add sqlite support

internal/server/sv1/lua_handler.go

@@ -3,6 +3,7 @@ package sv1
 // TODO: make a lua state pool using sync.Pool
 
 import (
+	"database/sql"
 	"fmt"
 	"io"
 	"log/slog"
@@ -12,12 +13,322 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"sync"
 
 	"github.com/akyaiy/GoSally-mvp/internal/colors"
 	"github.com/akyaiy/GoSally-mvp/internal/server/rpc"
 	lua "github.com/yuin/gopher-lua"
+	_ "modernc.org/sqlite"
 )
 
+type DBConnection struct {
+	dbPath    string
+	log       bool
+	logger    *slog.Logger
+	writeChan chan *dbWriteRequest
+	closeChan chan struct{}
+}
+
+type dbWriteRequest struct {
+	query string
+	args  []interface{}
+	resCh chan *dbWriteResult
+}
+
+type dbWriteResult struct {
+	rowsAffected int64
+	err          error
+}
+
+var dbMutexMap = make(map[string]*sync.RWMutex)
+var dbGlobalMutex sync.Mutex
+
+func getDBMutex(dbPath string) *sync.RWMutex {
+	dbGlobalMutex.Lock()
+	defer dbGlobalMutex.Unlock()
+
+	if mtx, ok := dbMutexMap[dbPath]; ok {
+		return mtx
+	}
+
+	mtx := &sync.RWMutex{}
+	dbMutexMap[dbPath] = mtx
+	return mtx
+}
+
+func loadDBMod(llog *slog.Logger) func(*lua.LState) int {
+	llog.Debug("import module db-sqlite")
+	return func(L *lua.LState) int {
+		dbMod := L.NewTable()
+
+		L.SetField(dbMod, "connect", L.NewFunction(func(L *lua.LState) int {
+			dbPath := L.CheckString(1)
+
+			logQueries := false
+			if L.GetTop() >= 2 {
+				opts := L.CheckTable(2)
+				if val := opts.RawGetString("log"); val != lua.LNil {
+					logQueries = lua.LVAsBool(val)
+				}
+			}
+
+			conn := &DBConnection{
+				dbPath:    dbPath,
+				log:       logQueries,
+				logger:    llog,
+				writeChan: make(chan *dbWriteRequest, 100),
+				closeChan: make(chan struct{}),
+			}
+
+			go conn.processWrites()
+
+			ud := L.NewUserData()
+			ud.Value = conn
+			L.SetMetatable(ud, L.GetTypeMetatable("gosally_db"))
+
+			L.Push(ud)
+			return 1
+		}))
+
+		mt := L.NewTypeMetatable("gosally_db")
+		L.SetField(mt, "__index", L.SetFuncs(L.NewTable(), map[string]lua.LGFunction{
+			"exec":  dbExec,
+			"query": dbQuery,
+			"close": dbClose,
+		}))
+
+		L.SetField(dbMod, "__gosally_internal", lua.LString("0"))
+		L.Push(dbMod)
+		return 1
+	}
+}
+
+func (conn *DBConnection) processWrites() {
+	for {
+		select {
+		case req := <-conn.writeChan:
+			mtx := getDBMutex(conn.dbPath)
+			mtx.Lock()
+
+			db, err := sql.Open("sqlite", conn.dbPath+"?_busy_timeout=5000&_journal_mode=WAL&_sync=NORMAL&_cache_size=-10000")
+			if err == nil {
+				_, err = db.Exec("PRAGMA journal_mode=WAL;")
+				if err == nil {
+					res, execErr := db.Exec(req.query, req.args...)
+					if execErr == nil {
+						rows, _ := res.RowsAffected()
+						req.resCh <- &dbWriteResult{rowsAffected: rows}
+					} else {
+						req.resCh <- &dbWriteResult{err: execErr}
+					}
+				}
+				db.Close()
+			}
+
+			if err != nil {
+				req.resCh <- &dbWriteResult{err: err}
+			}
+
+			mtx.Unlock()
+		case <-conn.closeChan:
+			return
+		}
+	}
+}
+
+func dbExec(L *lua.LState) int {
+	ud := L.CheckUserData(1)
+	conn, ok := ud.Value.(*DBConnection)
+	if !ok {
+		L.Push(lua.LNil)
+		L.Push(lua.LString("invalid database connection"))
+		return 2
+	}
+
+	query := L.CheckString(2)
+	
+	var args []any
+	if L.GetTop() >= 3 {
+		params := L.CheckTable(3)
+		params.ForEach(func(k lua.LValue, v lua.LValue) {
+			args = append(args, ConvertLuaTypesToGolang(v))
+		})
+	}
+
+	if conn.log {
+		conn.logger.Info("DB Exec",
+			slog.String("query", query),
+			slog.Any("params", args))
+	}
+
+	resCh := make(chan *dbWriteResult, 1)
+	conn.writeChan <- &dbWriteRequest{
+		query: query,
+		args:  args,
+		resCh: resCh,
+	}
+
+	ctx := L.NewTable()
+	L.SetField(ctx, "done", lua.LBool(false))
+	
+	var result lua.LValue = lua.LNil
+	var errorMsg lua.LValue = lua.LNil
+
+	L.SetField(ctx, "wait", L.NewFunction(func(lL *lua.LState) int {
+		res := <-resCh
