gf/database/gdb/gdb_model.go
2020-04-11 10:11:52 +08:00

202 lines
6.4 KiB
Go

// Copyright 2017 gf Author(https://github.com/gogf/gf). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package gdb
import (
"fmt"
"github.com/gogf/gf/text/gregex"
"time"
"github.com/gogf/gf/text/gstr"
)
// Model is the DAO for ORM.
type Model struct {
db DB // Underlying DB interface.
tx *TX // Underlying TX interface.
schema string // Custom database schema.
linkType int // Mark for operation on master or slave.
tablesInit string // Table names when model initialization.
tables string // Operation table names, which can be more than one table names and aliases, like: "user", "user u", "user u, user_detail ud".
fields string // Operation fields, multiple fields joined using char ','.
fieldsEx string // Excluded operation fields, multiple fields joined using char ','.
extraArgs []interface{} // Extra custom arguments for sql.
whereHolder []*whereHolder // Condition strings for where operation.
groupBy string // Used for "group by" statement.
orderBy string // Used for "order by" statement.
having []interface{} // Used for "having..." statement.
start int // Used for "select ... start, limit ..." statement.
limit int // Used for "select ... start, limit ..." statement.
option int // Option for extra operation features.
offset int // Offset statement for some databases grammar.
data interface{} // Data for operation, which can be type of map/[]map/struct/*struct/string, etc.
batch int // Batch number for batch Insert/Replace/Save operations.
filter bool // Filter data and where key-value pairs according to the fields of the table.
lockInfo string // Lock for update or in shared lock.
cacheEnabled bool // Enable sql result cache feature.
cacheDuration time.Duration // Cache TTL duration.
cacheName string // Cache name for custom operation.
unscoped bool // Disables soft deleting features when select/delete operations.
safe bool // If true, it clones and returns a new model object whenever operation done; or else it changes the attribute of current model.
}
// whereHolder is the holder for where condition preparing.
type whereHolder struct {
operator int // Operator for this holder.
where interface{} // Where parameter.
args []interface{} // Arguments for where parameter.
}
const (
gLINK_TYPE_MASTER = 1
gLINK_TYPE_SLAVE = 2
gWHERE_HOLDER_WHERE = 1
gWHERE_HOLDER_AND = 2
gWHERE_HOLDER_OR = 3
OPTION_OMITEMPTY = 1 << iota
OPTION_ALLOWEMPTY
)
// Table creates and returns a new ORM model from given schema.
// The parameter <table> can be more than one table names, and also alias name, like:
// 1. Table names:
// Table("user")
// Table("user u")
// Table("user, user_detail")
// Table("user u, user_detail ud")
// 2. Table name with alias: Table("user", "u")
func (c *Core) Table(table ...string) *Model {
tables := ""
if len(table) > 1 {
tables = fmt.Sprintf(
`%s AS %s`, c.DB.QuotePrefixTableName(table[0]), c.DB.QuoteWord(table[1]),
)
} else if len(table) == 1 {
tables = c.DB.QuotePrefixTableName(table[0])
} else {
panic("table cannot be empty")
}
return &Model{
db: c.DB,
tablesInit: tables,
tables: tables,
fields: "*",
start: -1,
offset: -1,
option: OPTION_ALLOWEMPTY,
}
}
// Model is alias of Core.Table.
// See Core.Table.
func (c *Core) Model(table ...string) *Model {
return c.DB.Table(table...)
}
// Table acts like Core.Table except it operates on transaction.
// See Core.Table.
func (tx *TX) Table(table ...string) *Model {
model := tx.db.Table(table...)
model.db = tx.db
model.tx = tx
return model
}
// Model is alias of tx.Table.
// See tx.Table.
func (tx *TX) Model(table ...string) *Model {
return tx.Table(table...)
}
// As sets an alias name for current table.
func (m *Model) As(as string) *Model {
if m.tables != "" {
model := m.getModel()
split := " JOIN "
if gstr.Contains(model.tables, split) {
// For join table.
array := gstr.Split(model.tables, split)
array[len(array)-1], _ = gregex.ReplaceString(`(.+) ON`, fmt.Sprintf(`$1 AS %s ON`, as), array[len(array)-1])
model.tables = gstr.Join(array, split)
} else {
// For base table.
model.tables = gstr.TrimRight(model.tables) + " AS " + as
}
return model
}
return m
}
// DB sets/changes the db object for current operation.
func (m *Model) DB(db DB) *Model {
model := m.getModel()
model.db = db
return model
}
// TX sets/changes the transaction for current operation.
func (m *Model) TX(tx *TX) *Model {
model := m.getModel()
model.tx = tx
return model
}
// Schema sets the schema for current operation.
func (m *Model) Schema(schema string) *Model {
model := m.getModel()
model.schema = schema
return model
}
// Clone creates and returns a new model which is a clone of current model.
// Note that it uses deep-copy for the clone.
func (m *Model) Clone() *Model {
newModel := (*Model)(nil)
if m.tx != nil {
newModel = m.tx.Table(m.tablesInit)
} else {
newModel = m.db.Table(m.tablesInit)
}
*newModel = *m
// Deep copy slice attributes.
if n := len(m.extraArgs); n > 0 {
newModel.extraArgs = make([]interface{}, n)
copy(newModel.extraArgs, m.extraArgs)
}
if n := len(m.whereHolder); n > 0 {
newModel.whereHolder = make([]*whereHolder, n)
copy(newModel.whereHolder, m.whereHolder)
}
return newModel
}
// Master marks the following operation on master node.
func (m *Model) Master() *Model {
model := m.getModel()
model.linkType = gLINK_TYPE_MASTER
return model
}
// Slave marks the following operation on slave node.
// Note that it makes sense only if there's any slave node configured.
func (m *Model) Slave() *Model {
model := m.getModel()
model.linkType = gLINK_TYPE_SLAVE
return model
}
// Safe marks this model safe or unsafe. If safe is true, it clones and returns a new model object
// whenever the operation done, or else it changes the attribute of current model.
func (m *Model) Safe(safe ...bool) *Model {
if len(safe) > 0 {
m.safe = safe[0]
} else {
m.safe = true
}
return m
}