Merge pull request #21 from stefanprodan/api-version

Add API versioning to Timoni's CUE definition

api/v1alpha1/selectors.go

@@ -0,0 +1,36 @@
+/*
+Copyright 2023 Stefan Prodan
+
+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 v1alpha1
+
+// Selector is an enumeration of the supported CUE paths known to Timoni.
+type Selector string
+
+// String returns the string representation of the Selector.
+func (s Selector) String() string {
+	return string(s)
+}
+
+const (
+	// APIVersionSelector is the CUE path for the Timoni's API version.
+	APIVersionSelector Selector = "timoni.apiVersion"
+
+	// ValuesSelector is the CUE path for the Timoni's module values.
+	ValuesSelector Selector = "values"
+
+	// ApplySelector is the CUE path for the Timoni's apply resource sets.
+	ApplySelector Selector = "timoni.apply"
+)

cmd/timoni/apply.go

@@ -183,6 +183,15 @@ func runApplyCmd(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("failed to build instance, error: %w", err)
 	}
 
+	apiVer, err := builder.GetAPIVersion(buildResult)
+	if err != nil {
+		return err
+	}
+
+	if apiVer != apiv1.GroupVersion.Version {
+		return fmt.Errorf("API version %s not supported, must be %s", apiVer, apiv1.GroupVersion.Version)
+	}
+
 	finalValues, err := builder.GetValues(buildResult)
 	if err != nil {
 		return fmt.Errorf("failed to extract values, error: %w", err)

cmd/timoni/build.go

@@ -133,6 +133,15 @@ func runBuildCmd(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("build failed, error: %w", err)
 	}
 
+	apiVer, err := builder.GetAPIVersion(buildResult)
+	if err != nil {
+		return err
+	}
+
+	if apiVer != apiv1.GroupVersion.Version {
+		return fmt.Errorf("API version %s not supported, must be %s", apiVer, apiv1.GroupVersion.Version)
+	}
+
 	applySets, err := builder.GetApplySets(buildResult)
 	if err != nil {
 		return fmt.Errorf("failed to extract objects, error: %w", err)

cmd/timoni/testdata/module/timoni.cue

@@ -1,6 +1,6 @@
 // Code generated by timoni. DO NOT EDIT.
-// Note that this file is required and should export
-// a stream of Kubernetes objects under the timoni.apply field.
+// Note that this file is required and should contain
+// the values schema and the timoni workflow.
 
 package main
 
@@ -13,23 +13,27 @@ import (
 // and validates them according to the Config schema.
 values: templates.#Config
 
-// Define the instance that outputs the Kubernetes resources.
-// At runtime, Timoni builds the instance and validates
-// the resulting resources according to their Kubernetes schema.
-instance: templates.#Instance & {
-	// The user-supplied values are merged with the
-	// default values at runtime by Timoni.
-	config: values
-	// The instance name and namespace tag values
-	// are injected at runtime by Timoni.
-	config: metadata: {
-		name:      string @tag(name)
-		namespace: string @tag(namespace)
+// Define how Timoni should build, validate and
+// apply the Kubernetes resources.
+timoni: {
+	apiVersion: "v1alpha1"
+
+	// Define the instance that outputs the Kubernetes resources.
+	// At runtime, Timoni builds the instance and validates
+	// the resulting resources according to their Kubernetes schema.
+	instance: templates.#Instance & {
+		// The user-supplied values are merged with the
+		// default values at runtime by Timoni.
+		config: values
+		// The instance name and namespace tag values
+		// are injected at runtime by Timoni.
+		config: metadata: {
+			name:      string @tag(name)
+			namespace: string @tag(namespace)
+		}
 	}
-}
 
-// Pass Kubernetes resources outputted by the instance
-// to Timoni's multi-step apply.
-timoni: {
+	// Pass Kubernetes resources outputted by the instance
+	// to Timoni's multi-step apply.
 	apply: all: [ for obj in instance.objects {obj}]
 }

examples/podinfo/timoni.cue

@@ -1,6 +1,6 @@
 // Code generated by timoni. DO NOT EDIT.
-// Note that this file is required and should export
-// a stream of Kubernetes objects under the timoni.apply field.
+// Note that this file is required and should contain
+// the values schema and the timoni workflow.
 
 package main
 
@@ -13,23 +13,27 @@ import (
 // and validates them according to the Config schema.
 values: templates.#Config
 
