improved Delete func

db.go

@@ -2,42 +2,71 @@ package advsql
 
 import (
 	"database/sql"
+	"fmt"
 
 	_ "github.com/go-sql-driver/mysql"
 )
 
 type Database struct {
-	db         *sql.DB
+	db    *sql.DB
-	closefuncs []func() error
+	stmts map[string]*sql.Stmt
 }
 
-func NewDatabase(conn *sql.DB) *Database {
+func InitDatabase(database *Database, conn *sql.DB) {
-	return &Database{
+	panicOnNil(database)
-		db:         conn,
+
-		closefuncs: make([]func() error, 0),
+	if database.db != nil {
+		panic("database is initialized already")
 	}
+
+	*database = Database{
+		db:    conn,
+		stmts: map[string]*sql.Stmt{},
+	}
+	database.init()
 }
 
-func NewMysqlDatabase(host string, port uint16, user, pass, db string) *Database {
+func InitMysqlDatabase(database *Database, host string, port uint16, user, pass, db string) {
+	panicOnNil(database)
+
 	conn, err := sql.Open("mysql", connString(host, port, user, pass, db))
 	if err != nil {
 		panic(err)
 	}
-	return NewDatabase(conn)
+
+	InitDatabase(database, conn)
 }
 
-func (db *Database) prepare(query string) *sql.Stmt {
+func panicOnNil(database *Database) {
-	s, err := db.db.Prepare(query)
+	if database == nil {
-	if err != nil {
+		panic("database is nil. initialize database variable with new()")
-		panic(err)
 	}
-	db.closefuncs = append(db.closefuncs, s.Close)
+}
-	return s
+
+func (db *Database) init() {
+	for _, globalQuery := range globalStmts {
+		if db == globalQuery.db {
+			db.stmt(globalQuery.query)
+		}
+	}
+}
+
+func (db *Database) stmt(query string) *sql.Stmt {
+	if stmt, ok := db.stmts[query]; ok {
+		return stmt
+	}
+
+	stmt, err := db.db.Prepare(query)
+	if err != nil {
+		panic(fmt.Errorf("compilation failed for query '%s' reason: %w", query, err))
+	}
+	db.stmts[query] = stmt
+	return stmt
 }
 
 func (db *Database) Close() error {
-	for _, close := range db.closefuncs {
+	for _, stmt := range db.stmts {
-		close()
+		stmt.Close()
 	}
 	return db.db.Close()
 }

db_test.go

@@ -9,33 +9,31 @@ import (
 	_ "github.com/go-sql-driver/mysql"
 )
 
+var TestDatabase = new(Database)
+
 type User struct {
 	Name string
 	Hash []byte
 	Salt string
 }
 
-func UserDecoder(u *User, decode DecodeFunc) error {
+func ScanUserPkFirst(u *User, encode ScanFunc) error {
-	return decode(&u.Name, &u.Hash, &u.Salt)
+	return encode(&u.Name, &u.Hash, &u.Salt)
 }
 
-func InsertUserEncoder(u *User, encode EncodeFunc) error {
+func ScanUserPkLast(u *User, encode ScanFunc) error {
-	return encode(u.Name, u.Hash, u.Salt)
+	return encode(&u.Hash, &u.Salt, &u.Name)
 }
 
-func UpdateUserByNameEncoder(u *User, encode EncodeFunc) error {
+var (
-	return encode(u.Salt, u.Name)
+	InsertUser    = Insert(TestDatabase, "INSERT INTO users VALUES (?, ?, ?)", ScanUserPkFirst)
-}
+	UpdateUser    = Update(TestDatabase, "UPDATE users SET hash = ?, salt = ? WHERE name = ?", ScanUserPkLast)
+	GetUserByName = QueryOne(TestDatabase, "SELECT * FROM users WHERE namea = ?", ScanUserPkFirst)
+)
 
