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Gorm Adapter Ex

This gorm-adapter-ex is an extended version of Gorm-Adapter. It introduces great and implements proposal of customizability by reflection. The database structure can be arbitrary as long as it has {"ID", "Ptype", "V0"} three fields.

	type TestCasbinRule struct { //arbitrary number of variable fields
		ID    uint   `gorm:"primaryKey;autoIncrement"`
		Ptype string `gorm:"size:16"`
		V0    string `gorm:"size:128"`
		V1    string `gorm:"size:128"`
		V2    string `gorm:"size:256"`
		DeletedAt gorm.DeletedAt
	}

	// Create an adapter
	a, _ := NewAdapterByDBWithCustomTable(db, &TestCasbinRule{}, "test_casbin_rule")
	//...

Background for why we create a new fork:

casbin/gorm-adapter#179 (comment)

casbin/gorm-adapter#168 (comment)

About Gorm Adapter

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 driver gorm.io/driver/sqlite because the latter needs cgo 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()
}

Getting Help

License

This project is under Apache 2.0 License. See the LICENSE file for the full license text.