package main import ( "context" "errors" "github.com/yuin/gopher-lua" ) const luaSecurityTypeName = "security" func luaContextGetSecurities(L *lua.LState) (map[int64]*Security, error) { var security_map map[int64]*Security ctx := L.Context() security_map, ok := ctx.Value(securitiesContextKey).(map[int64]*Security) if !ok { user, ok := ctx.Value(userContextKey).(*User) if !ok { return nil, errors.New("Couldn't find User in lua's Context") } securities, err := GetSecurities(user.UserId) if err != nil { return nil, err } security_map = make(map[int64]*Security) for i := range *securities { security_map[(*securities)[i].SecurityId] = (*securities)[i] } ctx = context.WithValue(ctx, securitiesContextKey, security_map) L.SetContext(ctx) } return security_map, nil } func luaGetSecurities(L *lua.LState) int { security_map, err := luaContextGetSecurities(L) if err != nil { panic("luaGetSecurities couldn't fetch securities") } table := L.NewTable() for securityid := range security_map { table.RawSetInt(int(securityid), SecurityToLua(L, security_map[securityid])) } L.Push(table) return 1 } // Registers my security type to given L. func luaRegisterSecurities(L *lua.LState) { mt := L.NewTypeMetatable(luaSecurityTypeName) L.SetGlobal("security", mt) L.SetField(mt, "__index", L.NewFunction(luaSecurity__index)) L.SetField(mt, "__tostring", L.NewFunction(luaSecurity__tostring)) L.SetField(mt, "__eq", L.NewFunction(luaSecurity__eq)) L.SetField(mt, "__metatable", lua.LString("protected")) getSecuritiesFn := L.NewFunction(luaGetSecurities) L.SetField(mt, "get_all", getSecuritiesFn) // also register the get_securities function as a global in its own right L.SetGlobal("get_securities", getSecuritiesFn) } func SecurityToLua(L *lua.LState, security *Security) *lua.LUserData { ud := L.NewUserData() ud.Value = security L.SetMetatable(ud, L.GetTypeMetatable(luaSecurityTypeName)) return ud } // Checks whether the first lua argument is a *LUserData with *Security and returns this *Security. func luaCheckSecurity(L *lua.LState, n int) *Security { ud := L.CheckUserData(n) if security, ok := ud.Value.(*Security); ok { return security } L.ArgError(n, "security expected") return nil } func luaSecurity__index(L *lua.LState) int { a := luaCheckSecurity(L, 1) field := L.CheckString(2) switch field { case "SecurityId", "securityid": L.Push(lua.LNumber(float64(a.SecurityId))) case "Name", "name": L.Push(lua.LString(a.Name)) case "Description", "description": L.Push(lua.LString(a.Description)) case "Symbol", "symbol": L.Push(lua.LString(a.Symbol)) case "Precision", "precision": L.Push(lua.LNumber(float64(a.Precision))) case "Type", "type": L.Push(lua.LNumber(float64(a.Type))) default: L.ArgError(2, "unexpected security attribute: "+field) } return 1 } func luaSecurity__tostring(L *lua.LState) int { s := luaCheckSecurity(L, 1) L.Push(lua.LString(s.Name + " - " + s.Description + " (" + s.Symbol + ")")) return 1 } func luaSecurity__eq(L *lua.LState) int { a := luaCheckSecurity(L, 1) b := luaCheckSecurity(L, 2) L.Push(lua.LBool(a.SecurityId == b.SecurityId)) return 1 }