 func TestDB(t *testing.T) {
-	db := NewMysqlDatabase("ip", 3306, "username", "password", "database")
+	InitMysqlDatabase(TestDatabase, "ip", 3306, "username", "password", "database")
-	defer db.Close()
+	defer TestDatabase.Close()
-
-	insertUser := Insert(db, "INSERT INTO users VALUES (?, ?, ?)", InsertUserEncoder)
-
-	updateUser := Update(db, "UPDATE users SET salt = ? WHERE name = ?", UpdateUserByNameEncoder)
-
-	getUsers := QueryMany(db, "SELECT * FROM users WHERE name = ?", UserDecoder)
 
 	pw := sha512.Sum512([]byte("weiter"))
 	timon := &User{
@@ -43,13 +41,11 @@ func TestDB(t *testing.T) {
 		Hash: pw[:],
 		Salt: "salt",
 	}
-	fmt.Println("insert:", insertUser(timon))
+	fmt.Println("insert:", InsertUser(timon))
 
 	timon.Hash = []byte("asd")
-	fmt.Println("update:", updateUser(timon))
+	fmt.Println("update:", UpdateUser(timon))
-
-	for user := range getUsers("tordarus") {
-		fmt.Printf("name: \"%s\" | hash: \"%s\" | salt: \"%s\"\n", user.Name, hex.EncodeToString(user.Hash), user.Salt)
-	}
 
+	user := GetUserByName("tordarus")
+	fmt.Printf("name: \"%s\" | hash: \"%s\" | salt: \"%s\"\n", user.Name, hex.EncodeToString(user.Hash), user.Salt)
 }

default_decoders.go

@@ -7,6 +7,6 @@ type defaultDecoderType interface {
 }
 
 // Decoder provides default decoders for primitive datatypes
-func Decoder[T defaultDecoderType](value *T, decode DecodeFunc) error {
+func Decoder[T defaultDecoderType](value *T, decode ScanFunc) error {
 	return decode(value)
 }

delete.go

@@ -0,0 +1,11 @@
+package advsql
+
+func Delete(db *Database, query string) DeleteFunc {
+	prepareGlobal(db, query)
+
+	return func(args ...interface{}) error {
+		s := db.stmt(query)
+		_, err := s.Exec(args...)
+		return err
+	}
+}

func_types.go

@@ -10,3 +10,7 @@ type QueryOneContextFunc[T any] func(ctx context.Context, args ...interface{}) *
 
 type InsertFunc[T any] func(v *T) error
 type UpdateFunc[T any] func(v *T) error
+
+type DeleteFunc func(args ...interface{}) error
+
+type ScanFunc = func(args ...interface{}) error

global_stmts.go

@@ -0,0 +1,12 @@
+package advsql
+
+type globalStmt struct {
+	db    *Database
+	query string
+}
+
+var globalStmts = []*globalStmt{}
+
+func prepareGlobal(db *Database, query string) {
+	globalStmts = append(globalStmts, &globalStmt{db, query})
+}

go.mod

@@ -1,8 +1,5 @@
-module git.tordarus.net/Tordarus/advsql
+module git.milar.in/milarin/advsql
 
 go 1.18
 
-require (
+require github.com/go-sql-driver/mysql v1.6.0
-	git.tordarus.net/Tordarus/adverr v0.2.0
-	github.com/go-sql-driver/mysql v1.6.0
-)

go.sum

@@ -1,4 +1,2 @@
-git.tordarus.net/Tordarus/adverr v0.2.0 h1:kLYjR2/Vb2GHiSAMvAv+WPNaHR9BRphKanf8H/pCZdA=
-git.tordarus.net/Tordarus/adverr v0.2.0/go.mod h1:XRf0+7nhOkIEr0gi9DUG4RvV2KaOFB0fYPDaR1KLenw=
 github.com/go-sql-driver/mysql v1.6.0 h1:BCTh4TKNUYmOmMUcQ3IipzF5prigylS7XXjEkfCHuOE=
 github.com/go-sql-driver/mysql v1.6.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=

insert.go

@@ -1,9 +1,10 @@
 package advsql
 
-func Insert[T any](db *Database, query string, encoder func(v *T, encode EncodeFunc) error) InsertFunc[T] {
+func Insert[T any](db *Database, query string, encoder func(v *T, encode ScanFunc) error) InsertFunc[T] {
-	s := db.prepare(query)
+	prepareGlobal(db, query)
 
