Merge pull request #20 from Droplr/feat-formatDotenv

Allow to output in a dotenv format to create .env files

README.md

@@ -33,7 +33,10 @@ $ export DB_USERNAME=$'Username'
 $ export DB_PASSWORD=$'SecretPassword'
 ```
 
-You can also pass the `--recursive` flag.  When specified, aws-env will recursively fetch parameters starting from the base path specified in 
+### Optional Flags
+
+*--recursive*
+You can pass the `--recursive` flag.  When specified, aws-env will recursively fetch parameters starting from the base path specified in
 `AWS_ENV_PATH`.  For the exported environment variables, any `/` characters from sub-paths will be converted to `_` characters.  For example:
 
 With the following parameters:
@@ -44,10 +47,27 @@ $ aws ssm put-parameter --name /prod/my-app/db1/DB_PASSWORD --value "OtherSecret
 
 `eval $(AWS_ENV_PATH=/prod/my-app/ AWS_REGION=us-west-2 ./aws-env --recursive)` will output:
 ```
-$ export db0_DB_PASSWORD=$'SecretPassword'
-$ export db1_DB_PASSWORD=$'OtherSecretPassword'
+export db0_DB_PASSWORD=$'SecretPassword'
+export db1_DB_PASSWORD=$'OtherSecretPassword'
 ```
 
+*--format*
+
+Specify output format of parameters.
+
+* exports (default) - export as environmental variables ready to be eval(...)
+* dotenv - used for generating dotenv files
+
+`AWS_ENV_PATH=/prod/my-app/ AWS_REGION=us-west-2 ./aws-env --format=dotenv` will output:
+```
+FOO="bar"
+ACME="zaz"
+```
+
+...which then can be easily used to create .env file:
+
+`AWS_ENV_PATH=/prod/my-app/ AWS_REGION=us-west-2 ./aws-env --format=dotenv > .env`
+
 ## Example Dockerfile
 
 ```

aws-env.go

@@ -1,14 +1,19 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ssm"
 	"log"
 	"os"
 	"strings"
-        "flag"
+)
+
+const (
+	formatExports = "exports"
+	formatDotenv  = "dotenv"
 )
 
 func main() {
@@ -17,13 +22,19 @@ func main() {
 		return
 	}
 
-        recursivePtr := flag.Bool("recursive", false, "recursively process parameters on path")
-        flag.Parse()
+	recursivePtr := flag.Bool("recursive", false, "recursively process parameters on path")
+	format := flag.String("format", formatExports, "output format")
+	flag.Parse()
+
+	if *format == formatExports || *format == formatDotenv {
+	} else {
+		log.Fatal("Unsupported format option. Must be 'exports' or 'dotenv'")
+	}
 
 	sess := CreateSession()
 	client := CreateClient(sess)
 
-	ExportVariables(client, os.Getenv("AWS_ENV_PATH"), *recursivePtr, "")
+	ExportVariables(client, os.Getenv("AWS_ENV_PATH"), *recursivePtr, *format, "")
 }
 
 func CreateSession() *session.Session {
@@ -34,12 +45,12 @@ func CreateClient(sess *session.Session) *ssm.SSM {
 	return ssm.New(sess)
 }
 
-func ExportVariables(client *ssm.SSM, path string, recursive bool, nextToken string) {
-        input := &ssm.GetParametersByPathInput{
-                Path:           &path,
-                WithDecryption: aws.Bool(true),
-                Recursive: aws.Bool(recursive),
-        }
+func ExportVariables(client *ssm.SSM, path string, recursive bool, format string, nextToken string) {
+	input := &ssm.GetParametersByPathInput{
+		Path:           &path,
+		WithDecryption: aws.Bool(true),
+		Recursive:      aws.Bool(recursive),
+	}
 
 	if nextToken != "" {
 		input.SetNextToken(nextToken)
@@ -52,20 +63,25 @@ func ExportVariables(client *ssm.SSM, path string, recursive bool, nextToken str
 	}
 
 	for _, element := range output.Parameters {
-		PrintExportParameter(path, element)
+		OutputParameter(path, element, format)
 	}
 
 	if output.NextToken != nil {
-		ExportVariables(client, path, recursive, *output.NextToken)
+		ExportVariables(client, path, recursive, format, *output.NextToken)
 	}
 }
 
-func PrintExportParameter(path string, parameter *ssm.Parameter) {
+func OutputParameter(path string, parameter *ssm.Parameter, format string) {
 	name := *parameter.Name
 	value := *parameter.Value
 
 	env := strings.Replace(strings.Trim(name[len(path):], "/"), "/", "_", -1)
 	value = strings.Replace(value, "\n", "\\n", -1)
 
-	fmt.Printf("export %s=$'%s'\n", env, value)
+	switch format {
+	case formatExports:
+		fmt.Printf("export %s=$'%s'\n", env, value)
+	case formatDotenv:
+		fmt.Printf("%s=\"%s\"\n", env, value)
+	}
 }