feat: Migrate provider-template from cluster scope to namespaced scope (#132)

This PR migrates the provider template from Crossplane v1 to v2. It also implements Gate feature that introduced from v2 to control resources to install to the cluster.

Key changes:

API Updates:
- Consolidate ProviderConfig and related types into unified types.go
- Add namespaced ProviderConfig alongside cluster-scoped ClusterProviderConfig
- Add namespaced ProviderConfigUsage and ClusterProviderConfigUsage
- Update MyType to use namespaced scope by default
- Remove deprecated StoreConfig (external secret stores no longer supported in v2)
- Migrate to crossplane-runtime v2.0.0 with breaking changes

Controller Enhancements:
- Implement safe-start pattern with SetupGated functions
- Add gate-based controller registration to wait for CRDs
- Add customresourcesgate controller to watch for CRD availability
- Update credential extraction to support both namespaced and cluster-scoped configs
- Support dynamic ProviderConfig reference kind switching
- Remove deprecated feature flag system in favor of runtime feature package
- Remove deprecated non-gated Setup function from register.go
- Rename internal/controller/template.go to register.go for clarity

Template Updates:
- Add SetupGated function to controller template for safe-start support
- Update controller template to use v1alpha1 instead of dynamic API version
- Fix typo: WithExternalConnecter -> WithExternalConnector
- Remove unused ConnectionPublisher initialization
- Add missing xpv1 import for ResourceStatus in type templates
- Change Status to use xpv1.ResourceStatus instead of xpv2.ResourceStatus
- Improve error constant alignment and formatting

Dependencies:
- Upgrade to crossplane-runtime v2.0.0
- Add k8s.io/apiextensions-apiserver for CRD scheme registration
- Update controller-runtime to v0.21.0
- Update Go toolchain to 1.24.5

Examples and Documentation:
- Update code generation templates for namespaced resources
- Add namespace field to example manifests
- Update ProviderConfig examples to demonstrate new structure
- Remove StoreConfig examples
- Update README.md to include step for registering new types in SetupGated
- Fix capitalization: "Template provider" -> "template provider"
- Fix capitalization: "group Sample" -> "group sample"

Package Metadata:
- Add safe-start capability to crossplane.yaml package metadata

This migration provides better resource isolation, simplified authentication
patterns, and improved startup reliability through the safe-start mechanism.

Signed-off-by: Chuan-Yen Chiang <[email protected]>

Author: cychiang

README.md

@@ -27,6 +27,7 @@ with the following features that are meant to be refactored:
 5. Replace the *sample* group with your new group in apis/{provider}.go
 5. Replace the *mytype* type with your new type in internal/controller/{provider}.go
 5. Replace the default controller and ProviderConfig implementations with your own
+5. Register your new type into `SetupGated` function in `internal/controller/register.go`
 5. Run `make reviewable` to run code generation, linters, and tests.
 5. Run `make build` to build the provider.
 

apis/generate.go

@@ -1,5 +1,3 @@
-//go:build generate
-
 /*
 Copyright 2025 The Crossplane Authors.
 
@@ -29,9 +27,3 @@ limitations under the License.
 //go:generate go run -tags generate github.com/crossplane/crossplane-tools/cmd/angryjet generate-methodsets --header-file=../hack/boilerplate.go.txt ./...
 
 package apis
-
-import (
-	_ "sigs.k8s.io/controller-tools/cmd/controller-gen" //nolint:typecheck
-
-	_ "github.com/crossplane/crossplane-tools/cmd/angryjet" //nolint:typecheck
-)

apis/sample/sample.go

@@ -14,5 +14,5 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-// Package sample contains group Sample API versions
+// Package sample contains group sample API versions
 package sample

apis/sample/v1alpha1/groupversion_info.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-// Package v1alpha1 contains the v1alpha1 group Sample resources of the Template provider.
+// Package v1alpha1 contains the v1alpha1 group Sample resources of the template provider.
 // +kubebuilder:object:generate=true
 // +groupName=sample.template.crossplane.io
 // +versionName=v1alpha1

apis/sample/v1alpha1/mytype_types.go

@@ -22,7 +22,8 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 
-	xpv1 "github.com/crossplane/crossplane-runtime/apis/common/v1"
+	xpv1 "github.com/crossplane/crossplane-runtime/v2/apis/common/v1"
+	xpv2 "github.com/crossplane/crossplane-runtime/v2/apis/common/v2"
 )
 
 // MyTypeParameters are the configurable fields of a MyType.
@@ -38,8 +39,8 @@ type MyTypeObservation struct {
 
 // A MyTypeSpec defines the desired state of a MyType.
 type MyTypeSpec struct {
-	xpv1.ResourceSpec `json:",inline"`
-	ForProvider       MyTypeParameters `json:"forProvider"`
+	xpv2.ManagedResourceSpec `json:",inline"`
+	ForProvider              MyTypeParameters `json:"forProvider"`
 }
 
 // A MyTypeStatus represents the observed state of a MyType.
@@ -56,7 +57,7 @@ type MyTypeStatus struct {
 // +kubebuilder:printcolumn:name="EXTERNAL-NAME",type="string",JSONPath=".metadata.annotations.crossplane\\.io/external-name"
 // +kubebuilder:printcolumn:name="AGE",type="date",JSONPath=".metadata.creationTimestamp"
 // +kubebuilder:subresource:status
-// +kubebuilder:resource:scope=Cluster,categories={crossplane,managed,template}
+// +kubebuilder:resource:scope=Namespaced,categories={crossplane,managed,template}
 type MyType struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`

apis/sample/v1alpha1/zz_generated.deepcopy.go

@@ -14,4 +14,8 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+// Package v1alpha1 contains the core resources of the Template provider.
+// +kubebuilder:object:generate=true
+// +groupName=template.crossplane.io
+// +versionName=v1alpha1
 package v1alpha1