 	return func(value *T) error {
+		s := db.stmt(query)
 		return encoder(value, func(args ...interface{}) error {
 			_, err := s.Exec(args...)
 			return err

old/README.md

@@ -1,3 +0,0 @@
-# advsql
-
-A more advanced ORM for the Golang sql package

old/check_table_integrity.go

@@ -1,15 +0,0 @@
-package advsql
-
-func (s *Store) checkTableIntegrity(value interface{}) (bool, error) {
-	valueStructure, err := objectStructure(value)
-	if err != nil {
-		return false, err
-	}
-
-	tableStructure, err := s.tableStructure(valueStructure.TypeName)
-	if err != nil {
-		return false, err
-	}
-
-	return compareStructures(valueStructure, tableStructure), nil
-}

old/check_table_integrity_test.go

@@ -1,34 +0,0 @@
-package advsql
-
-import (
-	"log"
-	"testing"
-
-	_ "github.com/go-sql-driver/mysql"
-)
-
-func TestCheckTableIntegrity(t *testing.T) {
-	store, err := NewStoreMySQL("localhost", 3306, "kaikei", "u399D-TFulJykgRF4ijW6G7tK6zdO-jy", "kaikei")
-	if err != nil {
-		t.Fatal("could not make store", err)
-	}
-
-	type Person struct {
-		Surname  string
-		Lastname string
-		Age      int
-	}
-
-	p := &Person{
-		Surname:  "Timon",
-		Lastname: "Ringwald",
-		Age:      25,
-	}
-
-	integrity, err := store.checkTableIntegrity(p)
-	if err != nil {
-		t.Fatal("could not check table integrity", err)
-	}
-
-	log.Println("integrity:", integrity)
-}

old/create_table.go

@@ -1,96 +0,0 @@
-package advsql
-
-import (
-	"log"
-	"reflect"
-	"strings"
-)
-
-func (s *Store) createTable(structure *structure) error {
-	b := new(strings.Builder)
-	b.WriteString("CREATE TABLE ")
-	b.WriteString(structure.TypeName)
-	b.WriteString("(")
-
-	fieldAmount := len(structure.Fields)
-
-	for i, field := range structure.Fields {
-		b.WriteString(field.FieldName)
-		b.WriteString(" ")
-		b.WriteString(getTypeSpecForDB(field.FieldType))
-
-		if i < fieldAmount-1 {
-			b.WriteString(",")
-		}
-	}
-
-	b.WriteString(")")
-
-	log.Println("sql command: " + b.String())
-
-	_, err := s.db.Exec(b.String())
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func getTypeSpecForDB(t reflect.Type) string {
-	noPtrType := t
-	dereferenced := false
-
-	// derefence all pointers recursively
-	for noPtrType.Kind() == reflect.Ptr {
-		noPtrType = t.Elem()
-		dereferenced = true
-	}
-
-	// actual data types
-	b := new(strings.Builder)
-	switch noPtrType.Kind() {
-	case reflect.Bool:
-		b.WriteString("INT")
-
-	case reflect.Int:
-		b.WriteString("BIGINT")
-	case reflect.Int8:
-		b.WriteString("TINYINT")
-	case reflect.Int16:
-		b.WriteString("SMALLINT")
-	case reflect.Int32:
-		b.WriteString("INT")
-	case reflect.Int64:
-		b.WriteString("BIGINT")
-
-	case reflect.Uint:
-		b.WriteString("BIGINT UNSIGNED")
-	case reflect.Uint8:
-		b.WriteString("TINYINT UNSIGNED")
-	case reflect.Uint16:
-		b.WriteString("SMALLINT UNSIGNED")
-	case reflect.Uint32:
-		b.WriteString("INT UNSIGNED")
-	case reflect.Uint64:
-		b.WriteString("BIGINT UNSIGNED")
-
-	case reflect.Float32:
-		b.WriteString("FLOAT")
-	case reflect.Float64:
-		b.WriteString("DOUBLE")
-
-	case reflect.String:
-		b.WriteString("TEXT")
-
-	case reflect.Ptr:
-		panic("something's broken. All pointers should have been dereferenced by now")
-	default:
-		panic("type spec for db not implemented yet: " + noPtrType.Kind().String())
-	}
-
-	if !dereferenced {
-		b.WriteString(" NOT NULL")
-	}
-
-	return b.String()
-}

