Crate actix_web_grants

A crate for validate user permissions in actix-web.

For built-in configure see: GrantsMiddleware.

To check user access to specific services, you can use: proc-macro and PermissionGuard or manual.

The library can also be integrated with third-party solutions (like httpauth), see permissions module.

You can find more examples in the git repository.

actix-web-grants

Extension for actix-web to validate user permissions.

To check user access to specific services, you can use built-in proc-macro, PermissionGuard or manual.

The library can also be integrated with third-party solutions (like actix-web-httpauth).

How to use

1. Declare your own permission extractor

The easiest way is to declare a function with the following signature (trait is already implemented for such Fn):

use actix_web::{dev::ServiceRequest, Error};

// You can use custom type instead of String
async fn extract(req: &ServiceRequest) -> Result<Vec<String>, Error>

2. Add middleware to your application using the extractor defined in step 1

App::new()
    .wrap(GrantsMiddleware::with_extractor(extract))

Steps 1 and 2 can be replaced by custom middleware or integration with another libraries. Take a look at an jwt-httpauth example

3. Protect your endpoints in any convenient way from the examples below:

Example of proc-macro way protection

use actix_web_grants::proc_macro::{has_permissions};

#[get("/secure")]
#[has_permissions("OP_READ_SECURED_INFO")]
async fn macro_secured() -> HttpResponse {
    HttpResponse::Ok().body("ADMIN_RESPONSE")
}

Example of ABAC-like protection and custom permission type

Here is an example using the type and secure attributes. But these are independent features.

secure allows you to include some checks in the macro based on function params.

type allows you to use a custom type for the roles and permissions (then the middleware needs to be configured). Take a look at an enum-role example

use actix_web_grants::proc_macro::{has_role};
use enums::Role::{self, ADMIN};
use dto::User;

#[get("/info/{user_id}")]
#[has_role("ADMIN", type = "Role", secure = "user_id.into_inner() == user.id")]
async fn macro_secured(user_id: web::Path<i32>, user: web::Data<User>) -> HttpResponse {
    HttpResponse::Ok().body("some secured response")
}

Example of Guard way protection

use actix_web_grants::{PermissionGuard, GrantsMiddleware};

App::new()
    .wrap(GrantsMiddleware::with_extractor(extract))
    .service(web::resource("/admin")
            .to(|| async { HttpResponse::Ok().finish() })
            .guard(PermissionGuard::new("ROLE_ADMIN".to_string())))
    .service(web::resource("/admin") // fallback endpoint if you want to return a 403 HTTP code 
            .to(|| async { HttpResponse::Forbidden().finish() }))

Example of custom fallback endpoint for `Scope` with `Guard`

Since Guard is intended only for routing, if the user doesn’t have permissions, it returns a 404 HTTP code. But you can override the behavior like this:

use actix_web_grants::{PermissionGuard, GrantsMiddleware};
use actix_web::http::header;

App::new()
    .wrap(GrantsMiddleware::with_extractor(extract))
    .service(web::scope("/admin")
        .guard(PermissionGuard::new("ROLE_ADMIN_ACCESS".to_string()))
        .service(web::resource("/users")
            .to(|| async { HttpResponse::Ok().finish() }))
    ).service(
        web::resource("/admin{regex:$|/.*?}").to(|| async { 
            HttpResponse::TemporaryRedirect().append_header((header::LOCATION, "/login")).finish()
        }))

When Guard lets you in the Scope (meaning you have "ROLE_ADMIN_ACCESS"), the redirect will be unreachable for you. Even if you will request /admin/some_undefined_page.

Note: regex is a Path variable containing passed link.

Example of manual way protection

use actix_web_grants::permissions::{AuthDetails, PermissionsCheck};

async fn manual_secure(details: AuthDetails) -> HttpResponse {
    if details.has_permission(ROLE_ADMIN) {
        return HttpResponse::Ok().body("ADMIN_RESPONSE");
    }
    HttpResponse::Ok().body("OTHER_RESPONSE")
}

You can find more examples in the git repository folder and documentation.

Supported actix-web versions

• For actix-web-grants: 2.* supported version of actix-web is 3.*
• For actix-web-grants: 3.* supported version of actix-web is 4.*

Modules

• permissions
  A set of traits and structures for custom integration.
• proc_macro
  Procedural macros for checking user permissions or roles.

Structs

• GrantsMiddleware
  Built-in middleware for extracting user permission.
• PermissionGuard
  Implementation of Guard trait for validate permissions