feat: postgres database integration

.env.example

@@ -1 +1,14 @@
+ENV="staging"
 BOT_TOKEN="your-bot-token"
+DATABASE_URL= #"postgres://pen_bot:pen_bot_password@postgres:5432/pen_bot?sslmode=disable"
+DB_NAME="pen_bot"
+DB_HOST="localhost"
+DB_PORT="5432"
+DB_USER="pen_bot"
+DB_PASSWORD="pen_bot_password"
+DB_BOT_INSTANCE_ID="pen-bot-1"
+DB_MAX_OPEN_CONNS="16"
+DB_MAX_IDLE_CONNS="4"
+DB_CONN_MAX_LIFETIME="30m"
+DB_CACHE_CLEANUP_INTERVAL="15m"
+POSTGRES_PASSWORD="pen_bot_password"

docker-compose.yml

@@ -4,7 +4,27 @@ services:
     pull_policy: build
     env_file:
       - .env
+    depends_on:
+      postgres:
+        condition: service_healthy
     develop:
       watch:
         - action: rebuild
           path: .
+
+  postgres:
+    image: postgres:16-alpine
+    environment:
+      POSTGRES_DB: pen_bot
+      POSTGRES_USER: pen_bot
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-pen_bot_password}
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U $${POSTGRES_USER}"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+volumes:
+  postgres_data:

go.mod

@@ -4,6 +4,8 @@ go 1.26.2
 
 require github.com/disgoorg/disgo v0.19.3
 
+require github.com/lib/pq v1.12.3
+
 require (
 	github.com/disgoorg/godave v0.1.0 // indirect
 	github.com/disgoorg/json/v2 v2.0.0 // indirect

go.sum

@@ -14,6 +14,8 @@ github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aN
 github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/klauspost/compress v1.18.4 h1:RPhnKRAQ4Fh8zU2FY/6ZFDwTVTxgJ/EMydqSTzE9a2c=
 github.com/klauspost/compress v1.18.4/go.mod h1:R0h/fSBs8DE4ENlcrlib3PsXS61voFxhIs2DeRhCvJ4=
+github.com/lib/pq v1.12.3 h1:tTWxr2YLKwIvK90ZXEw8GP7UFHtcbTtty8zsI+YjrfQ=
+github.com/lib/pq v1.12.3/go.mod h1:/p+8NSbOcwzAEI7wiMXFlgydTwcgTr3OSKMsD2BitpA=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sasha-s/go-csync v0.0.0-20240107134140-fcbab37b09ad h1:qIQkSlF5vAUHxEmTbaqt1hkJ/t6skqEGYiMag343ucI=

internal/core/start.go

@@ -8,7 +8,9 @@ import (
 	"strings"
 	"sync"
 	"syscall"
+	"time"
 
+	"github.com/Neon-Genesis-Linux/pen-bot/internal/db"
 	"github.com/disgoorg/disgo"
 	"github.com/disgoorg/disgo/bot"
 	"github.com/disgoorg/disgo/events"
@@ -78,10 +80,68 @@ func Start(ctx context.Context, token string, listener func(*events.MessageCreat
 		return err
 	}
 
+	cleanupCtx, cleanupCancel := context.WithCancel(context.Background())
+	defer cleanupCancel()
+	cleanupInterval := db.ParseCleanupIntervalEnv("DB_CACHE_CLEANUP_INTERVAL", 15)
+	go func() {
+		defer func() {
+			if r := recover(); r != nil {
+				slog.Error("cache cleanup panicked", "recover", r)
+			}
+		}()
+		db.StartCleanup(cleanupCtx, cleanupInterval)
+	}()
+
+	go func() {
+		defer func() {
+			if r := recover(); r != nil {
+				slog.Error("db connect panicked", "recover", r)
+			}
+		}()
+		connectDBWithRetry(ctx)
+	}()
+
+	defer db.CloseDB()
+
 	slog.Info("pen bot is now running. Press CTRL-C to exit.")
 	s := make(chan os.Signal, 1)
 	signal.Notify(s, syscall.SIGINT, syscall.SIGTERM, os.Interrupt)
-	<-s
 
