Refactoring how to deal with shell variables.

pkg/vault-handler/dot_env.go

@@ -1,14 +1,16 @@
 package vaulthandler
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"path"
 	"strings"
 
 	log "github.com/sirupsen/logrus"
-	"github.com/subosito/gotenv"
 	shellescape "gopkg.in/alessio/shellescape.v1"
+	"mvdan.cc/sh/expand"
+	"mvdan.cc/sh/shell"
 )
 
 // DotEnv represents a .env file
@@ -21,29 +23,40 @@ type DotEnv struct {
 
 // Prepare by checking if dot-env (".env") file already exists, read it's contents.
 func (d *DotEnv) Prepare() error {
+	d.loadFiles()
+
 	if !FileExists(d.fullPath) {
 		d.logger.Info("Dot-env file is not found.")
 		return nil
 	}
-
-	d.logger.Info("Reading existing dot-env file contents.")
-	return d.readExisting()
+	if err := d.readExisting(); err != nil {
+		return err
+	}
+	return nil
 }
 
 // Write down dot-env file.
-func (d *DotEnv) Write() error {
+func (d *DotEnv) Write(dryRun bool) error {
 	var f *os.File
+	var escaped []string
 	var err error
 
-	d.loadFiles()
+	for k, v := range d.data {
+		d.logger.Infof("Adding key '%s' to dot-env file.", k)
+		escaped = append(escaped, fmt.Sprintf("%s=%s\n", k, shellescape.Quote(v)))
+	}
+
+	if dryRun {
+		d.logger.Info("[DRY-RUN] Skipping writting dot-env file.")
+		return nil
+	}
 
 	if f, err = os.OpenFile(d.fullPath, os.O_CREATE|os.O_RDWR, 0600); err != nil {
 		return err
 	}
 	defer f.Close()
-
-	for k, v := range d.data {
-		if _, err = f.WriteString(fmt.Sprintf("%s=%s\n", k, shellescape.Quote(v))); err != nil {
+	for _, s := range escaped {
+		if _, err = f.WriteString(s); err != nil {
 			return err
 		}
 	}
@@ -52,35 +65,41 @@ func (d *DotEnv) Write() error {
 
 // readExisting dot-env file, parsing out variable names and values.
 func (d *DotEnv) readExisting() error {
-	var f *os.File
+	var existing map[string]expand.Variable
 	var err error
 
-	if f, err = os.Open(d.fullPath); err != nil {
+	if existing, err = shell.SourceFile(context.TODO(), d.fullPath); err != nil {
 		return err
 	}
-	defer f.Close()
-	d.data = gotenv.Parse(f)
 
+	for k, v := range existing {
+		d.logger.Infof("Already existing dot-env variable '%s'", k)
+		d.put(k, v.String())
+	}
 	return nil
 }
 
-// envVarName format a variable name based on a File instance.
-func (d *DotEnv) envVarName(file *File) string {
-	name := fmt.Sprintf("%s_%s_%s", file.Group, file.Properties.Name, file.Properties.Extension)
-	return strings.ToUpper(name)
-}
-
 // loadFiles loop over array of Files, load contents
 func (d *DotEnv) loadFiles() {
 	for _, file := range d.files {
 		k := d.envVarName(file)
-		if _, found := d.data[k]; found {
-			d.logger.Warnf("Variable '%s' is already preset on '%s'!", k, d.fullPath)
-		}
 		v := string(file.Payload)
 		d.logger.Tracef("Adding entry on dot-env: '%s'='%s'", k, v)
-		d.data[k] = v
+		d.put(k, v)
+	}
+}
+
+// envVarName format a variable name based on a File instance.
+func (d *DotEnv) envVarName(file *File) string {
+	name := fmt.Sprintf("%s_%s_%s", file.Group, file.Properties.Name, file.Properties.Extension)
+	return strings.ToUpper(name)
+}
+
+func (d *DotEnv) put(k, v string) {
+	if _, found := d.data[k]; found {
+		d.logger.Warnf("Key '%s' is being overwritten!", k)
 	}
+	d.data[k] = v
 }
 
 // NewDotEnv creates a new instance.

pkg/vault-handler/dot_env_test.go

@@ -27,7 +27,7 @@ func TestDotEnvPrepare(t *testing.T) {
 }
 
 func TestDotEnvWrite(t *testing.T) {
-	err := dotEnv.Write()
+	err := dotEnv.Write(false)
 	assert.Nil(t, err)
 }