From 9429c843c854c0a8d9f9e5710dd6903afabeefb3 Mon Sep 17 00:00:00 2001
From: Matthew Holt <mholt@users.noreply.github.com>
Date: Fri, 5 Jul 2019 09:59:13 -0600
Subject: [PATCH] cmd: New reload command

---
 admin.go        |  6 +++++-
 cmd/commands.go | 57 +++++++++++++++++++++++++++++++++++++++++++++++++
 cmd/main.go     |  3 ++-
 3 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/admin.go b/admin.go
index 11be4f23..f3337b0c 100644
--- a/admin.go
+++ b/admin.go
@@ -44,7 +44,7 @@ type AdminConfig struct {
 // DefaultAdminConfig is the default configuration
 // for the administration endpoint.
 var DefaultAdminConfig = &AdminConfig{
-	Listen: "localhost:2019",
+	Listen: DefaultAdminListen,
 }
 
 // StartAdmin starts Caddy's administration endpoint,
@@ -192,6 +192,10 @@ func Load(r io.Reader) error {
 	return nil
 }
 
+// DefaultAdminListen is the address for the admin
+// listener, if none is specified at startup.
+var DefaultAdminListen = "localhost:2019"
+
 var bufPool = sync.Pool{
 	New: func() interface{} {
 		return new(bytes.Buffer)
diff --git a/cmd/commands.go b/cmd/commands.go
index f98b4019..5e0217a8 100644
--- a/cmd/commands.go
+++ b/cmd/commands.go
@@ -15,12 +15,16 @@
 package caddycmd
 
 import (
+	"bytes"
 	"crypto/rand"
+	"encoding/json"
 	"flag"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"log"
 	"net"
+	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -200,6 +204,59 @@ func cmdStop() (int, error) {
 	return 0, nil
 }
 
+func cmdReload() (int, error) {
+	reloadCmd := flag.NewFlagSet("load", flag.ExitOnError)
+	reloadCmdConfigFlag := reloadCmd.String("config", "", "Configuration file")
+	reloadCmdAddrFlag := reloadCmd.String("address", "", "Address of the administration listener, if different from config")
+	reloadCmd.Parse(os.Args[2:])
+
+	// a configuration is required
+	if *reloadCmdConfigFlag == "" {
+		return 1, fmt.Errorf("no configuration to load (use --config)")
+	}
+
+	// load the configuration file
+	config, err := ioutil.ReadFile(*reloadCmdConfigFlag)
+	if err != nil {
+		return 1, fmt.Errorf("reading config file: %v", err)
+	}
+
+	// get the address of the admin listener and craft endpoint URL
+	adminAddr := *reloadCmdAddrFlag
+	if adminAddr == "" {
+		var tmpStruct struct {
+			Admin caddy.AdminConfig `json:"admin"`
+		}
+		err = json.Unmarshal(config, &tmpStruct)
+		if err != nil {
+			return 1, fmt.Errorf("unmarshaling admin listener address from config: %v", err)
+		}
+		adminAddr = tmpStruct.Admin.Listen
+	}
+	if adminAddr == "" {
+		adminAddr = caddy.DefaultAdminListen
+	}
+	adminEndpoint := fmt.Sprintf("http://%s/load", adminAddr)
+
+	// send the configuration to the instance
+	resp, err := http.Post(adminEndpoint, "application/json", bytes.NewReader(config))
+	if err != nil {
+		return 1, fmt.Errorf("sending configuration to instance: %v", err)
+	}
+	defer resp.Body.Close()
+
+	// if it didn't work, let the user know
+	if resp.StatusCode >= 400 {
+		respBody, err := ioutil.ReadAll(io.LimitReader(resp.Body, 1024*10))
+		if err != nil {
+			return 1, fmt.Errorf("HTTP %d: reading error message: %v", resp.StatusCode, err)
+		}
+		return 1, fmt.Errorf("caddy responded with error: HTTP %d: %s", resp.StatusCode, respBody)
+	}
+
+	return 0, nil
+}
+
 func cmdVersion() (int, error) {
 	goModule := caddy.GoModule()
 	if goModule.Sum != "" {
diff --git a/cmd/main.go b/cmd/main.go
index 217bd743..4691b37a 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -51,8 +51,9 @@ type commandFunc func() (int, error)
 
 var commands = map[string]commandFunc{
 	"start":        cmdStart,
-	"stop":         cmdStop,
 	"run":          cmdRun,
+	"stop":         cmdStop,
+	"reload":       cmdReload,
 	"version":      cmdVersion,
 	"list-modules": cmdListModules,
 	"environ":      cmdEnviron,