From 3e44a44f5040981341e11b53d71283b95e2004d2 Mon Sep 17 00:00:00 2001
From: Aaron Bieber <aaron@bolddaemon.com>
Date: Tue, 18 Feb 2020 20:20:01 -0700
Subject: [PATCH] add ability to check federation status of homeservers

---
 README.md             |   1 +
 plugins/federation.go | 110 ++++++++++++++++++++++++++++++++++++++++++
 plugins/plugins.go    |   1 +
 3 files changed, 112 insertions(+)
 create mode 100644 plugins/federation.go

diff --git a/README.md b/README.md
index 86cb956..7007d0d 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,7 @@
 |Beat|`(?i)^\.beat$|^what time is it\?$|^beat( )?time:?\??$`|Print the current [beat time](https://en.wikipedia.org/wiki/Swatch_Internet_Time).|
 |Beer|`(?i)^beer: `|Queries [OpenDataSoft](https://public-us.opendatasoft.com/explore/dataset/open-beer-database/table/)'s beer database for a given beer.|
 |BotSnack|`(?i)botsnack`|Consumes a botsnack. This pleases mcchunkie and brings balance to the universe.|
+|Feder|`(?i)^feder: (.*)$`|check the Matrix federation status of a given URL.|
 |HighFive|`o/|\o`|Everyone loves highfives.|
 |Hi|`(?i)^hi|hi$`|Friendly bots say hi.|
 |LoveYou|`(?i)i love you`|Spreading love where ever we can by responding when someone shows us love.|
diff --git a/plugins/federation.go b/plugins/federation.go
new file mode 100644
index 0000000..cb26fc3
--- /dev/null
+++ b/plugins/federation.go
@@ -0,0 +1,110 @@
+package plugins
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"net/url"
+	"regexp"
+
+	"github.com/matrix-org/gomatrix"
+)
+
+// ServiceInfo represents the version info from a response
+type ServiceInfo struct {
+	Name    string `json:"name"`
+	Version string `json:"version"`
+}
+
+// FedResp represents a federation statuse response
+type FedResp struct {
+	Status bool        `json:"FederationOK"`
+	Info   ServiceInfo `json:"Version"`
+}
+
+// Feder responds to federation check requests
+type Feder struct {
+}
+
+// Descr describes this plugin
+func (h *Feder) Descr() string {
+	return "check the Matrix federation status of a given URL."
+}
+
+// Re returns the federation check matching string
+func (h *Feder) Re() string {
+	return `(?i)^feder: (.*)$`
+}
+
+func (h *Feder) fix(msg string) string {
+	re := regexp.MustCompile(h.Re())
+	return re.ReplaceAllString(msg, "$1")
+}
+
+// Match determines if we should call the response for Feder
+func (h *Feder) Match(user, msg string) bool {
+	re := regexp.MustCompile(h.Re())
+	return re.MatchString(msg)
+}
+
+func (h *Feder) get(hserver string) (*FedResp, error) {
+	u := "https://federationtester.matrix.org/api/report?server_name="
+	u = fmt.Sprintf("%s%s", u, url.PathEscape(hserver))
+	resp, err := http.Get(u)
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var fresp = &FedResp{}
+	err = json.Unmarshal([]byte(body), fresp)
+	if err != nil {
+		return nil, err
+	}
+
+	return fresp, nil
+}
+
+// SetStore we don't need a store here.
+func (h *Feder) SetStore(s PluginStore) {}
+
+// RespondText to looking up of federation check requests
+func (h *Feder) RespondText(c *gomatrix.Client, ev *gomatrix.Event, user, post string) {
+	homeServer := h.fix(post)
+	if homeServer != "" {
+		u, err := url.Parse(fmt.Sprintf("https://%s", homeServer))
+		if err != nil {
+			SendText(c, ev.RoomID, "that's not a real host name.")
+			return
+		}
+
+		homeServer = u.Hostname()
+
+		log.Printf("%s: responding to '%s'", h.Name(), ev.Sender)
+		fed, err := h.get(homeServer)
+		if err != nil {
+			SendText(c, ev.RoomID, fmt.Sprintf("sorry %s, I can't look up the federation status (%s)", ev.Sender, err))
+		}
+
+		stat := "broken"
+		if fed.Status {
+			stat = "OK"
+		}
+		SendText(c, ev.RoomID, fmt.Sprintf("%s is running %s (%s) and is %s.",
+			homeServer, fed.Info.Name, fed.Info.Version, stat))
+
+	}
+}
+
+// Name Feder!
+func (h *Feder) Name() string {
+	return "Feder"
+}
diff --git a/plugins/plugins.go b/plugins/plugins.go
index b84832c..f9b8dba 100644
--- a/plugins/plugins.go
+++ b/plugins/plugins.go
@@ -73,6 +73,7 @@ var Plugs = Plugins{
 	&Beat{},
 	&Beer{},
 	&BotSnack{},
+	&Feder{},
 	&HighFive{},
 	&Hi{},
 	&LoveYou{},