Move db related basic functions to models/db (#17075)

* Move db related basic functions to models/db

* Fix lint

* Fix lint

* Fix test

* Fix lint

* Fix lint

* revert unnecessary change

* Fix test

* Fix wrong replace string

* Use *Context

* Correct committer spelling and fix wrong replaced words

Co-authored-by: zeripath <art27@cantab.net>

models/db/engine.go

@@ -0,0 +1,297 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Copyright 2018 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package db
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+
+	"code.gitea.io/gitea/modules/setting"
+
+	// Needed for the MySQL driver
+	_ "github.com/go-sql-driver/mysql"
+	"xorm.io/xorm"
+	"xorm.io/xorm/names"
+	"xorm.io/xorm/schemas"
+
+	// Needed for the Postgresql driver
+	_ "github.com/lib/pq"
+
+	// Needed for the MSSQL driver
+	_ "github.com/denisenkom/go-mssqldb"
+)
+
+var (
+	x         *xorm.Engine
+	tables    []interface{}
+	initFuncs []func() error
+
+	// HasEngine specifies if we have a xorm.Engine
+	HasEngine bool
+)
+
+// Engine represents a xorm engine or session.
+type Engine interface {
+	Table(tableNameOrBean interface{}) *xorm.Session
+	Count(...interface{}) (int64, error)
+	Decr(column string, arg ...interface{}) *xorm.Session
+	Delete(...interface{}) (int64, error)
+	Exec(...interface{}) (sql.Result, error)
+	Find(interface{}, ...interface{}) error
+	Get(interface{}) (bool, error)
+	ID(interface{}) *xorm.Session
+	In(string, ...interface{}) *xorm.Session
+	Incr(column string, arg ...interface{}) *xorm.Session
+	Insert(...interface{}) (int64, error)
+	InsertOne(interface{}) (int64, error)
+	Iterate(interface{}, xorm.IterFunc) error
+	Join(joinOperator string, tablename interface{}, condition string, args ...interface{}) *xorm.Session
+	SQL(interface{}, ...interface{}) *xorm.Session
+	Where(interface{}, ...interface{}) *xorm.Session
+	Asc(colNames ...string) *xorm.Session
+	Desc(colNames ...string) *xorm.Session
+	Limit(limit int, start ...int) *xorm.Session
+	SumInt(bean interface{}, columnName string) (res int64, err error)
+	Sync2(...interface{}) error
+	Select(string) *xorm.Session
+	NotIn(string, ...interface{}) *xorm.Session
+	OrderBy(string) *xorm.Session
+	Exist(...interface{}) (bool, error)
+	Distinct(...string) *xorm.Session
+	Query(...interface{}) ([]map[string][]byte, error)
+	Cols(...string) *xorm.Session
+}
+
+// TableInfo returns table's information via an object
+func TableInfo(v interface{}) (*schemas.Table, error) {
+	return x.TableInfo(v)
+}
+
+// DumpTables dump tables information
+func DumpTables(tables []*schemas.Table, w io.Writer, tp ...schemas.DBType) error {
+	return x.DumpTables(tables, w, tp...)
+}
+
+// RegisterModel registers model, if initfunc provided, it will be invoked after data model sync
+func RegisterModel(bean interface{}, initFunc ...func() error) {
+	tables = append(tables, bean)
+	if len(initFuncs) > 0 && initFunc[0] != nil {
+		initFuncs = append(initFuncs, initFunc[0])
+	}
+}
+
+func init() {
+	gonicNames := []string{"SSL", "UID"}
+	for _, name := range gonicNames {
+		names.LintGonicMapper[name] = true
+	}
+}
+
+// GetNewEngine returns a new xorm engine from the configuration
+func GetNewEngine() (*xorm.Engine, error) {
+	connStr, err := setting.DBConnStr()
+	if err != nil {
+		return nil, err
+	}
+
+	var engine *xorm.Engine
+
+	if setting.Database.UsePostgreSQL && len(setting.Database.Schema) > 0 {
+		// OK whilst we sort out our schema issues - create a schema aware postgres
+		registerPostgresSchemaDriver()
+		engine, err = xorm.NewEngine("postgresschema", connStr)
+	} else {
+		engine, err = xorm.NewEngine(setting.Database.Type, connStr)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+	if setting.Database.Type == "mysql" {
+		engine.Dialect().SetParams(map[string]string{"rowFormat": "DYNAMIC"})
+	} else if setting.Database.Type == "mssql" {
+		engine.Dialect().SetParams(map[string]string{"DEFAULT_VARCHAR": "nvarchar"})
+	}
+	engine.SetSchema(setting.Database.Schema)
+	return engine, nil
+}
+
+func syncTables() error {
+	return x.StoreEngine("InnoDB").Sync2(tables...)
+}
+
+// NewTestEngine sets a new test xorm.Engine
+func NewTestEngine() (err error) {
+	x, err = GetNewEngine()
+	if err != nil {
+		return fmt.Errorf("Connect to database: %v", err)
+	}
+
+	x.SetMapper(names.GonicMapper{})
+	x.SetLogger(NewXORMLogger(!setting.IsProd()))
