Get Started

Instalação

Go

go get github.com/casbin/casbin/v2

Java

Para Maven:

<!-- https://mvnrepository.com/artifact/org.casbin/jcasbin -->
<dependency>
    <groupId>org.casbin</groupId>
    <artifactId>jcasbin</artifactId>
    <version>1.x.y</version>
</dependency>

GraalVM Native Image Support

If you're building a native application with GraalVM (e.g., using Quarkus or Spring Native), jCasbin requires special configuration due to its use of the Aviator expression engine.

By default, Aviator uses dynamic class generation via ASM, which is not supported in GraalVM native images. To resolve this, you must configure Aviator to use interpreter mode instead of compilation mode.

For Quarkus applications:

Add the following to your application.properties or pom.xml:

<properties>
    <quarkus.native.additional-build-args>
        -J-Daviator.eval.mode=INTERPRETER
    </quarkus.native.additional-build-args>
</properties>

For other GraalVM native builds:

Set the system property when building the native image:

-Daviator.eval.mode=INTERPRETER

Or configure it programmatically before initializing jCasbin:

System.setProperty("aviator.eval.mode", "INTERPRETER");

nota

This configuration switches Aviator from its default compilation mode to interpreter mode. While this may have a slight performance impact, it enables full compatibility with GraalVM native images by avoiding runtime class generation.

Node.js

# NPM
npm install casbin --save

# Yarn
yarn add casbin

PHP

Requisite este pacote no composer.json do seu projeto para baixar o pacote:

composer require casbin/casbin

Python

pip install casbin

.NET

dotnet add package Casbin.NET

C++

# Download source
git clone https://github.com/casbin/casbin-cpp.git

# Generate project files
cd casbin-cpp && mkdir build && cd build && cmake .. -DCMAKE_BUILD_TYPE=Release

# Build and install casbin
cmake --build . --config Release --target casbin install -j 10

Rust

cargo install cargo-edit
cargo add casbin

// If you use async-std as async executor
cargo add async-std

// If you use tokio as async executor, make sure you activate its `macros` feature
cargo add tokio

Delphi

Casbin4D vem em um pacote (atualmente para Delphi 10.3 Rio) e você pode instalá-lo na IDE. No entanto, não há componentes visuais, o que significa que você pode usar as unidades independentemente dos pacotes. Basta importar as unidades no seu projeto (assumindo que você não se importa com o número delas).

Lua

luarocks install casbin

Se você receber uma mensagem de erro: "Seu usuário não tem permissões de escrita em /usr/local/lib/luarocks/rocks", você pode querer executar o comando como um usuário privilegiado ou usar sua árvore local com --local. Para corrigir o erro, você pode adicionar --local atrás do seu comando assim:

luarocks install casbin --local

Crie um executor do Casbin

O Casbin usa arquivos de configuração para definir o modelo de controle de acesso.

Há dois arquivos de configuração: model.conf e policy.csv. model.conf armazena o modelo de acesso, enquanto policy.csv armazena a configuração específica de permissão do usuário. O uso do Casbin é muito simples. Só precisamos criar uma estrutura principal: enforcer. Ao construir esta estrutura, model.conf e policy.csv serão carregados.

Em outras palavras, para criar um executor do Casbin, você precisa fornecer um Model e um Adapter.

O Casbin fornece um FileAdapter que você pode usar. Veja Adapter para mais informações.

• Exemplo de uso do arquivo Model e do FileAdapter padrão:

Go

import "github.com/casbin/casbin/v2"

e, err := casbin.NewEnforcer("path/to/model.conf", "path/to/policy.csv")

Java

import org.casbin.jcasbin.main.Enforcer;

Enforcer e = new Enforcer("path/to/model.conf", "path/to/policy.csv");

Node.js

import { newEnforcer } from 'casbin';

const e = await newEnforcer('path/to/model.conf', 'path/to/policy.csv');

PHP

require_once './vendor/autoload.php';

use Casbin\Enforcer;

$e = new Enforcer("path/to/model.conf", "path/to/policy.csv");

Python

import casbin

e = casbin.Enforcer("path/to/model.conf", "path/to/policy.csv")

.NET

using NetCasbin;

var e = new Enforcer("path/to/model.conf", "path/to/policy.csv");

C++

#include <iostream>
#include <casbin/casbin.h>

int main() {
    // Create an Enforcer
    casbin::Enforcer e("path/to/model.conf", "path/to/policy.csv");

    // your code ..
}

Delphi

var
  casbin: ICasbin;
begin
  casbin := TCasbin.Create('path/to/model.conf', 'path/to/policy.csv');
  ...
end

Rust

use casbin::prelude::*;

// If you use async_td as async executor
#[cfg(feature = "runtime-async-std")]
#[async_std::main]
async fn main() -> Result<()> {
    let mut e = Enforcer::new("path/to/model.conf", "path/to/policy.csv").await?;
    Ok(())
}

// If you use tokio as async executor
#[cfg(feature = "runtime-tokio")]
#[tokio::main]
async fn main() -> Result<()> {
    let mut e = Enforcer::new("path/to/model.conf", "path/to/policy.csv").await?;
    Ok(())
}

Lua

local Enforcer = require("casbin")
local e = Enforcer:new("path/to/model.conf", "path/to/policy.csv") -- The Casbin Enforcer

• Use o texto do Model com outro Adapter:

Go

import (
    "log"

    "github.com/casbin/casbin/v2"
    "github.com/casbin/casbin/v2/model"
    xormadapter "github.com/casbin/xorm-adapter/v2"
    _ "github.com/go-sql-driver/mysql"
)

