test(mesh): bootstrap builder for tf templating (#5)

xrel: 
- Kong/kong-mesh#7697
- split from:
Kong/terraform-provider-kong-mesh#13
- usage:
https://github.com/Kong/terraform-provider-kong-mesh/pull/13/files#diff-3985d78eaab3779db8be1d6749202977ccdc1d7b20b61aa699fe8eb78103b35bR67

---------

Signed-off-by: slonka <slonka@users.noreply.github.com>

Author: slonka

.github/workflows/test.yaml

@@ -0,0 +1,19 @@
+name: test
+concurrency:
+  group: test-${{ github.ref }}
+on:
+  pull_request:
+
+jobs:
+  unit:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 10
+    steps:
+      - name: Checkout Source Code
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Setup go
+        uses: actions/setup-go@0aaccfd150d50ccaeb58ebd88d36e91967a5f35b # v5.4.0
+        with:
+          go-version: '^1.24'
+      - run: make install-tools
+      - run: make test-all

Makefile

@@ -9,3 +9,7 @@ lint-all: ## lint all packages of the repository
 .PHONY: lint-fix-all
 lint-fix-all:
 	find . -name go.sum -exec dirname {} \; | xargs -I{} /bin/sh -c "cd {} && golangci-lint run --fix ./..."
+
+.PHONY: test-all
+test-all: ## lint all packages of the repository
+	find . -name go.sum -exec dirname {} \; | xargs -I{} /bin/sh -c "cd {} && go test ./... -v"

planmodifiers/suppress_zero_null/objectplanmodifier/supress_zero_null_modifier.go

@@ -62,7 +62,6 @@ func allNestedAttributesAreNull(obj basetypes.ObjectValue) bool {
 			// we conclude that not all attributes are null.
 			return false
 		}
-
 	}
 
 	// If we finish iterating without finding a non-null attribute,

tfbuilder/builder.go

@@ -0,0 +1,121 @@
+package tfbuilder
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"text/template"
+)
+
+type ProviderType string
+
+const (
+	KongMesh    ProviderType = "kong-mesh"
+	Konnect     ProviderType = "konnect"
+	KonnectBeta ProviderType = "konnect-beta"
+)
+
+type Builder struct {
+	provider         ProviderType
+	providerProperty ProviderType // optional
+	scheme           string
+	host             string
+	port             int
+	controlPlanes    map[string]*ControlPlane
+	meshes           map[string]*MeshBuilder
+	policies         map[string]*PolicyBuilder
+}
+
+func NewBuilder(provider ProviderType, scheme, host string, port int) *Builder {
+	return &Builder{
+		provider:      provider,
+		scheme:        scheme,
+		host:          host,
+		port:          port,
+		controlPlanes: make(map[string]*ControlPlane),
+		meshes:        make(map[string]*MeshBuilder),
+		policies:      make(map[string]*PolicyBuilder),
+	}
+}
+
+func (b *Builder) AddControlPlane(cp *ControlPlane) *Builder {
+	b.controlPlanes[cp.ResourceName] = cp
+	return b
+}
+
+func (b *Builder) AddMesh(mesh *MeshBuilder) *Builder {
+	b.meshes[mesh.ResourceName] = mesh
+	return b
+}
+
+func (b *Builder) RemoveMesh(name string) *Builder {
+	delete(b.meshes, name)
+	return b
+}
+
+func (b *Builder) AddPolicy(p *PolicyBuilder) *Builder {
+	b.policies[p.ResourceName] = p
+	return b
+}
+
+func (b *Builder) RemovePolicy(name string) *Builder {
+	delete(b.policies, name)
+	return b
+}
+
+func (b *Builder) WithProviderProperty(providerProperty ProviderType) *Builder {
+	b.providerProperty = providerProperty
+	return b
+}
+
+func (b *Builder) Build() string {
+	var sb strings.Builder
+
+	sb.WriteString(b.renderTemplate("provider.tmpl", map[string]interface{}{
+		"Provider":         b.provider,
+		"ProviderProperty": b.providerProperty,
+		"Scheme":           b.scheme,
+		"Host":             b.host,
+		"Port":             b.port,
+	}))
+	sb.WriteString("\n")
+
+	for _, cp := range b.controlPlanes {
+		sb.WriteString(cp.Render(b))
+		sb.WriteString("\n")
+	}
+
+	for _, mesh := range b.meshes {
+		sb.WriteString(mesh.Render(b))
+		sb.WriteString("\n")
+	}
+
+	for _, policy := range b.policies {
+		sb.WriteString(policy.Render(b))
+		sb.WriteString("\n")
+	}
+
+	return sb.String()
+}
+
+func (b *Builder) ResourceAddress(resourceType, resourceName string) string {
+	return fmt.Sprintf("%s_%s.%s", b.provider, resourceType, resourceName)
+}
+
+func (b *Builder) renderTemplate(file string, data interface{}) string {
+	tmplBytes, err := templatesFS.ReadFile("templates/" + file)
+	if err != nil {
+		panic(fmt.Errorf("failed to read template %s: %w", file, err))
+	}
+
+	tmpl, err := template.New(file).Parse(string(tmplBytes))
+	if err != nil {
+		panic(fmt.Errorf("failed to parse template: %w", err))
+	}
+
+	var out bytes.Buffer
+	if err := tmpl.Execute(&out, data); err != nil {
+		panic(fmt.Errorf("failed to render template: %w", err))
+	}
+	return out.String()
+}

