Expand DRONE* variables before uploading the script

plugin.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"os"
 	"strconv"
 	"strings"
 	"sync"
@@ -86,6 +87,17 @@ func (p Plugin) Exec() error {
 				},
 			}
 
+			// expand DRONE env variables in script (like DRONE_DEPLOY_TO)
+			for index, _ := range p.Config.Script {
+				parts := strings.Split(p.Config.Script[index], " ")
+				for i, _ := range parts {
+					if strings.Contains(parts[i], "DRONE") {
+						parts[i] = os.ExpandEnv(parts[i])
+					}
+				}
+				p.Config.Script[index] = strings.Join(parts, " ")
+			}
+
 			p.log(host, "commands: ", strings.Join(p.Config.Script, "\n"))
 			stdoutChan, stderrChan, doneChan, errChan, err := ssh.Stream(strings.Join(p.Config.Script, "\n"), p.Config.CommandTimeout)
 			if err != nil {