old/create_table_test.go

@@ -1,34 +0,0 @@
-package advsql
-
-import (
-	"testing"
-)
-
-func TestCreateTable(t *testing.T) {
-	store, err := NewStoreMySQL("localhost", 3306, "kaikei", "u399D-TFulJykgRF4ijW6G7tK6zdO-jy", "kaikei")
-	if err != nil {
-		t.Fatal("could not make store", err)
-	}
-
-	type Person struct {
-		Surname  string
-		Lastname string
-		Age      int
-	}
-
-	p := &Person{
-		Surname:  "Timon",
-		Lastname: "Ringwald",
-		Age:      25,
-	}
-
-	structure, err := objectStructure(p)
-	if err != nil {
-		t.Fatal("Could not get structure of value", err)
-	}
-
-	err = store.createTable(structure)
-	if err != nil {
-		t.Fatal("Could not create table", err)
-	}
-}

old/insert.go

@@ -1,11 +0,0 @@
-package advsql
-
-func (s *Store) Insert(value interface{}) error {
-	// structure, err := objectStructure(value)
-	// if err != nil {
-	// 	return err
-	// }
-
-	// return nil
-	return nil
-}

old/insert_test.go

@@ -1,27 +0,0 @@
-package advsql
-
-import "testing"
-
-func TestInsert(t *testing.T) {
-	store, err := NewStoreMySQL("localhost", 3306, "kaikei", "u399D-TFulJykgRF4ijW6G7tK6zdO-jy", "kaikei")
-	if err != nil {
-		t.Fatal("could not make store", err)
-	}
-
-	type Person struct {
-		Surname  string
-		Lastname string
-		Age      int
-	}
-
-	p := &Person{
-		Surname:  "Timon",
-		Lastname: "Ringwald",
-		Age:      25,
-	}
-
-	err = store.Insert(p)
-	if err != nil {
-		t.Fatal("Could not create table", err)
-	}
-}

old/object_structure.go

@@ -1,35 +0,0 @@
-package advsql
-
-import (
-	"reflect"
-	"errors"
-)
-
-var ErrNoStructure = errors.New("value is not of type structure")
-
-// analyze returns the structure of value
-func objectStructure(value interface{}) (*structure, error) {
-	t := reflect.TypeOf(value)
-	k := t.Kind()
-
-	// only structs are allowed to be stored in DB
-	// if pointer: dereference and check again via recursion
-	if k == reflect.Ptr {
-		v := reflect.ValueOf(value)
-		return objectStructure(reflect.Indirect(v).Interface())
-	} else if k != reflect.Struct {
-		return nil, ErrNoStructure
-	}
-
-	fieldAmount := t.NumField()
-	structure := new(structure)
-	structure.TypeName = t.Name()
-	structure.Fields = make([]field, fieldAmount)
-
-	for fieldIndex := 0; fieldIndex < fieldAmount; fieldIndex++ {
-		reflectField := t.Field(fieldIndex)
-		structure.Fields[fieldIndex] = makeFieldUsingReflect(reflectField)
-	}
-
-	return structure, nil
-}

old/store.go

@@ -1,47 +0,0 @@
-package advsql
-
-import (
-	"database/sql"
-	"fmt"
-)
-
-type Store struct {
-	db *sql.DB
-}
-
-func NewStoreMySQL(host string, port uint16, user, pass, db string) (*Store, error) {
-	dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s", user, pass, host, port, db)
-
-	conn, err := sql.Open("mysql", dsn)
-	if err != nil {
-		return nil, err
-	}
-
-	return NewStore(conn), nil
-}
-
-func NewStore(db *sql.DB) *Store {
-	return &Store{
-		db: db,
-	}
-}
-
-func (s *Store) Close() error {
-	stmts := []*sql.Stmt{}
-
-	var err error
-
-	for _, stmt := range stmts {
-		err = stmt.Close()
-		if err != nil {
-			return err
-		}
-	}
-
-	err = s.db.Close()
-	if err != nil {
-		return err
-	}
-
-	return nil
-}

