Regenerate after API changes
+
+### 1.2 Remove Istio Client Dependency
+
+**File**: `go.mod`
+- [ ] Remove `github.com/banzaicloud/istio-client-go v0.0.17` dependency
+- [ ] Remove replace directive: `github.com/banzaicloud/istio-client-go => ./third_party/github.com/banzaicloud/istio-client-go`
+- [ ] Run `go mod tidy`
+
+**Directory**: `third_party/github.com/banzaicloud/istio-client-go`
+- [ ] Delete entire directory
+
+### 1.3 Remove Istio Ingress Implementation
+
+**Directory**: `pkg/resources/istioingress/`
+- [ ] Delete entire directory containing:
+  - `istioingress.go` - Main reconciler
+  - `gateway.go` - Istio Gateway resources
+  - `virtualservice.go` - Istio VirtualService resources
+  - `meshgateway.go` - Custom mesh gateway deployment
+  - `istioingress_test.go` - Unit tests
+  - `meshgateway_test.go` - Unit tests
+
+**Directory**: `pkg/util/istioingress/`
+- [ ] Check if exists and delete if present
+
+### 1.4 Update Controller
+
+**File**: `controllers/kafkacluster_controller.go`
+- [ ] Remove import: `istioingress "github.com/banzaicloud/koperator/pkg/resources/istioingress"`
+- [ ] Remove from reconcilers list (line ~124): `istioingress.New(r.Client, instance),`
+- [ ] Remove any Istio-specific watches (check `SetupKafkaClusterWithManager`)
+
+### 1.5 Update Utility Functions
+
+**File**: `pkg/util/` (various files)
+- [ ] Search for Istio references: `grep -r "istio" pkg/util/`
+- [ ] Update or remove Istio-specific utility functions
+- [ ] Check `pkg/util/kafka/` for any Istio-related code
+
+---
+
+## Phase 2: Unit Tests
+
+### 2.1 Remove Istio Unit Tests
+
+**Files to Delete**:
+- [ ] `pkg/resources/istioingress/istioingress_test.go`
+- [ ] `pkg/resources/istioingress/meshgateway_test.go`
+- [ ] `controllers/tests/kafkacluster_controller_istioingress_test.go`
+
+### 2.2 Update Existing Tests
+
+**File**: `pkg/k8sutil/resource_test.go`
+- [ ] Remove Istio-related test cases (check for 278 new lines from last commit)
+
+**File**: `pkg/resources/envoy/envoy_test.go`
+- [ ] Review and ensure no Istio dependencies (303 new lines from last commit)
+
+**File**: `pkg/scale/scale_test.go`
+- [ ] Remove Istio scenarios if any
+
+**File**: `pkg/resources/nodeportexternalaccess/nodeportExternalAccess_test.go`
+- [ ] Review for Istio references (233 new lines from last commit)
+
+### 2.3 Run Unit Tests
+
+- [ ] Run: `make test`
+- [ ] Fix any compilation errors
+- [ ] Ensure all tests pass
+
+---
+
+## Phase 3: E2E Tests
+
+### 3.1 Remove Istio E2E Tests
+
+**Files to Delete**:
+- [ ] `tests/e2e/test_istio_kafka_cluster.go` (202 lines)
+- [ ] `config/samples/kraft/kafkacluster-kraft-with-istio.yaml` (245 lines)
+
+**File**: `tests/e2e/koperator_suite_test.go`
+- [ ] Remove Istio test invocations
+
+### 3.2 Update E2E Test Infrastructure
+
+**File**: `tests/e2e/const.go`
+- [ ] Remove Istio CRD kinds from `koperatorRelatedResourceKinds()` (lines 130-142):
+  - `virtualservices.networking.istio.io`
+  - `gateways.networking.istio.io`
+  - `destinationrules.networking.istio.io`
+  - `serviceentries.networking.istio.io`
+  - `workloadentries.networking.istio.io`
+  - `workloadgroups.networking.istio.io`
+  - `envoyfilters.networking.istio.io`