-	return nil
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-s:
+		return nil
+	}
+}
+
+func connectDBWithRetry(ctx context.Context) {
+	var dbClient *db.DB
+	var err error
+
+	for attempt := range 10 {
+		dbClient, err = db.NewFromEnv()
+		if err == nil {
+			break
+		}
+		slog.Warn("db connection attempt failed", "attempt", attempt+1, "error", err)
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(time.Duration(attempt+1) * 2 * time.Second):
+		}
+	}
+	if err != nil {
+		slog.Error("db unavailable after retries", "error", err)
+		return
+	}
+
+	if err := db.ApplyMigrations(ctx, dbClient); err != nil {
+		slog.Error("db migration failed", "error", err)
+		_ = dbClient.Close()
+		return
+	}
+
+	db.SetGlobalDB(dbClient)
+	slog.Info("db connected and ready")
 }

internal/core/start_test.go

@@ -0,0 +1,99 @@
+package core
+
+import (
+	"testing"
+
+	"github.com/disgoorg/disgo/discord"
+	"github.com/disgoorg/disgo/events"
+)
+
+func TestDispatchExactMatch(t *testing.T) {
+	called := false
+	RegisterCommand("test-exact", func(e *events.MessageCreate) { called = true })
+	defer delete(commandRegistry, "test-exact")
+
+	DispatchCommand(&events.MessageCreate{
+		GenericMessage: &events.GenericMessage{
+			Message: discord.Message{
+				Content: "!test-exact",
+				Author:  discord.User{Bot: false},
+			},
+		},
+	})
+
+	if !called {
+		t.Fatal("expected handler called")
+	}
+}
+
+func TestDispatchIgnoresBot(t *testing.T) {
+	called := false
+	RegisterCommand("test-bot", func(e *events.MessageCreate) { called = true })
+	defer delete(commandRegistry, "test-bot")
+
+	DispatchCommand(&events.MessageCreate{
+		GenericMessage: &events.GenericMessage{
+			Message: discord.Message{
+				Content: "!test-bot",
+				Author:  discord.User{Bot: true},
+			},
+		},
+	})
+
+	if called {
+		t.Fatal("expected bot message ignored")
+	}
+}
+
+func TestDispatchNoPrefix(t *testing.T) {
+	called := false
+	RegisterCommand("test-noprefix", func(e *events.MessageCreate) { called = true })
+	defer delete(commandRegistry, "test-noprefix")
+
+	DispatchCommand(&events.MessageCreate{
+		GenericMessage: &events.GenericMessage{
+			Message: discord.Message{
+				Content: "test-noprefix",
+				Author:  discord.User{Bot: false},
+			},
+		},
+	})
+
+	if called {
+		t.Fatal("expected no dispatch without prefix")
+	}
+}
+
+func TestDispatchUnknownCommand(t *testing.T) {
+	DispatchCommand(&events.MessageCreate{
+		GenericMessage: &events.GenericMessage{
+			Message: discord.Message{
+				Content: "!unknown-cmd",
+				Author:  discord.User{Bot: false},
+			},
+		},
+	})
+}
+
+func TestCustomPrefix(t *testing.T) {
+	oldPrefix := botPrefix
+	botPrefix = "?"
+	t.Cleanup(func() { botPrefix = oldPrefix })
+
+	called := false
+	RegisterCommand("test-custom", func(e *events.MessageCreate) { called = true })
+	defer delete(commandRegistry, "test-custom")
+
+	DispatchCommand(&events.MessageCreate{
+		GenericMessage: &events.GenericMessage{
+			Message: discord.Message{
+				Content: "?test-custom",
+				Author:  discord.User{Bot: false},
+			},
+		},
+	})
+
+	if !called {
+		t.Fatal("expected handler called with custom prefix")
+	}
+}

internal/db/cache.go

@@ -0,0 +1,70 @@
+package db
+
+import (
+	"context"
+	"sync"
+	"time"
+)
+
+type memCacheEntry struct {
+	data      []byte
+	expiresAt time.Time
+}
+
+var (
+	mc   = make(map[string]memCacheEntry)
+	mcMu sync.RWMutex
+)
+
+func SetCacheEntry(key string, valueJSON []byte, ttl time.Duration) {
+	mcMu.Lock()
+	defer mcMu.Unlock()
+	var expiresAt time.Time
+	if ttl > 0 {
+		expiresAt = time.Now().Add(ttl)
+	}
+	mc[key] = memCacheEntry{data: valueJSON, expiresAt: expiresAt}
+}
+
+func GetCacheEntry(key string) ([]byte, bool) {
+	mcMu.RLock()
+	e, ok := mc[key]
+	mcMu.RUnlock()
+	if !ok {
+		return nil, false
+	}
+	if !e.expiresAt.IsZero() && time.Now().After(e.expiresAt) {
+		mcMu.Lock()
+		delete(mc, key)
+		mcMu.Unlock()
+		return nil, false
+	}
+	return e.data, true
+}
+
+func DeleteCacheEntry(key string) {
+	mcMu.Lock()
+	defer mcMu.Unlock()
+	delete(mc, key)
+}
+
+func StartCleanup(ctx context.Context, interval time.Duration) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			mcMu.Lock()
+			now := time.Now()
+			for k, e := range mc {
+				if !e.expiresAt.IsZero() && now.After(e.expiresAt) {
+					delete(mc, k)
+				}
+			}
+			mcMu.Unlock()
+		}
+	}
+}