From 6ecd65f0c983d619a656125342fb4448a359e0cd Mon Sep 17 00:00:00 2001
From: Patrick Connolly <patrick.c.connolly@gmail.com>
Date: Wed, 7 Nov 2018 22:24:35 +0800
Subject: [PATCH] Added ability to load remote configuration files. [#525]

---
 README.md               |  1 +
 bridge/api/api.go       | 38 ++++++++++++++++++++++++++++++++++++++
 bridge/bridge.go        |  4 ++++
 bridge/config/config.go |  9 +++++++++
 4 files changed, 52 insertions(+)

diff --git a/README.md b/README.md
index 1bcbf974..3f31f533 100644
--- a/README.md
+++ b/README.md
@@ -38,6 +38,7 @@ Minecraft server chat support via [MatterLink](https://github.com/elytra/MatterL
 * [Support multiple gateways(bridges) for your protocols](https://github.com/42wim/matterbridge/wiki/Features#support-multiple-gatewaysbridges-for-your-protocols)
 * [Message edits and deletes](https://github.com/42wim/matterbridge/wiki/Features#message-edits-and-deletes)
 * Preserves threading when possible
+* Remote configuration files
 * [Attachment / files handling](https://github.com/42wim/matterbridge/wiki/Features#attachment--files-handling)
 * [Username and avatar spoofing](https://github.com/42wim/matterbridge/wiki/Features#username-and-avatar-spoofing)
 * [Private groups](https://github.com/42wim/matterbridge/wiki/Features#private-groups)
diff --git a/bridge/api/api.go b/bridge/api/api.go
index eef41a4a..daffd074 100644
--- a/bridge/api/api.go
+++ b/bridge/api/api.go
@@ -2,7 +2,9 @@ package api
 
 import (
 	"encoding/json"
+	"io/ioutil"
 	"net/http"
+	"net/url"
 	"sync"
 	"time"
 
@@ -41,7 +43,9 @@ func New(cfg *bridge.Config) bridge.Bridger {
 			return key == b.GetString("Token"), nil
 		}))
 	}
+
 	e.GET("/api/health", b.handleHealthcheck)
+	e.PUT("/api/reload", b.handleConfigReload)
 	e.GET("/api/messages", b.handleMessages)
 	e.GET("/api/stream", b.handleStream)
 	e.POST("/api/message", b.handlePostMessage)
@@ -82,6 +86,40 @@ func (b *Api) handleHealthcheck(c echo.Context) error {
 	return c.String(http.StatusOK, "OK")
 }
 
+func (b *Api) handleConfigReload(c echo.Context) error {
+	cfgURL := b.GetString("ConfigURL")
+	if cfgURL == "" {
+		b.Log.Warning("Reload API triggered, but no config file url set.")
+		return c.String(http.StatusInternalServerError, "Internal Server Error")
+	}
+
+	b.Log.Debugf("Reloading config from remote file: " + cfgURL)
+	_, err := url.ParseRequestURI(cfgURL)
+	if err != nil {
+		b.Log.Error("Malformed config file url: ", err)
+		return c.String(http.StatusInternalServerError, "Internal Server Error")
+	}
+	res, err := http.Get(cfgURL)
+	defer res.Body.Close()
+	if err != nil {
+		b.Log.Error("Failed to fetch remote config file: ", err)
+		return c.String(http.StatusInternalServerError, "Internal Server Error")
+	}
+	content, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		b.Log.Error("Error reading remote config file: ", err)
+		return c.String(http.StatusInternalServerError, "Internal Server Error")
+	}
+	cfgfile := b.GetConfigFile()
+	err = ioutil.WriteFile(cfgfile, content, 0644)
+	if err != nil {
+		b.Log.Error("Failed to write remote config file: ", err)
+		return c.String(http.StatusInternalServerError, "Internal Server Error")
+	}
+
+	return c.String(http.StatusAccepted, "Accepted")
+}
+
 func (b *Api) handlePostMessage(c echo.Context) error {
 	message := config.Message{}
 	if err := c.Bind(&message); err != nil {
diff --git a/bridge/bridge.go b/bridge/bridge.go
index 0436eeb6..25e448fe 100644
--- a/bridge/bridge.go
+++ b/bridge/bridge.go
@@ -68,6 +68,10 @@ func (b *Bridge) joinChannels(channels map[string]config.ChannelInfo, exists map
 	return nil
 }
 
+func (b *Bridge) GetConfigFile() string {
+	return b.Config.GetConfigFile()
+}
+
 func (b *Bridge) GetBool(key string) bool {
 	if b.Config.GetBool(b.Account + "." + key) {
 		return b.Config.GetBool(b.Account + "." + key)
diff --git a/bridge/config/config.go b/bridge/config/config.go
index bdf77f88..ea64809a 100644
--- a/bridge/config/config.go
+++ b/bridge/config/config.go
@@ -66,6 +66,7 @@ type Protocol struct {
 	Buffer                 int    // api
 	Charset                string // irc
 	ColorNicks             bool   // only irc for now
+	ConfigURL              string // api
 	Debug                  bool   // general
 	DebugLevel             int    // only for irc now
 	EditSuffix             string // mattermost, slack, discord, telegram, gitter
@@ -172,6 +173,7 @@ type ConfigValues struct {
 	General            Protocol
 	Gateway            []Gateway
 	SameChannelGateway []SameChannelGateway
+	ConfigFile         string
 }
 
 type Config struct {
@@ -196,6 +198,9 @@ func NewConfig(cfgfile string) *Config {
 	viper.OnConfigChange(func(e fsnotify.Event) {
 		flog.Println("Config file changed:", e.Name)
 	})
+
+	mycfg.v.Set("ConfigFile", cfgfile)
+	mycfg.ConfigValues = &cfg
 	return mycfg
 }
 
@@ -229,6 +234,10 @@ func NewConfigFromString(input []byte) *Config {
 	return mycfg
 }
 
+func (c *Config) GetConfigFile() string {
+	return c.v.GetString("ConfigFile")
+}
+
 func (c *Config) GetBool(key string) bool {
 	c.RLock()
 	defer c.RUnlock()