+		L.SetField(ctx, "done", lua.LBool(true))
+		
+		if res.err != nil {
+			errorMsg = lua.LString(res.err.Error())
+			result = lua.LNil
+		} else {
+			result = lua.LNumber(res.rowsAffected)
+			errorMsg = lua.LNil
+		}
+		
+		if res.err != nil {
+			lL.Push(lua.LNil)
+			lL.Push(lua.LString(res.err.Error()))
+			return 2
+		}
+		lL.Push(lua.LNumber(res.rowsAffected))
+		lL.Push(lua.LNil)
+		return 2
+	}))
+
+	L.SetField(ctx, "check", L.NewFunction(func(lL *lua.LState) int {
+		select {
+		case res := <-resCh:
+			lL.SetField(ctx, "done", lua.LBool(true))
+			if res.err != nil {
+				errorMsg = lua.LString(res.err.Error())
+				result = lua.LNil
+				lL.Push(lua.LNil)
+				lL.Push(lua.LString(res.err.Error()))
+				return 2
+			} else {
+				result = lua.LNumber(res.rowsAffected)
+				errorMsg = lua.LNil
+				lL.Push(lua.LNumber(res.rowsAffected))
+				lL.Push(lua.LNil)
+				return 2
+			}
+		default:
+			lL.Push(result)
+			lL.Push(errorMsg)
+			return 2
+		}
+	}))
+
+	L.Push(ctx)
+	L.Push(lua.LNil)
+	return 2
+}
+
+func dbQuery(L *lua.LState) int {
+	ud := L.CheckUserData(1)
+	conn, ok := ud.Value.(*DBConnection)
+	if !ok {
+		L.Push(lua.LNil)
+		L.Push(lua.LString("invalid database connection"))
+		return 2
+	}
+
+	query := L.CheckString(2)
+
+	var args []any
+	if L.GetTop() >= 3 {
+		params := L.CheckTable(3)
+		params.ForEach(func(k lua.LValue, v lua.LValue) {
+			args = append(args, ConvertLuaTypesToGolang(v))
+		})
+	}
+
+	if conn.log {
+		conn.logger.Info("DB Query",
+			slog.String("query", query),
+			slog.Any("params", args))
+	}
+
+	mtx := getDBMutex(conn.dbPath)
+	mtx.RLock()
+	defer mtx.RUnlock()
+
+	db, err := sql.Open("sqlite", conn.dbPath+"?_busy_timeout=5000&_journal_mode=WAL&_sync=NORMAL&_cache_size=-10000")
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(err.Error()))
+		return 2
+	}
+	defer db.Close()
+
+	rows, err := db.Query(query, args...)
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("query failed: %v", err)))
+		return 2
+	}
+	defer rows.Close()
+
+	columns, err := rows.Columns()
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("get columns failed: %v", err)))
+		return 2
+	}
+
+	result := L.NewTable()
+	colCount := len(columns)
+	values := make([]any, colCount)
+	valuePtrs := make([]any, colCount)
+
+	for rows.Next() {
+		for i := range columns {
+			valuePtrs[i] = &values[i]
+		}
+
+		if err := rows.Scan(valuePtrs...); err != nil {
+			L.Push(lua.LNil)
+			L.Push(lua.LString(fmt.Sprintf("scan failed: %v", err)))
+			return 2
+		}
+
+		rowTable := L.NewTable()
+		for i, col := range columns {
+			val := values[i]
+			if val == nil {
+				L.SetField(rowTable, col, lua.LNil)
+			} else {
+				L.SetField(rowTable, col, ConvertGolangTypesToLua(L, val))
+			}
+		}
+		result.Append(rowTable)
+	}
+
+	if err := rows.Err(); err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("rows iteration failed: %v", err)))
+		return 2
+	}
+
+	L.Push(result)
+	return 1
+}
+
+func dbClose(L *lua.LState) int {
+	ud := L.CheckUserData(1)
+	conn, ok := ud.Value.(*DBConnection)
+	if !ok {
+		L.Push(lua.LFalse)
+		L.Push(lua.LString("invalid database connection"))
+		return 2
+	}
+
+	close(conn.closeChan)
+	L.Push(lua.LTrue)
+	return 1
+}
+
 func addInitiatorHeaders(sid string, req *http.Request, headers http.Header) {
 	clientIP := req.RemoteAddr
 	if forwardedFor := req.Header.Get("X-Forwarded-For"); forwardedFor != "" {
@@ -38,14 +349,15 @@ func addInitiatorHeaders(sid string, req *http.Request, headers http.Header) {
 // I will be only glad.
 // TODO: make this huge function more harmonious by dividing responsibilities
 func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest, path string) *rpc.RPCResponse {
-	h.x.SLog.Debug("handling LUA", slog.String("session-id", sid))
+	llog := h.x.SLog.With(slog.String("session-id", sid))
+	llog.Debug("handling LUA")
 	L := lua.NewState()
 	defer L.Close()
 
