authz

README

Negroni-authz

Negroni-authz is an authorization middleware for Negroni, it's based on https://github.com/casbin/casbin.

Installation

go get github.com/casbin/negroni-authz

Simple Example

package main

import (
    "fmt"
    "net/http"

    "github.com/casbin/casbin"
    "github.com/casbin/negroni-authz"
    "github.com/urfave/negroni"
)

func main() {
    mux := http.NewServeMux()
    mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
        fmt.Fprintf(w, "Welcome to the home page!")
    })

    n := negroni.Classic()

    // load the casbin model and policy from files, database is also supported.
    e := casbin.NewEnforcer("authz_model.conf", "authz_policy.csv")
    n.Use(authz.Authorizer(e))

    http.ListenAndServe(":3000", n)
}

How to control the access

The authorization determines a request based on {subject, object, action}, which means what subject can perform what action on what object. In this plugin, the meanings are:

1. subject: the logged-on user name
2. object: the URL path for the web resource like "dataset1/item1"
3. action: HTTP method like GET, POST, PUT, DELETE, or the high-level actions you defined like "read-file", "write-blog"

For how to write authorization policy and other details, please refer to the Casbin's documentation.

Getting Help

• Casbin

License

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

Documentation

Index

• func Authorizer(e *casbin.Enforcer) negroni.HandlerFunc
• func CheckPermission(e *casbin.Enforcer, r *http.Request) bool
• func GetUserName(r *http.Request) string

Functions

func Authorizer

func Authorizer(e *casbin.Enforcer) negroni.HandlerFunc

Authz is a middleware that controls the access to the HTTP service, it is based on Casbin, which supports access control models like ACL, RBAC, ABAC. The plugin determines whether to allow a request based on (user, path, method). user: the authenticated user name. path: the URL for the requested resource. method: one of HTTP methods like GET, POST, PUT, DELETE.

This middleware should be inserted fairly early in the middleware stack to protect subsequent layers. All the denied requests will not go further.

It's notable that this middleware should be behind the authentication (e.g., HTTP basic authentication, OAuth), so this plugin can get the logged-in user name to perform the authorization.

func CheckPermission

func CheckPermission(e *casbin.Enforcer, r *http.Request) bool

CheckPermission checks the user/method/path combination from the request. Returns true (permission granted) or false (permission forbidden)

func GetUserName

func GetUserName(r *http.Request) string

GetUserName gets the user name from the request. Currently, only HTTP basic authentication is supported