fix docker home path on windows

Added docker configuration

cmd/drone-docker/main.go

@@ -7,7 +7,7 @@ import (
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli"
 
-	"github.com/drone-plugins/drone-docker"
+	docker "github.com/drone-plugins/drone-docker"
 )
 
 var (
@@ -208,6 +208,11 @@ func main() {
 			Usage:  "docker email",
 			EnvVar: "PLUGIN_EMAIL,DOCKER_EMAIL",
 		},
+		cli.StringFlag{
+			Name:   "docker.config",
+			Usage:  "docker json dockerconfig content",
+			EnvVar: "PLUGIN_CONFIG",
+		},
 		cli.BoolTFlag{
 			Name:   "docker.purge",
 			Usage:  "docker should cleanup images",
@@ -244,6 +249,7 @@ func run(c *cli.Context) error {
 			Username: c.String("docker.username"),
 			Password: c.String("docker.password"),
 			Email:    c.String("docker.email"),
+			Config:   c.String("docker.config"),
 		},
 		Build: docker.Build{
 			Remote:      c.String("remote.url"),

daemon.go

@@ -9,6 +9,7 @@ import (
 
 const dockerExe = "/usr/local/bin/docker"
 const dockerdExe = "/usr/local/bin/dockerd"
+const dockerHome = "/root/.docker/"
 
 func (p Plugin) startDaemon() {
 	cmd := commandDaemon(p.Daemon)
@@ -23,4 +24,4 @@ func (p Plugin) startDaemon() {
 		trace(cmd)
 		cmd.Run()
 	}()
-}
+}

daemon_win.go

@@ -4,6 +4,7 @@ package docker
 
 const dockerExe = "C:\\bin\\docker.exe"
 const dockerdExe = ""
+const dockerHome = "C:\\ProgramData\\docker\\"
 
 func (p Plugin) startDaemon() {
 	// this is a no-op on windows

docker.go

@@ -2,8 +2,10 @@ package docker
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 	"time"
 )
@@ -32,6 +34,7 @@ type (
 		Username string // Docker registry username
 		Password string // Docker registry password
 		Email    string // Docker registry email
+		Config   string // Docker Auth Config
 	}
 
 	// Build defines Docker build parameters.
@@ -83,6 +86,17 @@ func (p Plugin) Exec() error {
 		time.Sleep(time.Second * 1)
 	}
 
+	// Create Auth Config File
+	if p.Login.Config != "" {
+		os.MkdirAll(dockerHome, 0600)
+
+		path := filepath.Join(dockerHome, "config.json")
+		err := ioutil.WriteFile(path, []byte(p.Login.Config), 0600)
+		if err != nil {
+			return fmt.Errorf("Error writeing config.json: %s", err)
+		}
+	}
+
 	// login to the Docker registry
 	if p.Login.Password != "" {
 		cmd := commandLogin(p.Login)
@@ -90,8 +104,15 @@ func (p Plugin) Exec() error {
 		if err != nil {
 			return fmt.Errorf("Error authenticating: %s", err)
 		}
-	} else {
-		fmt.Println("Registry credentials not provided. Guest mode enabled.")
+	}
+
+	switch {
+	case p.Login.Password != "":
+		fmt.Println("Detected registry credentials")
+	case p.Login.Config != "":
+		fmt.Println("Detected registry credentials file")
+	default:
+		fmt.Println("Registry credentials or Docker config not provided. Guest mode enabled.")
 	}
 
 	if p.Build.Squash && !p.Daemon.Experimental {