// Initialize a Xorm adapter with MySQL database.
a, err := xormadapter.NewAdapter("mysql", "mysql_username:mysql_password@tcp(127.0.0.1:3306)/")
if err != nil {
    log.Fatalf("error: adapter: %s", err)
}

m, err := model.NewModelFromString(`
[request_definition]
r = sub, obj, act

[policy_definition]
p = sub, obj, act

[policy_effect]
e = some(where (p.eft == allow))

[matchers]
m = r.sub == p.sub && r.obj == p.obj && r.act == p.act
`)
if err != nil {
    log.Fatalf("error: model: %s", err)
}

e, err := casbin.NewEnforcer(m, a)
if err != nil {
    log.Fatalf("error: enforcer: %s", err)
}

Python

import casbin
import casbin_sqlalchemy_adapter


# Use SQLAlchemy Casbin adapter with SQLLite DB
adapter = casbin_sqlalchemy_adapter.Adapter('sqlite:///test.db')

# Create a config model policy
with open("rbac_example_model.conf", "w") as f:
    f.write("""
    [request_definition]
    r = sub, obj, act

    [policy_definition]
    p = sub, obj, act

    [policy_effect]
    e = some(where (p.eft == allow))

    [matchers]
    m = r.sub == p.sub && r.obj == p.obj && r.act == p.act
    """)

# Create enforcer from adapter and config policy
e = casbin.Enforcer('rbac_example_model.conf', adapter)

Verificar permissões

Adicione um gancho de execução no seu código logo antes do acesso acontecer:

Go

sub := "alice" // the user that wants to access a resource.
obj := "data1" // the resource that is going to be accessed.
act := "read" // the operation that the user performs on the resource.

ok, err := e.Enforce(sub, obj, act)

if err != nil {
    // handle err
}

if ok == true {
    // permit alice to read data1
} else {
    // deny the request, show an error
}

// You could use BatchEnforce() to enforce some requests in batches.
// This method returns a bool slice, and this slice's index corresponds to the row index of the two-dimensional array.
// e.g. results[0] is the result of {"alice", "data1", "read"}
results, err := e.BatchEnforce([][]interface{}{{"alice", "data1", "read"}, {"bob", "data2", "write"}, {"jack", "data3", "read"}})

Java

String sub = "alice"; // the user that wants to access a resource.
String obj = "data1"; // the resource that is going to be accessed.
String act = "read"; // the operation that the user performs on the resource.

if (e.enforce(sub, obj, act) == true) {
    // permit alice to read data1
} else {
    // deny the request, show an error
}

GraalVM Native Image Note

If you're running jCasbin in a GraalVM native image environment, make sure you've configured Aviator to use interpreter mode as described in the installation section above. Without this configuration, you'll encounter an UnsupportedFeatureError due to runtime class generation attempts.

Node.js

const sub = 'alice'; // the user that wants to access a resource.
const obj = 'data1'; // the resource that is going to be accessed.
const act = 'read'; // the operation that the user performs on the resource.

if ((await e.enforce(sub, obj, act)) === true) {
    // permit alice to read data1
} else {
    // deny the request, show an error
}

PHP

$sub = "alice"; // the user that wants to access a resource.
$obj = "data1"; // the resource that is going to be accessed.
$act = "read"; // the operation that the user performs on the resource.

if ($e->enforce($sub, $obj, $act) === true) {
    // permit alice to read data1
} else {
    // deny the request, show an error
}

Python

sub = "alice"  # the user that wants to access a resource.
obj = "data1"  # the resource that is going to be accessed.
act = "read"  # the operation that the user performs on the resource.

if e.enforce(sub, obj, act):
    # permit alice to read data1
    pass
else:
    # deny the request, show an error
    pass

.NET

var sub = "alice";  # the user that wants to access a resource.
var obj = "data1";  # the resource that is going to be accessed.
var act = "read";  # the operation that the user performs on the resource.

if (await e.EnforceAsync(sub, obj, act))
{
    // permit alice to read data1
}
else
{
    // deny the request, show an error
}

C++

    casbin::Enforcer e("../assets/model.conf", "../assets/policy.csv");

    if (e.Enforce({"alice", "/alice_data/hello", "GET"})) {
        std::cout << "Enforce OK" << std::endl;
    } else {
        std::cout << "Enforce NOT Good" << std::endl;
    }

    if (e.Enforce({"alice", "/alice_data/hello", "POST"})) {
        std::cout << "Enforce OK" << std::endl;
    } else {
        std::cout << "Enforce NOT Good" << std::endl;
    }

Delphi

if casbin.enforce(['alice,data1,read']) then
  // Alice is super happy as she can read data1
else
  // Alice is sad

Rust

  let sub = "alice"; // the user that wants to access a resource.
  let obj = "data1"; // the resource that is going to be accessed.
  let act = "read"; // the operation that the user performs on the resource.

  if e.enforce((sub, obj, act)).await? {
      // permit alice to read data1
  } else {
      // error occurs
  }

Lua

if e:enforce("alice", "data1", "read") then
   -- permit alice to read data1
else
   -- deny the request, show an error
end

O Casbin também fornece API para gerenciamento de permissões em tempo de execução. Por exemplo, Você pode obter todos os papéis atribuídos a um usuário como abaixo:

Go

roles, err := e.GetRolesForUser("alice")

Java

List<String> roles = e.getRolesForUser("alice");

Node.js

const roles = await e.getRolesForUser('alice');

PHP

$roles = $e->getRolesForUser("alice");

Python

roles = e.get_roles_for_user("alice")

.NET

var roles = e.GetRolesForUser("alice");

Delphi

roles = e.rolesForEntity("alice")

Rust

let roles = e.get_roles_for_user("alice");

Lua

local roles = e:GetRolesForUser("alice")

Veja Management API e RBAC API para mais usos.

Por favor, consulte os casos de teste para mais usos.