-// Define the instance that outputs the Kubernetes resources.
-// At runtime, Timoni builds the instance and validates
-// the resulting resources according to their Kubernetes schema.
-instance: templates.#Instance & {
-	// The user-supplied values are merged with the
-	// default values at runtime by Timoni.
-	config: values
-	// The instance name and namespace tag values
-	// are injected at runtime by Timoni.
-	config: metadata: {
-		name:      string @tag(name)
-		namespace: string @tag(namespace)
+// Define how Timoni should build, validate and
+// apply the Kubernetes resources.
+timoni: {
+	apiVersion: "v1alpha1"
+
+	// Define the instance that outputs the Kubernetes resources.
+	// At runtime, Timoni builds the instance and validates
+	// the resulting resources according to their Kubernetes schema.
+	instance: templates.#Instance & {
+		// The user-supplied values are merged with the
+		// default values at runtime by Timoni.
+		config: values
+		// The instance name and namespace tag values
+		// are injected at runtime by Timoni.
+		config: metadata: {
+			name:      string @tag(name)
+			namespace: string @tag(namespace)
+		}
 	}
-}
 
-// Pass Kubernetes resources outputted by the instance
-// to Timoni's multi-step apply.
-timoni: {
+	// Pass Kubernetes resources outputted by the instance
+	// to Timoni's multi-step apply.
 	apply: all: [ for obj in instance.objects {obj}]
 }

internal/engine/module_builder.go

@@ -17,37 +17,21 @@ limitations under the License.
 package engine
 
 import (
-	"bytes"
 	"fmt"
 	"os"
 	"path/filepath"
 
 	"cuelang.org/go/cue"
 	"cuelang.org/go/cue/cuecontext"
 	"cuelang.org/go/cue/load"
-	"cuelang.org/go/encoding/yaml"
-	"github.com/fluxcd/pkg/ssa"
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	apiv1 "github.com/stefanprodan/timoni/api/v1alpha1"
 )
 
 const (
 	defaultPackage    = "main"
-	defaultValuesName = "values"
 	defaultValuesFile = "values.cue"
-	defaultOutputExp  = "timoni.apply"
 )
 
-// ResourceSet is a named list of Kubernetes resource objects.
-type ResourceSet struct {
-
-	// Name of the object list.
-	Name string `json:"name"`
-
-	// Objects holds the list of Kubernetes objects.
-	// +optional
-	Objects []*unstructured.Unstructured `json:"objects,omitempty"`
-}
-
 // ModuleBuilder compiles CUE definitions to Kubernetes objects.
 type ModuleBuilder struct {
 	ctx        *cue.Context
@@ -87,7 +71,7 @@ func (b *ModuleBuilder) MergeValuesFile(overlays []string) error {
 		return err
 	}
 
-	cueGen := fmt.Sprintf("package %s\n%s: %v", b.pkgName, defaultValuesName, finalVal)
+	cueGen := fmt.Sprintf("package %s\n%s: %v", b.pkgName, apiv1.ValuesSelector, finalVal)
 
 	// overwrite the values.cue file with the merged values
 	if err := os.MkdirAll(b.moduleRoot, os.ModePerm); err != nil {
@@ -129,50 +113,24 @@ func (b *ModuleBuilder) Build() (cue.Value, error) {
 	return v, nil
 }
 
+// GetAPIVersion returns the list of API version of the Timoni's CUE definition.
+func (b *ModuleBuilder) GetAPIVersion(value cue.Value) (string, error) {
+	ver := value.LookupPath(cue.ParsePath(apiv1.APIVersionSelector.String()))
+	if ver.Err() != nil {
+		return "", fmt.Errorf("lookup %s failed, error: %w", apiv1.APIVersionSelector, ver.Err())
+	}
+	return ver.String()
+}
+
 // GetApplySets returns the list of Kubernetes unstructured objects to be applied in steps.
 func (b *ModuleBuilder) GetApplySets(value cue.Value) ([]ResourceSet, error) {
-	steps := value.LookupPath(cue.ParsePath(defaultOutputExp))
+	steps := value.LookupPath(cue.ParsePath(apiv1.ApplySelector.String()))
 	if steps.Err() != nil {
-		return nil, fmt.Errorf("lookup %s failed, error: %w", defaultOutputExp, steps.Err())
+		return nil, fmt.Errorf("lookup %s failed, error: %w", apiv1.ApplySelector, steps.Err())
 	}
 	return GetResources(steps)
 }
 