+	x.ShowSQL(!setting.IsProd())
+	return syncTables()
+}
+
+// SetEngine sets the xorm.Engine
+func SetEngine() (err error) {
+	x, err = GetNewEngine()
+	if err != nil {
+		return fmt.Errorf("Failed to connect to database: %v", err)
+	}
+
+	x.SetMapper(names.GonicMapper{})
+	// WARNING: for serv command, MUST remove the output to os.stdout,
+	// so use log file to instead print to stdout.
+	x.SetLogger(NewXORMLogger(setting.Database.LogSQL))
+	x.ShowSQL(setting.Database.LogSQL)
+	x.SetMaxOpenConns(setting.Database.MaxOpenConns)
+	x.SetMaxIdleConns(setting.Database.MaxIdleConns)
+	x.SetConnMaxLifetime(setting.Database.ConnMaxLifetime)
+	return nil
+}
+
+// NewEngine initializes a new xorm.Engine
+// This function must never call .Sync2() if the provided migration function fails.
+// When called from the "doctor" command, the migration function is a version check
+// that prevents the doctor from fixing anything in the database if the migration level
+// is different from the expected value.
+func NewEngine(ctx context.Context, migrateFunc func(*xorm.Engine) error) (err error) {
+	if err = SetEngine(); err != nil {
+		return err
+	}
+
+	x.SetDefaultContext(ctx)
+
+	if err = x.Ping(); err != nil {
+		return err
+	}
+
+	if err = migrateFunc(x); err != nil {
+		return fmt.Errorf("migrate: %v", err)
+	}
+
+	if err = syncTables(); err != nil {
+		return fmt.Errorf("sync database struct error: %v", err)
+	}
+
+	for _, initFunc := range initFuncs {
+		if err := initFunc(); err != nil {
+			return fmt.Errorf("initFunc failed: %v", err)
+		}
+	}
+
+	return nil
+}
+
+// NamesToBean return a list of beans or an error
+func NamesToBean(names ...string) ([]interface{}, error) {
+	beans := []interface{}{}
+	if len(names) == 0 {
+		beans = append(beans, tables...)
+		return beans, nil
+	}
+	// Need to map provided names to beans...
+	beanMap := make(map[string]interface{})
+	for _, bean := range tables {
+
+		beanMap[strings.ToLower(reflect.Indirect(reflect.ValueOf(bean)).Type().Name())] = bean
+		beanMap[strings.ToLower(x.TableName(bean))] = bean
+		beanMap[strings.ToLower(x.TableName(bean, true))] = bean
+	}
+
+	gotBean := make(map[interface{}]bool)
+	for _, name := range names {
+		bean, ok := beanMap[strings.ToLower(strings.TrimSpace(name))]
+		if !ok {
+			return nil, fmt.Errorf("No table found that matches: %s", name)
+		}
+		if !gotBean[bean] {
+			beans = append(beans, bean)
+			gotBean[bean] = true
+		}
+	}
+	return beans, nil
+}
+
+// Ping tests if database is alive
+func Ping() error {
+	if x != nil {
+		return x.Ping()
+	}
+	return errors.New("database not configured")
+}
+
+// DumpDatabase dumps all data from database according the special database SQL syntax to file system.
+func DumpDatabase(filePath, dbType string) error {
+	var tbs []*schemas.Table
+	for _, t := range tables {
+		t, err := x.TableInfo(t)
+		if err != nil {
+			return err
+		}
+		tbs = append(tbs, t)
+	}
+
+	type Version struct {
+		ID      int64 `xorm:"pk autoincr"`
+		Version int64
+	}
+	t, err := x.TableInfo(&Version{})
+	if err != nil {
+		return err
+	}
+	tbs = append(tbs, t)
+
+	if len(dbType) > 0 {
+		return x.DumpTablesToFile(tbs, filePath, schemas.DBType(dbType))
+	}
+	return x.DumpTablesToFile(tbs, filePath)
+}
+
+// MaxBatchInsertSize returns the table's max batch insert size
+func MaxBatchInsertSize(bean interface{}) int {
+	t, err := x.TableInfo(bean)
+	if err != nil {
+		return 50
+	}
+	return 999 / len(t.ColumnsSeq())
+}
+
+// Count returns records number according struct's fields as database query conditions
+func Count(bean interface{}) (int64, error) {
+	return x.Count(bean)
+}
+
+// IsTableNotEmpty returns true if table has at least one record
+func IsTableNotEmpty(tableName string) (bool, error) {
+	return x.Table(tableName).Exist()
+}
+
+// DeleteAllRecords will delete all the records of this table
+func DeleteAllRecords(tableName string) error {
+	_, err := x.Exec(fmt.Sprintf("DELETE FROM %s", tableName))
+	return err
+}
+
+// GetMaxID will return max id of the table
+func GetMaxID(beanOrTableName interface{}) (maxID int64, err error) {
+	_, err = x.Select("MAX(id)").Table(beanOrTableName).Get(&maxID)
+	return
+}
+
+// FindByMaxID filled results as the condition from database
+func FindByMaxID(maxID int64, limit int, results interface{}) error {
+	return x.Where("id <= ?", maxID).
+		OrderBy("id DESC").
+		Limit(limit).
+		Find(results)
+}