 	seed := rand.Int()
 
 	loadSessionMod := func(lL *lua.LState) int {
-		h.x.SLog.Debug("import module session", slog.String("script", path))
+		llog.Debug("import module session", slog.String("script", path))
 		sessionMod := lL.NewTable()
 		inTable := lL.NewTable()
 		paramsTable := lL.NewTable()
@@ -60,6 +372,7 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 		resultTable := lL.NewTable()
 		lL.SetField(outTable, "result", resultTable)
 
+		lL.SetField(inTable, "address", lua.LString(r.RemoteAddr))
 		lL.SetField(sessionMod, "request", inTable)
 		lL.SetField(sessionMod, "response", outTable)
 
@@ -71,14 +384,14 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 	}
 
 	loadLogMod := func(lL *lua.LState) int {
-		h.x.SLog.Debug("import module log", slog.String("script", path))
+		llog.Debug("import module log", slog.String("script", path))
 		logMod := lL.NewTable()
 
 		logFuncs := map[string]func(string, ...any){
-			"info":  h.x.SLog.Info,
-			"debug": h.x.SLog.Debug,
-			"error": h.x.SLog.Error,
-			"warn":  h.x.SLog.Warn,
+			"info":  llog.Info,
+			"debug": llog.Debug,
+			"error": llog.Error,
+			"warn":  llog.Warn,
 		}
 
 		for name, logFunc := range logFuncs {
@@ -118,7 +431,7 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 	}
 
 	loadNetMod := func(lL *lua.LState) int {
-		h.x.SLog.Debug("import module net", slog.String("script", path))
+		llog.Debug("import module net", slog.String("script", path))
 		netMod := lL.NewTable()
 		netModhttp := lL.NewTable()
 
@@ -152,7 +465,7 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 			}
 
 			if logRequest {
-				h.x.SLog.Info("HTTP GET request",
+				llog.Info("HTTP GET request",
 					slog.String("script", path),
 					slog.String("url", url),
 					slog.Int("status", resp.StatusCode),
@@ -213,7 +526,7 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 			}
 
 			if logRequest {
-				h.x.SLog.Info("HTTP POST request",
+				llog.Info("HTTP POST request",
 					slog.String("script", path),
 					slog.String("url", url),
 					slog.String("content_type", contentType),
@@ -249,32 +562,33 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 	L.PreloadModule("internal.session", loadSessionMod)
 	L.PreloadModule("internal.log", loadLogMod)
 	L.PreloadModule("internal.net", loadNetMod)
+	L.PreloadModule("internal.database-sqlite", loadDBMod(llog))
 
