Add /kills command with save state functionality (#4)

* Add /kills command with save state functionality

CHANGELOG:

- Kills state it's loaded at session start, if doesn't exists set to 0.
- Kills state it's saved on the file kills.txt
- Kills state it's saved after each ban, to ensure being saved.
- If /kills it's called will report the current kills state.

* Add unit tests

* Improve test coverage on edge cases: fix some behaviors too

Important fix: os.O_TRUNC should be set as flag in os.OpenFile to
overwrite the kills.txt file properly.

Otherwise, ff the kills.txt had initially "random-fuckups", writing 10
will turn out in: "10ndom-fuckups".

This is not the intended behavior.

* Separate main function in main.go and mark as !test

This will make more easier to control the unit tests, since main is
not possible to test.

.github/workflows/test.yml

@@ -47,7 +47,7 @@ jobs:
     - name: Calc coverage
       run: |
         export PATH=$PATH:$(go env GOPATH)/bin
-        go test -v -covermode=count -coverprofile=coverage.out
+        go test -v -covermode=count -tags test -coverprofile=coverage.out
     - name: Convert coverage to lcov
       uses: jandelgado/gcov2lcov-action@v1.0.0
       with:

.gitignore

@@ -17,3 +17,4 @@
 /troll-shield
 
 *.log
+/kills.txt

main.go

@@ -0,0 +1,63 @@
+//+build !test
+// Copyright 2020 the commonlispbr authors. All rights reserved
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"strings"
+)
+
+func main() {
+	setupLogging()
+	bot, botHidden, err := setupBots()
+	if err != nil {
+		log.Fatal(err.Error())
+	}
+	kills := loadKills(killsFile)
+	log.Printf("Currently kill state: %v", kills)
+
+	for update := range getUpdates(bot) {
+		if messageEvent(&update) {
+			if update.Message.Text == "/lelerax" {
+				reply(bot, &update, "Estou vivo.")
+			}
+
+			if update.Message.Text == "/kills" {
+				reportKills(bot, &update, kills)
+			}
+
+			// Exit automatically from group after the bot receive a message from it
+			for _, trollGroup := range trollGroups {
+				if fromChatEvent(&update, strings.TrimLeft(trollGroup, "@")) {
+					leaveChat(bot, &update, trollGroup)
+				}
+			}
+		}
+
+		if newChatMemberEvent(&update) {
+			for _, member := range *update.Message.NewChatMembers {
+				if trollHouse := findTrollHouses(botHidden, member.ID); trollHouse != "" {
+					err := kickTroll(bot, &update, member, trollHouse)
+					if err == nil {
+						kills++
+						if err := saveKills(killsFile, kills); err != nil {
+							log.Printf("saving kills failed: %v", err)
+						}
+					}
+				} else if fromChatEvent(&update, "commonlispbr") && !member.IsBot {
+					welcomeMessage(bot, &update, member)
+				}
+
+				// Exit automatically from groups when I'm joining it
+				for _, trollGroup := range trollGroups {
+					if fromChatEvent(&update, strings.TrimLeft(trollGroup, "@")) && member.UserName == bot.Self.UserName {
+						leaveChat(bot, &update, trollGroup)
+					}
+				}
+
+			}
+		}
+	}
+}

troll_shield.go

@@ -7,8 +7,10 @@ package main
 import (
 	"fmt"
 	"io"
+	"io/ioutil"
 	logger "log"
 	"os"
+	"strconv"
 	"strings"
 	"sync"
 
@@ -38,6 +40,7 @@ var trollGroups = []string{
 }
 
 const logfile = "troll-shield.log"
+const killsFile = "kills.txt"
 
 var log = logger.New(os.Stderr, "", logger.LstdFlags)
 
@@ -139,7 +142,7 @@ func findTrollHouses(bot TrollShieldBot, userID int) string {
 }
 
 // kickTroll ban the troll and send a message about where we can found the trolls
-func kickTroll(bot TrollShieldBot, update *telegram.Update, user telegram.User, trollHouse string) {
+func kickTroll(bot TrollShieldBot, update *telegram.Update, user telegram.User, trollHouse string) error {
 	chatMember := telegram.ChatMemberConfig{
 		ChatID: update.Message.Chat.ID,
 		UserID: user.ID,
@@ -161,6 +164,8 @@ func kickTroll(bot TrollShieldBot, update *telegram.Update, user telegram.User,
 		)
 		reply(bot, update, text)
 	}
+
+	return err
 }
 
 func setupLogging() {
@@ -229,43 +234,35 @@ func leaveChat(bot TrollShieldBot, update *telegram.Update, trollGroup string) {
 	}
 }
 