-// GetResources converts the CUE value to a list of ResourceSets.
-func GetResources(value cue.Value) ([]ResourceSet, error) {
-	var sets []ResourceSet
-	iter, _ := value.Fields(cue.Concrete(true))
-	for iter.Next() {
-		name := iter.Selector().String()
-		expr := iter.Value()
-		switch expr.Kind() {
-		case cue.ListKind:
-			items, err := expr.List()
-			if err != nil {
-				return nil, fmt.Errorf("listing objects for %s failed, error: %w", name, err)
-			}
-
-			data, err := yaml.EncodeStream(items)
-			if err != nil {
-				return nil, fmt.Errorf("encoding objects for %s failed, error: %w", name, err)
-			}
-
-			objects, err := ssa.ReadObjects(bytes.NewReader(data))
-			if err != nil {
-				return nil, fmt.Errorf("decoding objects for %s failed, error: %w", name, err)
-			}
-
-			sets = append(sets, ResourceSet{
-				Name:    name,
-				Objects: objects,
-			})
-		default:
-			return nil, fmt.Errorf("objects in %s are not of type cue.ListKind, got %v", name, value.Kind())
-		}
-	}
-	return sets, nil
-}
-
 // GetDefaultValues extracts the default values from the module.
 func (b *ModuleBuilder) GetDefaultValues() (string, error) {
 	filePath := filepath.Join(b.pkgPath, defaultValuesFile)
@@ -187,9 +145,9 @@ func (b *ModuleBuilder) GetDefaultValues() (string, error) {
 		return "", value.Err()
 	}
 
-	expr := value.LookupPath(cue.ParsePath(defaultValuesName))
+	expr := value.LookupPath(cue.ParsePath(apiv1.ValuesSelector.String()))
 	if expr.Err() != nil {
-		return "", fmt.Errorf("lookup %s failed, error: %w", defaultValuesName, expr.Err())
+		return "", fmt.Errorf("lookup %s failed, error: %w", apiv1.ValuesSelector, expr.Err())
 	}
 
 	return fmt.Sprintf("%v", expr.Eval()), nil
@@ -224,9 +182,9 @@ func (b *ModuleBuilder) GetModuleName() (string, error) {
 
 // GetValues extracts the values from the build result.
 func (b *ModuleBuilder) GetValues(value cue.Value) (string, error) {
-	expr := value.LookupPath(cue.ParsePath(defaultValuesName))
+	expr := value.LookupPath(cue.ParsePath(apiv1.ValuesSelector.String()))
 	if expr.Err() != nil {
-		return "", fmt.Errorf("lookup %s failed, error: %w", defaultValuesName, expr.Err())
+		return "", fmt.Errorf("lookup %s failed, error: %w", apiv1.ValuesSelector, expr.Err())
 	}
 
 	return fmt.Sprintf("%v", expr.Eval()), nil

internal/engine/module_builder_test.go

@@ -24,6 +24,8 @@ import (
 	"cuelang.org/go/cue"
 	"cuelang.org/go/cue/cuecontext"
 	. "github.com/onsi/gomega"
+
+	apiv1 "github.com/stefanprodan/timoni/api/v1alpha1"
 )
 
 func TestModuleBuilder(t *testing.T) {
@@ -47,28 +49,15 @@ func TestModuleBuilder(t *testing.T) {
 	val, err := mb.Build()
 	g.Expect(err).ToNot(HaveOccurred())
 
-	objects := val.LookupPath(cue.ParsePath("timoni.apply.all"))
+	apiVer, err := mb.GetAPIVersion(val)
+	g.Expect(err).ToNot(HaveOccurred())
+	g.Expect(apiVer).To(BeEquivalentTo(apiv1.GroupVersion.Version))
+
+	objects := val.LookupPath(cue.ParsePath(apiv1.ApplySelector.String() + ".all"))
 	g.Expect(objects.Err()).ToNot(HaveOccurred())
 
 	gold, err := ExtractValueFromFile(ctx, "testdata/module-golden/overlay.cue", "objects")
 	g.Expect(err).ToNot(HaveOccurred())
 
 	g.Expect(fmt.Sprintf("%v", objects)).To(BeEquivalentTo(fmt.Sprintf("%v", gold)))
 }
-
-func TestExtractBuildResult(t *testing.T) {
-	g := NewWithT(t)
-	ctx := cuecontext.New()
-
-	steps, err := ExtractValueFromFile(ctx, "testdata/api/apply-steps.cue", defaultOutputExp)
-	g.Expect(err).ToNot(HaveOccurred())
-
-	sets, err := GetResources(steps)
-	g.Expect(err).ToNot(HaveOccurred())
-
-	expectedNames := []string{"app", "addons", "tests"}
-	for s, set := range sets {
-		g.Expect(sets[s].Name).To(BeEquivalentTo(expectedNames[s]))
-		g.Expect(len(set.Objects)).To(BeEquivalentTo(2))
-	}
-}