cmd: add ability to read config from stdin (#3898)

1 files changed, 5 insertions, 1 deletions

diff --git a/cmd/main.go b/cmd/main.go
index e92e71f..2dfb867 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -123,7 +123,11 @@ func loadConfig(configFile, adapterName string) ([]byte, string, error) {
 	var cfgAdapter caddyconfig.Adapter
 	var err error
 	if configFile != "" {
-		config, err = ioutil.ReadFile(configFile)
+		if configFile == "-" {
+			config, err = ioutil.ReadAll(os.Stdin)
+		} else {
+			config, err = ioutil.ReadFile(configFile)
+		}
 		if err != nil {
 			return nil, "", fmt.Errorf("reading config file: %v", err)
 		}