gorm/callbacks/query.go

125 lines
3.3 KiB
Go

package callbacks
import (
"fmt"
"reflect"
"github.com/jinzhu/gorm"
"github.com/jinzhu/gorm/clause"
)
func Query(db *gorm.DB) {
if db.Statement.SQL.String() == "" {
clauseSelect := clause.Select{}
if len(db.Statement.Selects) > 0 {
for _, name := range db.Statement.Selects {
if f := db.Statement.Schema.LookUpField(name); f != nil {
clauseSelect.Columns = append(clauseSelect.Columns, clause.Column{
Name: f.DBName,
})
}
}
}
if len(db.Statement.Joins) != 0 {
joins := []clause.Join{}
if len(db.Statement.Selects) == 0 {
for _, dbName := range db.Statement.Schema.DBNames {
clauseSelect.Columns = append(clauseSelect.Columns, clause.Column{
Table: db.Statement.Table,
Name: dbName,
})
}
}
for name, conds := range db.Statement.Joins {
if relation, ok := db.Statement.Schema.Relationships.Relations[name]; ok {
for _, s := range relation.FieldSchema.DBNames {
clauseSelect.Columns = append(clauseSelect.Columns, clause.Column{
Table: relation.Name,
Name: s,
Alias: relation.Name + "__" + s,
})
}
var exprs []clause.Expression
for _, ref := range relation.References {
if ref.OwnPrimaryKey {
exprs = append(exprs, clause.Expr{
SQL: fmt.Sprintf("%s.%s = %s.%s", db.Statement.Schema.Table, ref.PrimaryKey.DBName, relation.Name, ref.ForeignKey.DBName),
})
} else {
if ref.PrimaryValue == "" {
exprs = append(exprs, clause.Expr{
SQL: fmt.Sprintf("%s.%s = %s.%s", db.Statement.Schema.Table, ref.ForeignKey.DBName, relation.Name, ref.PrimaryKey.DBName),
})
} else {
exprs = append(exprs, clause.Expr{
SQL: fmt.Sprintf("%s.%s = ?", relation.Name, ref.PrimaryKey.DBName),
Vars: []interface{}{ref.PrimaryValue},
})
}
}
}
joins = append(joins, clause.Join{
Type: clause.LeftJoin,
Table: clause.Table{Name: relation.FieldSchema.Table, Alias: relation.Name},
ON: clause.Where{Exprs: exprs},
})
} else {
joins = append(joins, clause.Join{
Expression: clause.Expr{SQL: name, Vars: conds},
})
}
}
db.Statement.AddClause(clause.From{Joins: joins})
} else {
db.Statement.AddClauseIfNotExists(clause.From{})
}
db.Statement.AddClauseIfNotExists(clauseSelect)
db.Statement.Build("SELECT", "FROM", "WHERE", "GROUP BY", "ORDER BY", "LIMIT", "FOR")
}
rows, err := db.Statement.ConnPool.QueryContext(db.Statement.Context, db.Statement.SQL.String(), db.Statement.Vars...)
if err != nil {
db.AddError(err)
return
}
defer rows.Close()
Scan(rows, db)
}
func Preload(db *gorm.DB) {
}
func AfterQuery(db *gorm.DB) {
if db.Statement.Schema != nil && db.Statement.Schema.AfterFind {
callMethod := func(value interface{}) bool {
if db.Statement.Schema.AfterFind {
if i, ok := value.(gorm.AfterFindInterface); ok {
i.AfterFind(db)
return true
}
}
return false
}
if ok := callMethod(db.Statement.Dest); !ok {
switch db.Statement.ReflectValue.Kind() {
case reflect.Slice, reflect.Array:
for i := 0; i <= db.Statement.ReflectValue.Len(); i++ {
callMethod(db.Statement.ReflectValue.Index(i).Interface())
}
case reflect.Struct:
callMethod(db.Statement.ReflectValue.Interface())
}
}
}
}