Add initializer package to reduce per linter boilerplate

Author: JoelSpeed

pkg/analysis/commentstart/initializer.go

@@ -17,34 +17,21 @@ package commentstart
 
 import (
 	"golang.org/x/tools/go/analysis"
+	"sigs.k8s.io/kube-api-linter/pkg/analysis/initializer"
 	"sigs.k8s.io/kube-api-linter/pkg/config"
 )
 
 // Initializer returns the AnalyzerInitializer for this
 // Analyzer so that it can be added to the registry.
-func Initializer() initializer {
-	return initializer{}
-}
-
-// intializer implements the AnalyzerInitializer interface.
-type initializer struct{}
-
-// Name returns the name of the Analyzer.
-func (initializer) Name() string {
-	return name
+func Initializer() initializer.AnalyzerInitializer {
+	return initializer.NewInitializer(
+		name,
+		initAnalyzer,
+		true,
+	)
 }
 
 // Init returns the intialized Analyzer.
-func (initializer) Init(cfg config.LintersConfig) (*analysis.Analyzer, error) {
+func initAnalyzer(cfg config.LintersConfig) (*analysis.Analyzer, error) {
 	return Analyzer, nil
 }
-
-// IsConfigurable determines whether or not the Analyzer provides configuration options.
-func (initializer) IsConfigurable() bool {
-	return false
-}
-
-// Default determines whether this Analyzer is on by default, or not.
-func (initializer) Default() bool {
-	return true
-}

pkg/analysis/conditions/initializer.go

@@ -20,38 +20,30 @@ import (
 
 	"golang.org/x/tools/go/analysis"
 	"k8s.io/apimachinery/pkg/util/validation/field"
+	"sigs.k8s.io/kube-api-linter/pkg/analysis/initializer"
 	"sigs.k8s.io/kube-api-linter/pkg/config"
 )
 
 // Initializer returns the AnalyzerInitializer for this
 // Analyzer so that it can be added to the registry.
-func Initializer() initializer {
-	return initializer{}
+func Initializer() initializer.AnalyzerInitializer {
+	return initializer.NewConfigurableInitializer(
+		name,
+		initAnalyzer,
+		true,
+		validateConfig,
+	)
 }
 
-// intializer implements the AnalyzerInitializer interface.
-type initializer struct{}
-
-// Name returns the name of the Analyzer.
-func (initializer) Name() string {
-	return name
-}
-
-// Init returns the intialized Analyzer.
-func (initializer) Init(cfg config.LintersConfig) (*analysis.Analyzer, error) {
+func initAnalyzer(cfg config.LintersConfig) (*analysis.Analyzer, error) {
 	return newAnalyzer(cfg.Conditions), nil
 }
 
-// IsConfigurable determines whether or not the Analyzer provides configuration options.
-func (initializer) IsConfigurable() bool {
-	return true
-}
-
-// ValidateConfig implements validation of the conditions linter config.
-func (initializer) ValidateConfig(cfg any, fldPath *field.Path) field.ErrorList {
+// validateConfig implements validation of the conditions linter config.
+func validateConfig(cfg any, fldPath *field.Path) field.ErrorList {
 	cc, ok := cfg.(config.ConditionsConfig)
 	if !ok {
-		return field.ErrorList{field.InternalError(fldPath, fmt.Errorf("incorrect type for passed configuration: %T", cfg))}
+		return field.ErrorList{field.InternalError(fldPath, initializer.NewIncorrectTypeError(cfg))}
 	}
 
 	fieldErrors := field.ErrorList{}
@@ -76,8 +68,3 @@ func (initializer) ValidateConfig(cfg any, fldPath *field.Path) field.ErrorList
 
 	return fieldErrors
 }
-
-// Default determines whether this Analyzer is on by default, or not.
-func (initializer) Default() bool {
-	return true
-}

pkg/analysis/duplicatemarkers/initializer.go

@@ -17,36 +17,21 @@ package duplicatemarkers
 
 import (
 	"golang.org/x/tools/go/analysis"
+	"sigs.k8s.io/kube-api-linter/pkg/analysis/initializer"
 	"sigs.k8s.io/kube-api-linter/pkg/config"
 )
 
 // Initializer returns the AnalyzerInitializer for this
 // Analyzer so that it can be added to the registry.
-func Initializer() initializer {
-	return initializer{}
+func Initializer() initializer.AnalyzerInitializer {
+	return initializer.NewInitializer(
+		name,
+		initAnalyzer,
+		true,
+	)
 }
 
-// intializer implements the AnalyzerInitializer interface.
-type initializer struct{}
-
-// Name returns the name of the Analyzer.
-func (initializer) Name() string {
-	return name
-}
-
-// Init returns the intialized Analyzer.
-func (initializer) Init(cfg config.LintersConfig) (*analysis.Analyzer, error) {
+// initAnalyzer returns the intialized Analyzer.
+func initAnalyzer(cfg config.LintersConfig) (*analysis.Analyzer, error) {
 	return Analyzer, nil
 }
-
-// IsConfigurable determines whether or not the Analyzer provides configuration options.
-func (initializer) IsConfigurable() bool {
-	return false
-}
-
-// Default determines whether this Analyzer is on by default, or not.
-func (initializer) Default() bool {
-	// Duplicated markers are a sign of bad code, and should be avoided.
-	// This is a good rule to have on by default.
-	return true
-}

