Set exit-code when non-zero

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Author: alexellis

.gitignore

@@ -1 +1,2 @@
 /go-execute
+main.go

README.md

@@ -8,31 +8,54 @@ A simple wrapper for Go's command execution packages.
 
 See Godoc [github.com/alexellis/go-execute](https://godoc.org/github.com/alexellis/go-execute)
 
-## Example
+## Example with "shell" and exit-code 0
 
 ```golang
 package main
 
 import (
 	"fmt"
-	"os"
 
 	execute "github.com/alexellis/go-execute/pkg/v1"
 )
 
 func main() {
 	ls := execute.ExecTask{
 		Command: "ls",
-		Args:    []string{"-la"},
-		Cwd:     os.Getenv("HOME"),
+		Args:    []string{"-l"},
 		Shell:   true,
 	}
 	res, err := ls.Execute()
 	if err != nil {
 		panic(err)
 	}
 
-	fmt.Println(res.Stdout, res.Stderr)
+	fmt.Printf("stdout: %q, stderr: %q, exit-code: %d\n", res.Stdout, res.Stderr, res.ExitCode)
+}
+```
+
+## Example with "shell" and exit-code 1
+
+```golang
+package main
+
+import (
+	"fmt"
+
+	execute "github.com/alexellis/go-execute/pkg/v1"
+)
+
+func main() {
+	ls := execute.ExecTask{
+		Command: "exit 1",
+		Shell:   true,
+	}
+	res, err := ls.Execute()
+	if err != nil {
+		panic(err)
+	}
+
+	fmt.Printf("stdout: %q, stderr: %q, exit-code: %d\n", res.Stdout, res.Stderr, res.ExitCode)
 }
 ```
 

pkg/v1/exec.go

@@ -42,8 +42,9 @@ func (et ExecTask) Execute() (ExecResult, error) {
 		} else {
 			script := strings.Join(et.Args, " ")
 			args = append([]string{"-c"}, fmt.Sprintf("%s %s", et.Command, script))
+
 		}
-		fmt.Println(args)
+
 		cmd = exec.Command("/bin/bash", args...)
 	} else {
 		if strings.Index(et.Command, " ") > 0 {
@@ -95,8 +96,18 @@ func (et ExecTask) Execute() (ExecResult, error) {
 
 	fmt.Println("res: " + string(stdoutBytes))
 
+	exitCode := 0
+	execErr := cmd.Wait()
+	if execErr != nil {
+		if exitError, ok := execErr.(*exec.ExitError); ok {
+
+			exitCode = exitError.ExitCode()
+		}
+	}
+
 	return ExecResult{
-		Stdout: string(stdoutBytes),
-		Stderr: string(stderrBytes),
+		Stdout:   string(stdoutBytes),
+		Stderr:   string(stderrBytes),
+		ExitCode: exitCode,
 	}, nil
 }