8 minutes
GSoC: Week 5
Tasks:
✅ casbin-example respository multiple depencies version conflict resolve
🟩 Real-life example for Axum middleware
Outcomes
-
casbin-example:
tokio and async-std conflict resolved
fix: Update tokio -
axum-middleware-example:
filestructure and initial db implementation
Workflow
casbin-example
Tokio reimport error(after resolving error in actix-casbin and actix-casbin-auth):
error[E0252]: the name `IoError` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:20:10
|
13 | io::{BufReader, Error as IoError, ErrorKind},
| ---------------- previous import of the type `IoError` here
...
20 | io::{Error as IoError, ErrorKind},
| ^^^^^^^^^^^^^^^^--
| |
| `IoError` reimported here
| help: remove unnecessary import
|
= note: `IoError` must be defined only once in the type namespace of this module
error[E0252]: the name `ErrorKind` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:20:28
|
13 | io::{BufReader, Error as IoError, ErrorKind},
| --------- previous import of the type `ErrorKind` here
...
20 | io::{Error as IoError, ErrorKind},
| ^^^^^^^^^ `ErrorKind` reimported here
|
= note: `ErrorKind` must be defined only once in the type namespace of this module
error[E0252]: the name `Path` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:21:5
|
14 | path::Path,
| ---------- previous import of the type `Path` here
...
21 | path::Path,
| ^^^^^^^^^^ `Path` reimported here
|
= note: `Path` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
21 | path::Path as OtherPath,
| ~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `File` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:25:5
|
11 | fs::File,
| -------- previous import of the type `File` here
...
25 | fs::File,
| ^^^^^^^^ `File` reimported here
|
= note: `File` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
25 | fs::File as OtherFile,
| ~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `BufReader` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:26:42
|
13 | io::{BufReader, Error as IoError, ErrorKind},
| --------- previous import of the type `BufReader` here
...
26 | io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
| ^^^^^^^^^ `BufReader` reimported here
|
= note: `BufReader` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
26 | io::{AsyncBufReadExt, AsyncWriteExt, BufReader as OtherBufReader},
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `Cursor` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:13:11
|
6 | io::{BufReader, Cursor, Error as IoError, ErrorKind},
| ------ previous import of the type `Cursor` here
...
13 | use std::{io::Cursor, path::Path};
| ^^^^^^^^^^ `Cursor` reimported here
|
= note: `Cursor` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
13 | use std::{io::Cursor as OtherCursor, path::Path};
| ~~~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `Path` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:13:23
|
10 | use async_std::{fs::File, path::Path};
| ---------- previous import of the type `Path` here
...
13 | use std::{io::Cursor, path::Path};
| ^^^^^^^^^^ `Path` reimported here
|
= note: `Path` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
13 | use std::{io::Cursor, path::Path as OtherPath};
| ~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `BufReader` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:16:36
|
6 | io::{BufReader, Cursor, Error as IoError, ErrorKind},
| --------- previous import of the type `BufReader` here
...
16 | AsyncBufReadExt, AsyncReadExt, BufReader, Error as IoError, ErrorKind,
| ^^^^^^^^^ `BufReader` reimported here
|
= note: `BufReader` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
16 | AsyncBufReadExt, AsyncReadExt, BufReader as OtherBufReader, Error as IoError, ErrorKind,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `IoError` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:16:47
|
6 | io::{BufReader, Cursor, Error as IoError, ErrorKind},
| ---------------- previous import of the type `IoError` here
...
16 | AsyncBufReadExt, AsyncReadExt, BufReader, Error as IoError, ErrorKind,
| ^^^^^^^^^^^^^^^^--
| |
| `IoError` reimported here
| help: remove unnecessary import
|
= note: `IoError` must be defined only once in the type namespace of this module
error[E0252]: the name `ErrorKind` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:16:65
|
6 | io::{BufReader, Cursor, Error as IoError, ErrorKind},
| --------- previous import of the type `ErrorKind` here
...
16 | AsyncBufReadExt, AsyncReadExt, BufReader, Error as IoError, ErrorKind,
| ^^^^^^^^^-
| |
| `ErrorKind` reimported here
| help: remove unnecessary import
|
= note: `ErrorKind` must be defined only once in the type namespace of this module
error[E0252]: the name `File` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/config.rs:20:5
|
10 | use async_std::{fs::File, path::Path};
| -------- previous import of the type `File` here
...
20 | use tokio::fs::File;
| ^^^^^^^^^^^^^^^ `File` reimported here
|
= note: `File` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
20 | use tokio::fs::File as OtherFile;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error[E0252]: the name `Path` is defined multiple times
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/model/default_model.rs:20:5
|
17 | use async_std::path::Path;
| --------------------- previous import of the type `Path` here
...