+  - `sidecars.networking.istio.io`
+  - `authorizationpolicies.security.istio.io`
+  - `peerauthentications.security.istio.io`
+  - `requestauthentications.security.istio.io`
+  - `telemetries.telemetry.istio.io`
+  - `wasmplugins.extensions.istio.io`
+
+**File**: `.github/workflows/e2e-test.yaml`
+- [ ] Remove Istio installation steps if any
+
+**File**: `.github/actions/kind-create/action.yaml`
+- [ ] Remove Istio setup if present
+
+### 3.3 Run E2E Tests
+
+- [ ] Run: `make e2e-test` or equivalent
+- [ ] Ensure tests pass without Istio
+
+---
+
+## Phase 4: Documentation & Cleanup
+
+### 4.1 Update CRDs
+
+**Files**:
+- [ ] `charts/kafka-operator/crds/kafkaclusters.yaml` - Regenerate
+- [ ] `config/base/crds/kafka.banzaicloud.io_kafkaclusters.yaml` - Regenerate
+- [ ] Run: `make generate manifests`
+
+### 4.2 Update Documentation
+
+**File**: `README.md`
+- [ ] Remove Istio references
+- [ ] Update ingress controller options (only `envoy` and `contour`)
+
+**File**: `docs/developer.md`
+- [ ] Update development setup (remove Istio)
+
+**File**: `ADOPTERS.md`
+- [ ] Review and update if needed
+
+### 4.3 Final Cleanup
+
+- [ ] Search for remaining "istio" references:
+  ```bash
+  grep -ri "istio" --exclude-dir=vendor --exclude-dir=.git --exclude="*.sum" --exclude="MIGRATION_PLAN.md"
+  ```
+- [ ] Update any remaining references
+- [ ] Run full test suite: `make test`
+- [ ] Run linting: `make lint`
+- [ ] Update CHANGELOG or release notes
+
+### 4.4 Verify Build
+
+- [ ] Run: `make build`
+- [ ] Run: `make docker-build`
+- [ ] Ensure no compilation errors
+
+---
+
+## Breaking Changes
+
+⚠️ **This is a BREAKING CHANGE for users**
+
+### Impact
+Users currently using `ingressController: "istioingress"` will need to migrate.
+
+### Migration Path for Users
+
+**Option 1: Use existing Envoy support**
+```yaml
+spec:
+  ingressController: "envoy"
+  envoyConfig:
+    # ... existing envoy config
+```
+
+**Option 2: Use Contour**
+```yaml
+spec:
+  ingressController: "contour"
+  contourIngressConfig:
+    # ... contour config
+```
+
+**Option 3: Future - Envoy Gateway** (not in this migration)
+Users who want Envoy Gateway will need to wait for future implementation or use the existing `envoy` option.
+
+---
+
+## Testing Checklist
+
+- [ ] Unit tests pass: `make test`
+- [ ] E2E tests pass: `make e2e-test`
+- [ ] Linting passes: `make lint`
+- [ ] Build succeeds: `make build`
+- [ ] Docker build succeeds: `make docker-build`
+- [ ] CRDs generated correctly: `make manifests`
+- [ ] No Istio references remain in codebase
+
+---
+
+## Rollback Plan
+
+If issues arise:
+1. Revert to commit `37d9feba` (before migration)
+2. Cherry-pick any critical fixes
+3. Re-evaluate migration approach
+
+---
+
+## Timeline
+
+- **Phase 1**: Code Changes - 2-3 hours
+- **Phase 2**: Unit Tests - 1-2 hours
+- **Phase 3**: E2E Tests - 1-2 hours
+- **Phase 4**: Documentation & Cleanup - 1 hour
+
+**Total Estimated Time**: 5-8 hours
+
+---
+
+## Notes
+
+- The existing `pkg/resources/envoy/` implementation remains unchanged
+- This migration only removes Istio support
+- Future work could add Envoy Gateway support as a new ingress controller type
+- Users have `envoy` and `contour` as alternatives
+