-	h.x.SLog.Debug("preparing environment", slog.String("session-id", sid))
+	llog.Debug("preparing environment")
 	prep := filepath.Join(*h.x.Config.Conf.Node.ComDir, "_prepare.lua")
 	if _, err := os.Stat(prep); err == nil {
 		if err := L.DoFile(prep); err != nil {
-			h.x.SLog.Error("script error", slog.String("script", path), slog.String("error", err.Error()))
+			llog.Error("script error", slog.String("script", path), slog.String("error", err.Error()))
 			return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)
 		}
 	}
-	h.x.SLog.Debug("executing script", slog.String("script", path), slog.String("session-id", sid))
+	llog.Debug("executing script", slog.String("script", path))
 	if err := L.DoFile(path); err != nil {
-		h.x.SLog.Error("script error", slog.String("script", path), slog.String("error", err.Error()))
+		llog.Error("script error", slog.String("script", path), slog.String("error", err.Error()))
 		return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)
 	}
 
 	pkg := L.GetGlobal("package")
 	pkgTbl, ok := pkg.(*lua.LTable)
 	if !ok {
-		h.x.SLog.Error("script error", slog.String("script", path), slog.String("error", "package not found"))
+		llog.Error("script error", slog.String("script", path), slog.String("error", "package not found"))
 		return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)
 	}
 
 	loaded := pkgTbl.RawGetString("loaded")
 	loadedTbl, ok := loaded.(*lua.LTable)
 	if !ok {
-		h.x.SLog.Error("script error", slog.String("script", path), slog.String("error", "package.loaded not found"))
+		llog.Error("script error", slog.String("script", path), slog.String("error", "package.loaded not found"))
 		return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)
 	}
 
@@ -288,7 +602,7 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 
 	tag := sessionTbl.RawGetString("__gosally_internal")
 	if tag.Type() != lua.LTString || tag.String() != fmt.Sprint(seed) {
-		h.x.SLog.Debug("stock session module is not imported: wrong seed", slog.String("script", path), slog.String("session-id", sid))
+		llog.Debug("stock session module is not imported: wrong seed", slog.String("script", path))
 		return rpc.NewResponse(map[string]any{
 			"responsible-node": h.cs.UUID32,
 		}, req.ID)
@@ -297,12 +611,12 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 	outVal := sessionTbl.RawGetString("response")
 	outTbl, ok := outVal.(*lua.LTable)
 	if !ok {
-		h.x.SLog.Error("script error", slog.String("script", path), slog.String("error", "response is not a table"))
+		llog.Error("script error", slog.String("script", path), slog.String("error", "response is not a table"))
 		return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)
 	}
 
 	if errVal := outTbl.RawGetString("error"); errVal != lua.LNil {
-		h.x.SLog.Debug("catch error table", slog.String("script", path), slog.String("session-id", sid))
+		llog.Debug("catch error table", slog.String("script", path))
 		if errTbl, ok := errVal.(*lua.LTable); ok {
 			code := rpc.ErrInternalError
 			message := rpc.ErrInternalErrorS
@@ -318,10 +632,10 @@ func (h *HandlerV1) handleLUA(sid string, r *http.Request, req *rpc.RPCRequest,
 			if tbl, ok := rawData.(*lua.LTable); ok {
 				tbl.ForEach(func(k, v lua.LValue) { data[k.String()] = ConvertLuaTypesToGolang(v) })
 			} else {
-				h.x.SLog.Error("the script terminated with an error", slog.String("code", strconv.Itoa(code)), slog.String("message", message))
-				return rpc.NewError(code, message, rawData, req.ID)
+				llog.Error("the script terminated with an error", slog.String("code", strconv.Itoa(code)), slog.String("message", message))
+				return rpc.NewError(code, message, ConvertLuaTypesToGolang(rawData), req.ID)
 			}
-			h.x.SLog.Error("the script terminated with an error", slog.String("code", strconv.Itoa(code)), slog.String("message", message))
+			llog.Error("the script terminated with an error", slog.String("code", strconv.Itoa(code)), slog.String("message", message))
 			return rpc.NewError(code, message, data, req.ID)
 		}
 		return rpc.NewError(rpc.ErrInternalError, rpc.ErrInternalErrorS, nil, req.ID)