feat: First working version

.gitignore

@@ -1,4 +1,5 @@
 # Binaries for programs and plugins
+bin
 *.exe
 *.exe~
 *.dll

Makefile

@@ -0,0 +1,38 @@
+XC_OS="linux darwin"
+XC_ARCH="amd64 arm64"
+XC_PARALLEL="2"
+BIN="bin"
+SRC=$(shell find . -name "*.go")
+
+ifeq (, $(shell which gox))
+$(warning "could not find gox in $(PATH), run: go get github.com/mitchellh/gox")
+endif
+
+.PHONY: all build fmt test install_deps clean
+
+default: all
+
+all: fmt test build
+
+build: install_deps
+	gox \
+		-os=$(XC_OS) \
+		-arch=$(XC_ARCH) \
+		-parallel=$(XC_PARALLEL) \
+		-output=$(BIN)/{{.Dir}}_{{.OS}}_{{.Arch}} \
+		;
+
+fmt:
+	$(info ******************** checking formatting ********************)
+	@test -z $(shell gofmt -l $(SRC)) || (gofmt -d $(SRC); exit 1)
+
+test: install_deps
+	$(info ******************** running tests ********************)
+	go test -v ./...
+
+install_deps:
+	$(info ******************** downloading dependencies ********************)
+	go get -v ./...
+
+clean:
+	rm -rf $(BIN)

README.md

@@ -1,2 +1,3 @@
 # terraform-cleaner
+
 Tiny utility which detects unused variables in your terraform modules

cmd/root.go

@@ -0,0 +1,138 @@
+package cmd
+
+import (
+	"fmt"
+	"github.com/hashicorp/terraform-config-inspect/tfconfig"
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"regexp"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "terraform-cleaner",
+	Short: "Remove unused variables",
+	RunE:  rootCmdExec,
+}
+
+func rootCmdExec(cmd *cobra.Command, args []string) error {
+	dir := "."
+	if len(args) > 0 {
+		dir = args[0]
+	}
+	cmd.SilenceUsage = true
+
+	fUnusedOnly, _ := cmd.Flags().GetBool("unused-only")
+
+	modules, err := findTfModules(dir)
+	if err != nil {
+		return err
+	}
+
+	for path, _ := range modules {
+		stats, err := findVariablesUsage(path)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("Module: %s (%d variables found)\n", path, len(stats.variables))
+
+		for name, count := range stats.variables {
+			if fUnusedOnly && count > 0 {
+				continue
+			}
+			fmt.Printf("%s : %d\n", name, count)
+		}
+		fmt.Println("")
+	}
+
+	fmt.Printf("%d modules processed", len(modules))
+
+	return nil
+}
+
+type VariablesUsage struct {
+	variables map[string]int
+}
+
+func findVariablesUsage(path string) (VariablesUsage, error) {
+	out := VariablesUsage{variables: map[string]int{}}
+
+	module, diagnostics := tfconfig.LoadModule(path)
+	if diagnostics.HasErrors() {
+		return out, diagnostics.Err()
+	}
+
+	result, err := countVariables(path, module)
+	if err != nil {
+		return out, err
+	}
+
+	out.variables = result
+
+	return out, nil
+}
+
+func countVariables(path string, tfconfig *tfconfig.Module) (map[string]int, error) {
+	out := map[string]int{}
+
+	files, err := os.ReadDir(path)
+	if err != nil {
+		return out, err
+	}
+
+	for _, file := range files {
+		if filepath.Ext(file.Name()) == ".tf" {
+			data, err := os.ReadFile(filepath.Join(path, file.Name()))
+			if err != nil {
+				return out, err
+			}
+
+			content := string(data)
+
+			for variable, _ := range tfconfig.Variables {
+				regex := regexp.MustCompile(fmt.Sprintf(`var\.%s\W`, variable))
+				matches := regex.FindAllStringIndex(content, -1)
+
+				out[variable] += len(matches)
+			}
+
+		}
+	}
+
+	return out, err
+}
+
+func findTfModules(path string) (map[string]bool, error) {
+	var directories = make(map[string]bool)
+
+	err := filepath.WalkDir(path, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if filepath.Ext(path) == ".tf" {
+			module := filepath.Dir(path)
+			log.Debugf("Visited: %s\n", module)
+			if _, ok := directories[module]; !ok {
+				directories[module] = true
+			}
+		}
+		return nil
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return directories, nil
+}
+
+func Execute() error {
+	return rootCmd.Execute()
+}
+
+func init() {
+	rootCmd.Flags().Bool("unused-only", false, "Display only unused variables")
+}

