Gorm Adapter
In v3.0.3, method
NewAdapterByDB
creates table namedcasbin_rules
,
we fix it tocasbin_rule
after that.
If you used v3.0.3 and less, and you want to update it,
you might need to migrate data manually. Find out more at: #78
Gorm Adapter is the Gorm adapter for Casbin. With this library, Casbin can load policy from Gorm supported database or save policy to it.
Based on Officially Supported Databases, The current supported databases are:
- MySQL
- PostgreSQL
- SQL Server
- Sqlite3
gorm-adapter use
github.com/glebarez/sqlite
instead of gorm official sqlite drivergorm.io/driver/sqlite
because the latter needscgo
support. But there is almost no difference between the two driver. If there is a difference in use, please submit an issue.
- other 3rd-party supported DBs in Gorm website or other places.
Installation
go get github.com/casbin/gorm-adapter/v3
Simple Example
package main
import (
"github.com/casbin/casbin/v2"
gormadapter "github.com/casbin/gorm-adapter/v3"
_ "github.com/go-sql-driver/mysql"
)
func main() {
// Initialize a Gorm adapter and use it in a Casbin enforcer:
// The adapter will use the MySQL database named "casbin".
// If it doesn't exist, the adapter will create it automatically.
// You can also use an already existing gorm instance with gormadapter.NewAdapterByDB(gormInstance)
a, _ := gormadapter.NewAdapter("mysql", "mysql_username:mysql_password@tcp(127.0.0.1:3306)/") // Your driver and data source.
e, _ := casbin.NewEnforcer("examples/rbac_model.conf", a)
// Or you can use an existing DB "abc" like this:
// The adapter will use the table named "casbin_rule".
// If it doesn't exist, the adapter will create it automatically.
// a := gormadapter.NewAdapter("mysql", "mysql_username:mysql_password@tcp(127.0.0.1:3306)/abc", true)
// Load the policy from DB.
e.LoadPolicy()
// Check the permission.
e.Enforce("alice", "data1", "read")
// Modify the policy.
// e.AddPolicy(...)
// e.RemovePolicy(...)
// Save the policy back to DB.
e.SavePolicy()
}
Turn off AutoMigrate
New an adapter will use AutoMigrate
by default for create table, if you want to turn it off, please use API TurnOffAutoMigrate(db *gorm.DB) *gorm.DB
. See example:
db, err := gorm.Open(mysql.Open("root:@tcp(127.0.0.1:3306)/casbin"), &gorm.Config{})
TurnOffAutoMigrate(db)
// a,_ := NewAdapterByDB(...)
// a,_ := NewAdapterByDBUseTableName(...)
a,_ := NewAdapterByDBWithCustomTable(...)
Find out more details at gorm-adapter#162
Customize table columns example
You can change the gorm struct tags, but the table structure must stay the same.
package main
import (
"github.com/casbin/casbin/v2"
gormadapter "github.com/casbin/gorm-adapter/v3"
"gorm.io/gorm"
)
func main() {
// Increase the column size to 512.
type CasbinRule struct {
ID uint `gorm:"primaryKey;autoIncrement"`
Ptype string `gorm:"size:512;uniqueIndex:unique_index"`
V0 string `gorm:"size:512;uniqueIndex:unique_index"`
V1 string `gorm:"size:512;uniqueIndex:unique_index"`
V2 string `gorm:"size:512;uniqueIndex:unique_index"`
V3 string `gorm:"size:512;uniqueIndex:unique_index"`
V4 string `gorm:"size:512;uniqueIndex:unique_index"`
V5 string `gorm:"size:512;uniqueIndex:unique_index"`
}
db, _ := gorm.Open(...)
// Initialize a Gorm adapter and use it in a Casbin enforcer:
// The adapter will use an existing gorm.DB instnace.
a, _ := gormadapter.NewAdapterByDBWithCustomTable(db, &CasbinRule{})
e, _ := casbin.NewEnforcer("examples/rbac_model.conf", a)
// Load the policy from DB.
e.LoadPolicy()
// Check the permission.
e.Enforce("alice", "data1", "read")
// Modify the policy.
// e.AddPolicy(...)
// e.RemovePolicy(...)
// Save the policy back to DB.
e.SavePolicy()
}
Transaction
You can modify policies within a transaction.See example:
package main
func main() {
a, err := NewAdapterByDB(db)
e, _ := casbin.NewEnforcer("examples/rbac_model.conf", a)
err = e.GetAdapter().(*Adapter).Transaction(e, func(e casbin.IEnforcer) error {
_, err := e.AddPolicy("jack", "data1", "write")
if err != nil {
return err
}
_, err = e.AddPolicy("jack", "data2", "write")
if err != nil {
return err
}
return nil
})
if err != nil {
// handle if transaction failed
return
}
}
ConditionsToGormQuery
ConditionsToGormQuery()
is a function that converts multiple query conditions into a GORM query statement
You can use the GetAllowedObjectConditions()
API of Casbin to get conditions,
and choose the way of combining conditions through combineType
.
ConditionsToGormQuery()
allows Casbin to be combined with SQL, and you can use it to implement many functions.
Example: GetAllowedRecordsForUser
- model example: object_conditions_model.conf
- policy example: object_conditions_policy.csv
DataBase example:
id | title | author | publisher | publish_data | price | category_id |
---|---|---|---|---|---|---|
1 | book1 | author1 | publisher1 | 2023-04-09 16:23:42 | 10 | 1 |
2 | book2 | author1 | publisher1 | 2023-04-09 16:23:44 | 20 | 2 |
3 | book3 | author2 | publisher1 | 2023-04-09 16:23:44 | 30 | 1 |
4 | book4 | author2 | publisher2 | 2023-04-09 16:23:45 | 10 | 3 |
5 | book5 | author3 | publisher2 | 2023-04-09 16:23:45 | 50 | 1 |
6 | book6 | author3 | publisher2 | 2023-04-09 16:23:46 | 60 | 2 |
type Book struct {
ID int
Title string
Author string
Publisher string
PublishDate time.Time
Price float64
CategoryID int
}
func TestGetAllowedRecordsForUser(t *testing.T) {
e, _ := casbin.NewEnforcer("examples/object_conditions_model.conf", "examples/object_conditions_policy.csv")
conditions, err := e.GetAllowedObjectConditions("alice", "read", "r.obj.")
if err != nil {
panic(err)
}
fmt.Println(conditions)
dsn := "root:root@tcp(127.0.0.1:3307)/test?charset=utf8mb4&parseTime=True&loc=Local"
db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})
if err != nil {
panic(err)
}
fmt.Println("CombineTypeOr")
rows, err := ConditionsToGormQuery(db, conditions, CombineTypeOr).Model(&Book{}).Rows()
defer rows.Close()
var b Book
for rows.Next() {
err := db.ScanRows(rows, &b)
if err != nil {
panic(err)
}
log.Println(b)
}
fmt.Println("CombineTypeAnd")
rows, err = ConditionsToGormQuery(db, conditions, CombineTypeAnd).Model(&Book{}).Rows()
defer rows.Close()
for rows.Next() {
err := db.ScanRows(rows, &b)
if err != nil {
panic(err)
}
log.Println(b)
}
}
Getting Help
License
This project is under Apache 2.0 License. See the LICENSE file for the full license text.