-func main() {
-	setupLogging()
-	bot, botHidden, err := setupBots()
-	if err != nil {
-		log.Fatal(err.Error())
+func loadKills(fpath string) int64 {
+	dat, err := ioutil.ReadFile(fpath)
+	if err == nil {
+		i, err := strconv.Atoi(strings.TrimSpace(string(dat)))
+		if err != nil {
+			log.Printf("Parsing %q go bad, got error: %v", fpath, err)
+		} else {
+			return int64(i)
+		}
 	}
 
-	for update := range getUpdates(bot) {
-		if messageEvent(&update) {
-			if update.Message.Text == "/lelerax" {
-				reply(bot, &update, "Estou vivo.")
-			}
-
-			// Exit automatically from group after the bot receive a message from it
-			for _, trollGroup := range trollGroups {
-				if fromChatEvent(&update, strings.TrimLeft(trollGroup, "@")) {
-					leaveChat(bot, &update, trollGroup)
-				}
-			}
-		}
+	return 0
+}
 
-		if newChatMemberEvent(&update) {
-			for _, member := range *update.Message.NewChatMembers {
-				if trollHouse := findTrollHouses(botHidden, member.ID); trollHouse != "" {
-					kickTroll(bot, &update, member, trollHouse)
-				} else if fromChatEvent(&update, "commonlispbr") && !member.IsBot {
-					welcomeMessage(bot, &update, member)
-				}
-
-				// Exit automatically from groups when I'm joining it
-				for _, trollGroup := range trollGroups {
-					if fromChatEvent(&update, strings.TrimLeft(trollGroup, "@")) && member.UserName == bot.Self.UserName {
-						leaveChat(bot, &update, trollGroup)
-					}
-				}
+func saveKills(fpath string, kills int64) error {
+	f, err := os.OpenFile(fpath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)
+	if err == nil {
+		_, err = f.WriteString(strconv.FormatInt(kills, 10))
+	}
+	if e := f.Close(); e != nil {
+		err = e
+	}
+	return err
+}
 
-			}
-		}
+func reportKills(bot TrollShieldBot, update *telegram.Update, kills int64) {
+	txt := fmt.Sprintf("%v foram sacrificados.", kills)
+	if kills%2 == 0 {
+		txt = fmt.Sprintf("Já taquei o pau em %v trolls!", kills)
 	}
+	reply(bot, update, txt)
 }

troll_shield_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"errors"
+	"io/ioutil"
 	"os"
 	"testing"
 
@@ -142,9 +143,13 @@ func TestKickTroll(t *testing.T) {
 	message.Chat = &chat
 	update.Message = &message
 	user := telegram.User{}
-	kickTroll(&botnilson, &update, user, "@trollhouse")
+	if err := kickTroll(&botnilson, &update, user, "@trollhouse"); err != nil {
+		t.Errorf("kickTroll error: %v", err)
+	}
 	user.ID = 1
-	kickTroll(&botnilson, &update, user, "@trollhouse")
+	if err := kickTroll(&botnilson, &update, user, "@trollhouse"); err == nil {
+		t.Errorf("kickTroll should fail, but got: %v", err)
+	}
 }
 
 func TestWelcomeMessage(t *testing.T) {
@@ -202,3 +207,48 @@ func TestGetUpdates(t *testing.T) {
 	bot := BotMockup{}
 	getUpdates(&bot)
 }
+
+func TestSaveLoadKills(t *testing.T) {
+	tmpfile, err := ioutil.TempFile("", "kills.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	content := []byte("isso-nao-eh-um-numero")
+	if _, err := tmpfile.Write(content); err != nil {
+		t.Fatal(err)
+	}
+
+	if kills := loadKills(tmpfile.Name()); kills != 0 {
+		t.Errorf("loadKills should return 0 when there is a invalid number, got: %v", kills)
+	}
+
+	// write 10
+	if err := saveKills(tmpfile.Name(), 10); err != nil {
+		t.Errorf("saveKills failed: %v", err)
+	}
+
+	// read 10
+	if kills := loadKills(tmpfile.Name()); kills != 10 {
+		t.Errorf("Save/Load of KillCounter didn't worked, expected 10, got %v", kills)
+	}
+
+	if err := tmpfile.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := os.Remove(tmpfile.Name()); err != nil {
+		t.Fatal(err)
+	}
+
+}
+
+func TestReportKills(t *testing.T) {
+	bot := BotMockup{}
+	update := telegram.Update{}
+	message := telegram.Message{}
+	chat := telegram.Chat{}
+	message.Chat = &chat
+	update.Message = &message
+	reportKills(&bot, &update, int64(11))
+	reportKills(&bot, &update, int64(10))
+}