cmd/root_test.go

@@ -0,0 +1,33 @@
+package cmd
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestFindTfModules(t *testing.T) {
+	t.Run("must found 3 modules", func(t *testing.T) {
+		path := "./testdata"
+
+		result, err := findTfModules(path)
+		assert.Equal(t, err, nil)
+		assert.Equal(t, len(result), 3)
+
+		assert.Contains(t, result, "testdata")
+		assert.Contains(t, result, "testdata/tf")
+		assert.Contains(t, result, "testdata/tf/1")
+	})
+}
+
+func TestFindVariablesUsage(t *testing.T) {
+	t.Run("should find all variables", func(t *testing.T) {
+		path := "./testdata/tf"
+
+		out, err := findVariablesUsage(path)
+		assert.Equal(t, err, nil)
+		assert.Equal(t, 1, out.variables["name"])
+		assert.Equal(t, 1, out.variables["region"])
+		assert.Equal(t, 1, out.variables["instance_ids"])
+		assert.Equal(t, 0, out.variables["legacy"])
+	})
+}

cmd/testdata/tf/main.tf

@@ -0,0 +1,23 @@
+terraform {
+  required_providers {
+    null = {
+      source = "hashicorp/null"
+      version = "3.2.1"
+    }
+  }
+}
+
+provider "null" {
+  region     = var.region
+}
+
+data "null_data_source" "values" {
+  inputs = var.name
+}
+
+resource "null_resource" "cluster" {
+  # Changes to any instance of the cluster requires re-provisioning
+  triggers = {
+    instance_ids = var.instance_ids
+  }
+}

cmd/testdata/tf/outputs.tf

@@ -0,0 +1,3 @@
+output "out" {
+  value = data.null_data_source.values.inputs
+}

cmd/testdata/tf/variables.tf

@@ -0,0 +1,16 @@
+variable "name" {
+  type = string
+  default = "terraform-cleaner"
+}
+
+variable "region" {
+  type = string
+  default = "ca-central-1"
+}
+
+variable "instance_ids" {
+  type = list(string)
+  default = ["i-123", "i-456"]
+}
+
+variable "legacy" {}

go.mod

@@ -0,0 +1,27 @@
+module github.com/sylwit/terraform-cleaner
+
+go 1.19
+
+require (
+	github.com/hashicorp/terraform-config-inspect v0.0.0-20230223165911-2d94e3d51111
+	github.com/sirupsen/logrus v1.9.0
+	github.com/spf13/cobra v1.6.1
+)
+
+require (
+	github.com/agext/levenshtein v1.2.2 // indirect
+	github.com/apparentlymart/go-textseg v1.0.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/google/go-cmp v0.3.0 // indirect
+	github.com/hashicorp/hcl v0.0.0-20170504190234-a4b07c25de5f // indirect
+	github.com/hashicorp/hcl/v2 v2.0.0 // indirect
+	github.com/inconshreveable/mousetrap v1.0.1 // indirect
+	github.com/mitchellh/go-wordwrap v1.0.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect˚
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/stretchr/testify v1.8.2 // indirect
+	github.com/zclconf/go-cty v1.1.0 // indirect
+	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f // indirect
+	golang.org/x/text v0.3.8 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)