pkg/analysis/initializer/errors.go

@@ -0,0 +1,31 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package initializer
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	errIncorrectType = errors.New("incorrect type for passed configuration")
+)
+
+// NewIncorrectTypeError returns a new error indicating that the provided configuration
+// is of the incorrect type.
+func NewIncorrectTypeError(cfg any) error {
+	return fmt.Errorf("%w: %T", errIncorrectType, cfg)
+}

pkg/analysis/initializer/initializer.go

@@ -0,0 +1,122 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package initializer
+
+import (
+	"golang.org/x/tools/go/analysis"
+	"k8s.io/apimachinery/pkg/util/validation/field"
+	"sigs.k8s.io/kube-api-linter/pkg/config"
+)
+
+// InitializerFunc is a function that initializes an Analyzer.
+type InitializerFunc func(config.LintersConfig) (*analysis.Analyzer, error)
+
+// ValidateFunc is a function that validates the configuration for an Analyzer.
+type ValidateFunc func(any, *field.Path) field.ErrorList
+
+// AnalyzerInitializer is used to initialize analyzers.
+type AnalyzerInitializer interface {
+	// Name returns the name of the analyzer initialized by this initializer.
+	Name() string
+
+	// Init returns the newly initialized analyzer.
+	// It will be passed the complete LintersConfig and is expected to rely only on its own configuration.
+	Init(config.LintersConfig) (*analysis.Analyzer, error)
+
+	// IsConfigurable determines whether or not the initializer expects to be provided a config.
+	// When true, the initializer should also match the ConfigurableAnalyzerInitializer interface.
+	IsConfigurable() bool
+
+	// Default determines whether the inializer intializes an analyzer that should be
+	// on by default, or not.
+	Default() bool
+}
+
+// ConfigurableAnalyzerInitializer is an analyzer initializer that also has a configuration.
+// This means it can validate its config.
+type ConfigurableAnalyzerInitializer interface {
+	AnalyzerInitializer
+
+	// ValidateConfig will be called during the config validation phase and is used to validate
+	// the provided config for the linter.
+	ValidateConfig(any, *field.Path) field.ErrorList
+}
+
+// NewInitializer construct a new initializer for initializing an Analyzer.
+func NewInitializer(name string, initFunc InitializerFunc, isDefault bool) AnalyzerInitializer {
+	return initializer{
+		name:      name,
+		initFunc:  initFunc,
+		isDefault: isDefault,
+	}
+}
+
+// NewConfigurableInitializer constructs a new initializer for intializing a
+// configurable Analyzer.
+func NewConfigurableInitializer(name string, initFunc InitializerFunc, isDefault bool, validateFunc ValidateFunc) ConfigurableAnalyzerInitializer {
+	return configurableInitializer{
+		initializer: initializer{
+			name:      name,
+			initFunc:  initFunc,
+			isDefault: isDefault,
+		},
+		validateFunc: validateFunc,
+	}
+}
+
+type initializer struct {
+	name      string
+	initFunc  InitializerFunc
+	isDefault bool
+}
+
+// Name returns the name of the initializer.
+func (i initializer) Name() string {
+	return i.name
+}
+
+// Init returns a newly initializr analyzer.
+func (i initializer) Init(cfg config.LintersConfig) (*analysis.Analyzer, error) {
+	return i.initFunc(cfg)
+}
+
+// IsConfigurable determines whether or not to expect this initializer to
+// be able to be configured with custom configuration.
+func (i initializer) IsConfigurable() bool {
+	return false
+}
+
+// Default determines whether this initializer should be enabled by default or not.
+func (i initializer) Default() bool {
+	return i.isDefault
+}
+
+type configurableInitializer struct {
+	initializer
+
+	validateFunc ValidateFunc
+}
+
+// IsConfigurable determines whether or not to expect this initializer to
+// be able to be configured with custom configuration.
+func (i configurableInitializer) IsConfigurable() bool {
+	return true
+}
+
+// ValidateConfig validates the configuration for the initializer.
+func (i configurableInitializer) ValidateConfig(cfg any, fld *field.Path) field.ErrorList {
+	return i.validateFunc(cfg, fld)
+}

pkg/analysis/integers/initializer.go

@@ -17,34 +17,20 @@ package integers
 
 import (
 	"golang.org/x/tools/go/analysis"
+	"sigs.k8s.io/kube-api-linter/pkg/analysis/initializer"
 	"sigs.k8s.io/kube-api-linter/pkg/config"
 )
 
 // Initializer returns the AnalyzerInitializer for this
 // Analyzer so that it can be added to the registry.
-func Initializer() initializer {
-	return initializer{}
+func Initializer() initializer.AnalyzerInitializer {
+	return initializer.NewInitializer(
+		name,
+		initAnalyzer,
+		true,
+	)
 }
 
-// intializer implements the AnalyzerInitializer interface.
-type initializer struct{}
-
-// Name returns the name of the Analyzer.
-func (initializer) Name() string {
-	return name
-}
-
-// Init returns the intialized Analyzer.
-func (initializer) Init(cfg config.LintersConfig) (*analysis.Analyzer, error) {
+func initAnalyzer(cfg config.LintersConfig) (*analysis.Analyzer, error) {
 	return Analyzer, nil
 }
-
-// IsConfigurable determines whether or not the Analyzer provides configuration options.
-func (initializer) IsConfigurable() bool {
-	return false
-}
-
-// Default determines whether this Analyzer is on by default, or not.
-func (initializer) Default() bool {
-	return true
-}