Split main.go into logical packages

Author: alexandrst88

.gitignore

@@ -0,0 +1,9 @@
+*.tf
+.DS_Store
+.DS_Store?
+*.swp
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json

file_utils.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+
+	log "github.com/sirupsen/logrus"
+)
+
+func getAllFiles(ext string) ([]string, error) {
+	dir, err := os.Getwd()
+	checkError(err)
+	var files []string
+	log.Infof("Finding files in %q directory", dir)
+	files, err = filepath.Glob(tfFileExt)
+	checkError(err)
+
+	if len(files) == 0 {
+		log.Infof("No files with .tf extensions found in %q", dir)
+		os.Exit(0)
+	}
+	return files, nil
+}
+
+func fileExists(name string) bool {
+	if _, err := os.Stat(name); err == nil {
+		return true
+	}
+	return false
+}

generator.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"bufio"
+	"html/template"
+	"os"
+	"strings"
+	"sync"
+
+	log "github.com/sirupsen/logrus"
+)
+
+var replacer *strings.Replacer
+var varPrefix = "var."
+var tfFileExt = "*.tf"
+
+var dstFile = "./variables.tf"
+var varTemplate = template.Must(template.New("var_file").Parse(`{{range .}}
+variable "{{ . }}" {
+   description  = ""
+}
+ {{end}}
+`))
+
+func init() {
+	replacer = strings.NewReplacer(":", ".",
+		"]", "",
+		"}", "",
+		"{", "",
+		"\"", "",
+		")", "",
+		"(", "",
+		"[", "",
+		",", "",
+		"var.", "",
+		" ", "",
+	)
+}
+func main() {
+	if fileExists(dstFile) {
+		userPromt()
+	}
+
+	tfFiles, err := getAllFiles(tfFileExt)
+	checkError(err)
+	var wg sync.WaitGroup
+	messages := make(chan string)
+	wg.Add(len(tfFiles))
+	t := &terraformVars{}
+
+	for _, file := range tfFiles {
+		go func(file string) {
+			defer wg.Done()
+			fileHandle, _ := os.Open(file)
+			defer fileHandle.Close()
+			fileScanner := bufio.NewScanner(fileHandle)
+			for fileScanner.Scan() {
+				messages <- fileScanner.Text()
+			}
+		}(file)
+	}
+	go func() {
+		for text := range messages {
+			t.matchVarPref(text, varPrefix)
+		}
+	}()
+	wg.Wait()
+	f, err := os.Create(dstFile)
+	checkError(err)
+
+	err = varTemplate.Execute(f, t.Variables)
+	checkError(err)
+	log.Infof("Variables are generated to %q file", dstFile)
+
+}

generator_test.go

@@ -0,0 +1 @@
+package main

helpers.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	log "github.com/sirupsen/logrus"
+)
+
+func checkError(e error) {
+	if e != nil {
+		log.Fatal(e)
+	}
+}
+
+func containsElement(slice []string, value string) bool {
+	if len(slice) == 0 {
+		return false
+	}
+	for _, s := range slice {
+		if value == s {
+			return true
+		}
+	}
+	return false
+}
+
+func userPromt() {
+	var response string
+	log.Warnf("File %q already exists, type yes if you want replace", dstFile)
+	fmt.Print("-> ")
+	_, err := fmt.Scanln(&response)
+	checkError(err)
+	if response != "yes" {
+		os.Exit(0)
+	}
+}

main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"regexp"
+	"strings"
+)
+
+type terraformVars struct {
+	Variables []string
+}
+
+func (t *terraformVars) matchVarPref(row, varPrefix string) {
+	if strings.Contains(row, varPrefix) {
+		pattern := regexp.MustCompile(`var.([a-z?_]+)`)
+		match := pattern.FindAllStringSubmatch(row, 1)
+		if len(match) != 0 {
+			res := replacer.Replace(match[0][0])
+			if !containsElement(t.Variables, res) {
+				t.Variables = append(t.Variables, res)
+			}
+		}
+	}
+}