old/table_structure.go

@@ -1,29 +0,0 @@
-package advsql
-
-func (s *Store) tableStructure(tableName string) (*structure, error) {
-	rows, err := s.db.Query("SELECT * FROM " + tableName)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	types, err := rows.ColumnTypes()
-	if err != nil {
-		return nil, err
-	}
-
-	structure := new(structure)
-	structure.TypeName = tableName
-
-	columnAmount := len(types)
-	structure.Fields = make([]field, columnAmount)
-
-	for columnIndex, columType := range types {
-		structure.Fields[columnIndex] = field{
-			FieldName: columType.Name(),
-			FieldType: columType.ScanType(),
-		}
-	}
-
-	return structure, nil
-}

old/types.go

@@ -1,94 +0,0 @@
-package advsql
-
-import (
-	"log"
-	"reflect"
-)
-
-type structure struct {
-	TypeName string
-	Fields   []field
-}
-
-type field struct {
-	FieldName string
-	FieldType reflect.Type
-}
-
-func makeFieldUsingReflect(reflectField reflect.StructField) field {
-	return field{
-		FieldName: reflectField.Name,
-		FieldType: reflectField.Type,
-	}
-}
-
-func compareStructures(first, second *structure) bool {
-	// compare names
-	if first.TypeName != second.TypeName {
-		log.Println("different names")
-		return false
-	}
-
-	firstFieldAmount, secondFieldAmount := len(first.Fields), len(second.Fields)
-
-	// compare field amounts
-	if firstFieldAmount != secondFieldAmount {
-		log.Println("different field amounts")
-		return false
-	}
-
-	// compare fields
-	for i := 0; i < firstFieldAmount; i++ {
-		firstField, secondField := first.Fields[i], second.Fields[i]
-		if !compareFields(firstField, secondField) {
-			log.Println("different field:", firstField, secondField)
-			return false
-		}
-	}
-
-	return true
-}
-
-func compareFields(first, second field) bool {
-	t1, t2 := first.FieldType, second.FieldType
-
-	// check if field names are equal
-	fieldNamesEqual := first.FieldName == second.FieldName
-
-	// exceptions for default comparison
-	switch true {
-	case checkBoth(first, second, isString, isByteSlice):
-		fallthrough
-	case isInt(first) && isInt(second):
-		fallthrough
-	case isUint(first) && isUint(second):
-		return fieldNamesEqual
-
-	default:
-		return t1 == t2
-	}
-}
-
-// TypeCheckFunc represents any function for type checking between Go and DB
-type TypeCheckFunc func(field) bool
-
-// checks if both check functions apply to either of the fields
-func checkBoth(first, second field, firstCheck, secondCheck TypeCheckFunc) bool {
-	return firstCheck(first) && secondCheck(second) || firstCheck(second) && secondCheck(first)
-}
-
-func isString(field field) bool {
-	return field.FieldType.Kind() == reflect.String
-}
-
-func isInt(field field) bool {
-	return field.FieldType.Kind() == reflect.Int || field.FieldType.Kind() == reflect.Int64
-}
-
-func isUint(field field) bool {
-	return field.FieldType.Kind() == reflect.Uint || field.FieldType.Kind() == reflect.Uint64
-}
-
-func isByteSlice(field field) bool {
-	return field.FieldType.Kind() == reflect.Slice && field.FieldType.Elem().Kind() == reflect.Uint8
-}

query_many.go

@@ -2,21 +2,19 @@ package advsql
 
 import "context"
 
-func QueryMany[T any](db *Database, query string, decoder func(v *T, decode DecodeFunc) error) QueryManyFunc[T] {
+func QueryMany[T any](db *Database, query string, decoder func(v *T, decode ScanFunc) error) QueryManyFunc[T] {
 	ctxfunc := QueryManyContext(db, query, decoder)
 	return func(args ...interface{}) <-chan *T {
 		return ctxfunc(context.Background(), args...)
 	}
 }
 