tfbuilder/builder_test.go

@@ -0,0 +1,55 @@
+package tfbuilder_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/Kong/shared-speakeasy/tfbuilder"
+)
+
+func TestBuilder_KongMeshWithPolicy(t *testing.T) {
+	builder := tfbuilder.NewBuilder(tfbuilder.KongMesh, "http", "localhost", 5681)
+
+	// Add mesh
+	builder.AddMesh(
+		tfbuilder.NewMeshBuilder("default", "mesh-1").
+			WithSpec(`skip_creating_initial_policies = [ "*" ]`),
+	)
+
+	// Add policy
+	builder.AddPolicy(
+		tfbuilder.NewPolicyBuilder("mesh_traffic_permission", "allow_all", "allow-all", "MeshTrafficPermission").
+			WithMeshRef("kong-mesh_mesh.default.name").
+			WithDependsOn("kong-mesh_mesh.default").
+			WithLabels(map[string]string{
+				"kuma.io/mesh": "kong-mesh_mesh.default.name",
+			}).
+			WithSpecHCL(tfbuilder.AllowAllTrafficPermissionSpec),
+	)
+
+	actual := builder.Build()
+
+	goldenFile := filepath.Join("testdata", "expected_kong_mesh_with_policy.tf")
+
+	if updateGoldenFiles(t, goldenFile, actual) {
+		return
+	}
+
+	expected, err := os.ReadFile(goldenFile)
+	require.NoError(t, err, "reading golden file")
+
+	require.Equal(t, string(expected), actual)
+}
+
+func updateGoldenFiles(t *testing.T, goldenFile string, actual string) bool {
+	if os.Getenv("UPDATE_GOLDEN_FILES") == "1" {
+		err := os.WriteFile(goldenFile, []byte(actual), 0o600)
+		require.NoError(t, err, "updating golden file")
+		t.Logf("updated golden file: %s", goldenFile)
+		return true
+	}
+	return false
+}

tfbuilder/control_plane.go

@@ -0,0 +1,48 @@
+package tfbuilder
+
+import (
+	"bytes"
+	"fmt"
+	"text/template"
+)
+
+type ControlPlane struct {
+	ResourceName string
+	Name         string
+	Description  string
+}
+
+func NewControlPlane(resourceName, name, description string) *ControlPlane {
+	return &ControlPlane{
+		ResourceName: resourceName,
+		Name:         name,
+		Description:  description,
+	}
+}
+
+func (cp *ControlPlane) Render(provider *Builder) string {
+	data := map[string]interface{}{
+		"Provider":         provider.provider,
+		"ProviderProperty": provider.providerProperty,
+		"ResourceName":     cp.ResourceName,
+		"Name":             cp.Name,
+		"Description":      cp.Description,
+	}
+
+	tmplBytes, err := templatesFS.ReadFile("templates/control_plane.tmpl")
+	if err != nil {
+		panic(fmt.Errorf("failed to read control plane template: %w", err))
+	}
+
+	tmpl, err := template.New("control_plane").Parse(string(tmplBytes))
+	if err != nil {
+		panic(err)
+	}
+
+	var buf bytes.Buffer
+	if err := tmpl.Execute(&buf, data); err != nil {
+		panic(err)
+	}
+
+	return buf.String()
+}

tfbuilder/go.mod

@@ -0,0 +1,11 @@
+module github.com/Kong/shared-speakeasy/tfbuilder
+
+go 1.24.1
+
+require github.com/stretchr/testify v1.10.0
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

tfbuilder/go.sum

@@ -0,0 +1,10 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

tfbuilder/mesh.go

@@ -0,0 +1,66 @@
+package tfbuilder
+
+import (
+	"bytes"
+	"fmt"
+	"text/template"
+)
+
+type MeshBuilder struct {
+	ResourceName string
+	MeshName     string
+	DependsOn    []string
+	Spec         string
+	CPID         string // Optional
+}
+
+func NewMeshBuilder(resourceName, meshName string) *MeshBuilder {
+	return &MeshBuilder{
+		ResourceName: resourceName,
+		MeshName:     meshName,
+	}
+}
+
+func (m *MeshBuilder) WithSpec(spec string) *MeshBuilder {
+	m.Spec = spec
+	return m
+}
+
+func (m *MeshBuilder) WithCPID(cpID string) *MeshBuilder {
+	m.CPID = cpID
+	return m
+}
+
+func (m *MeshBuilder) WithDependsOn(deps ...string) *MeshBuilder {
+	m.DependsOn = append(m.DependsOn, deps...)
+	return m
+}
+
+func (m *MeshBuilder) Render(provider *Builder) string {
+	data := map[string]interface{}{
+		"Provider":         provider.provider,
+		"ProviderProperty": provider.providerProperty,
+		"ResourceName":     m.ResourceName,
+		"MeshName":         m.MeshName,
+		"DependsOn":        m.DependsOn,
+		"Spec":             m.Spec,
+		"CPID":             m.CPID,
+	}
+
+	tmplBytes, err := templatesFS.ReadFile("templates/mesh.tmpl")
+	if err != nil {
+		panic(fmt.Errorf("failed to read mesh template: %w", err))
+	}
+
+	tmpl, err := template.New("mesh").Parse(string(tmplBytes))
+	if err != nil {
+		panic(err)
+	}
+
+	var buf bytes.Buffer
+	if err := tmpl.Execute(&buf, data); err != nil {
+		panic(err)
+	}
+
+	return buf.String()
+}