ability to inject private params into the drone build cli command

cli/build.go

@@ -78,13 +78,21 @@ func buildCommandFunc(c *cli.Context) {
 func run(path, identity string, privileged bool) (int, error) {
 	dockerClient := docker.New()
 
+	// parse the private environment variables
+	envs := getParamMap("DRONE_ENV_")
+
 	// parse the Drone yml file
-	s, err := script.ParseBuildFile(path)
+	s, err := script.ParseBuildFile(script.Inject(path, envs))
 	if err != nil {
 		log.Err(err.Error())
 		return EXIT_STATUS, err
 	}
 
+	// inject private environment variables into build script
+	for key, val := range envs {
+		s.Env = append(s.Env, key+"="+val)
+	}
+
 	// remove deploy & publish sections
 	// for now, until I fix bug
 	s.Publish = nil

cli/util.go

@@ -67,13 +67,24 @@ func getRepoPath(dir string) (path string, ok bool) {
 	return dir[index+5:], true
 }
 
-// getGitOrigin checks the .git origin in an attempt
-// to correctly determine the code's package path. This
-// is Go-specific, since Go code must exist in
-// $GOPATH/src/github.com/{owner}/{name}
-func getGitOrigin(dir string) (path string, ok bool) {
-	// TODO
-	return
+// GetRepoMap returns a map of enivronment variables that
+// should be injected into the .drone.yml
+func getParamMap(prefix string) map[string]string {
+	envs := map[string]string{}
+
+	for _, item := range os.Environ() {
+		env := strings.SplitN(item, "=", 2)
+		if len(env) != 2 {
+			continue
+		}
+
+		key := env[0]
+		val := env[1]
+		if strings.HasPrefix(key, prefix) {
+			envs[strings.TrimPrefix(key, prefix)] = val
+		}
+	}
+	return envs
 }
 
 // prints the time as a human readable string