-func QueryManyContext[T any](db *Database, query string, decoder func(v *T, decode DecodeFunc) error) QueryManyContextFunc[T] {
+func QueryManyContext[T any](db *Database, query string, decoder func(v *T, decode ScanFunc) error) QueryManyContextFunc[T] {
-	s, err := db.db.Prepare(query)
+	prepareGlobal(db, query)
-	if err != nil {
-		return nil
-	}
-	db.closefuncs = append(db.closefuncs, s.Close)
 
 	return func(ctx context.Context, args ...interface{}) <-chan *T {
+		s := db.stmt(query)
+
 		out := make(chan *T, 10)
 
 		rows, err := s.QueryContext(ctx, args...)

query_one.go

@@ -2,14 +2,14 @@ package advsql
 
 import "context"
 
-func QueryOne[T any](db *Database, query string, decoder func(v *T, decode DecodeFunc) error) QueryOneFunc[T] {
+func QueryOne[T any](db *Database, query string, decoder func(v *T, decode ScanFunc) error) QueryOneFunc[T] {
 	ctxfunc := QueryOneContext(db, query, decoder)
 	return func(args ...interface{}) *T {
 		return ctxfunc(context.Background(), args...)
 	}
 }
 
-func QueryOneContext[T any](db *Database, query string, decoder func(v *T, decode DecodeFunc) error) QueryOneContextFunc[T] {
+func QueryOneContext[T any](db *Database, query string, decoder func(v *T, decode ScanFunc) error) QueryOneContextFunc[T] {
 	manyfunc := QueryManyContext(db, query, decoder)
 	return func(ctx context.Context, args ...interface{}) *T {
 		nctx, cancel := context.WithCancel(ctx)

scanner.go

@@ -1,4 +0,0 @@
-package advsql
-
-type DecodeFunc func(args ...interface{}) error
-type EncodeFunc func(args ...interface{}) error

stmt.go

@@ -1,59 +0,0 @@
-package advsql
-
-// import (
-// 	"database/sql"
-// )
-
-// type Stmt[M any] struct {
-// 	stmt *sql.Stmt
-// 	scan func(Scanner) (*M, error)
-// }
-
-// func NewStmt[M any](db *Database, query string, scan func(s Scanner) (*M, error)) (*Stmt[M], error) {
-// 	s, err := db.db.Prepare(query)
-// 	if err != nil {
-// 		return nil, err
-// 	}
-
-// 	stmt := Stmt[M]{
-// 		stmt: s,
-// 		scan: scan,
-// 	}
-// 	db.closefuncs = append(db.closefuncs, stmt.Close)
-// 	return &stmt, err
-// }
-
-// func (stmt *Stmt[M]) Close() error {
-// 	return stmt.stmt.Close()
-// }
-
-// func (stmt *Stmt[M]) Many(args ...interface{}) (<-chan *M, error) {
-// 	rows, err := stmt.stmt.Query(args...)
-// 	if err != nil {
-// 		return nil, err
-// 	}
-
-// 	out := make(chan *M, 10)
-
-// 	go func() {
-// 		defer rows.Close()
-// 		defer close(out)
-
-// 		for rows.Next() {
-// 			if v, err := stmt.scan(rows); err == nil {
-// 				out <- v
-// 			}
-// 		}
-// 	}()
-
-// 	return out, nil
-// }
-
-// func (stmt *Stmt[M]) Single(args ...interface{}) (*M, error) {
-// 	rows, err := stmt.stmt.Query(args...)
-// 	if err != nil {
-// 		return nil, err
-// 	}
-// 	defer rows.Close()
-// 	return stmt.scan(rows)
-// }

update.go

@@ -1,5 +1,5 @@
 package advsql
 
-func Update[T any](db *Database, query string, encoder func(v *T, encode EncodeFunc) error) UpdateFunc[T] {
+func Update[T any](db *Database, query string, encoder func(v *T, encode ScanFunc) error) UpdateFunc[T] {
 	return UpdateFunc[T](Insert(db, query, encoder))
 }