20 | use std::path::Path;
| ^^^^^^^^^^^^^^^ `Path` reimported here
|
= note: `Path` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
|
20 | use std::path::Path as OtherPath;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error[E0599]: no method named `next_line` found for struct `async_std::io::Lines` in the current scope
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:66:38
|
66 | while let Some(line) = lines.next_line().await? {
| ^^^^^^^^^ method not found in `async_std::io::Lines<async_std::io::BufReader<async_std::fs::File>>`
error[E0599]: no method named `next_line` found for struct `async_std::io::Lines` in the current scope
--> /home/siddhesh/.cargo/registry/src/github.com-1ecc6299db9ec823/casbin-2.0.9/src/adapter/file_adapter.rs:91:38
|
91 | while let Some(line) = lines.next_line().await? {
| ^^^^^^^^^ method not found in `async_std::io::Lines<async_std::io::BufReader<async_std::fs::File>>`
Some errors have detailed explanations: E0252, E0599.
For more information about an error, try `rustc --explain E0252`.
error: could not compile `casbin` due to 14 previous errors
After ensuring the build compiles in the individual directories in the casbin-rs/examples, the next task in the line was to ensure that the main workspace compile successfully. From the error console it was not clear what was exactly causing the error. I figured out that the error was due to the simultanous usage of tokio and async-std feature of casbin with the help of tokio community. Initially I tried to enable async-std feature and disable tokio since there was reimport of tokio. But since actix uses tokio, there was still import of the tokio. Hence I had to enable tokio-runtime and disable async-std-runtimes.
Following error was encountered after resolving the above conflict:
actix-casbin had deprecated version of tokio which was causing different versions of tokio and hence had to update it. Opened a PR to do so.
axum-middleware-example
The next task in list was to develop a real-life example using axum-casbin-auth. I had actix-middleware-example developed by Eason Chai for reference. I did some research and found following example good enough to be reproduced in Rust.
Authorization in Golang Projects using Casbin
I will aim to make a example capable of doing simple CRUD operations on backend.
- Backend:
Postgres dieselto access backend.
What will app do: I aim to have a basic application based on RBAC model. I will group users into two groups: doctor and patient. As obvious it sounds, doctor will have priveledged permissions than patient.
The rbac.conf looks like:
[request_definition]
r = sub, obj, act
[policy_definition]
p = sub, obj, act
[role_definition]
g = _, _
[policy_effect]
e = some(where (p.eft == allow))
[matchers]
m = g(r.sub, p.sub) && r.obj == p.obj && r.act == p.act
The application will match the permissions from frontend to backend and will respond with appropriate response. The identification would be done via email and password.
The user model looks like:
#[derive(Debug, Serialize, Deserialize, Queryable)]
#[diesel(table_name = users)]
pub struct User {
pub id: i32,
pub username: String,
pub email: String,
pub password: String,
pub role: String,
}
In this week I aimed at creating a Database, a basic filestructure, and add code templates. Following are few examples:
bcrypt.rs:
use crate::constants;
use bcrypt::{hash, verify, DEFAULT_COST};
use std::env;
pub fn hash_password() {}
pub fn compare_password() {}
pub fn generate_token() {}
pub fn validate_token() {}
auth.rs:
impl<S, ReqBody, ResBody> Service<Request<ReqBody>> for AuthMiddleware<S>
where
S: Service<Request<ReqBody>, Response = Response<ResBody>, Error = Infallible>
+ Clone
+ Send
+ 'static,
S::Future: Send + 'static,
ReqBody: Send + 'static,
Infallible: From<<S as Service<Request<ReqBody>>>::Error>,
ResBody: HttpBody<Data = Bytes> + Send + 'static,
ResBody::Error: Into<BoxError>,
{
type Response = S::Response;
type Error = S::Error;
// `BoxFuture` is a type alias for `Pin<Box<dyn Future + Send + 'a>>`
type Future = BoxFuture<'static, Result<Self::Response, Self::Error>>;
fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
self.inner.poll_ready(cx)
}
fn call(&mut self, mut req: Request<ReqBody>) -> Self::Future {
let not_ready_inner = self.inner.clone();
let mut inner = std::mem::replace(&mut self.inner, not_ready_inner);
// IMPLEMENT LOGIC HERE
Box::pin(async move {
inner.call(req).await
})
}
}
After setting up the user model run the diesel migration generate users command to generate the migrations file for our database. Setup the database structure:
CREATE TABLE users
(
id SERIAL PRIMARY KEY,
username VARCHAR(32) NOT NULL,
email VARCHAR(100) NOT NULL,
password VARCHAR(200) NOT NULL,
role VARCHAR(32) NOT NULL
);
INSERT INTO users
VALUES (0, 'John', 'john@john.com', 'imjohn', 'doctor');
INSERT INTO users
VALUES (1, 'Sam', 'sam@sam.com', 'imsam', 'patient');
diesel migration run to generate the schema.rs file:
table! {
users (id) {
id -> Int4,
username -> Varchar,
email -> Varchar,
password -> Varchar,
role -> Varchar,
}
}
Next we will connect database with out project, for this add following .env file:
APP_HOST=127.0.0.1
APP_PORT=8080
DATABASE_URL=postgres://postgres:postgresAdmin@127.0.0.1:5432/casbintest
POOL_SIZE=8
HASH_ROUNDS=12
Connect database with project:
fn establish_connection() -> PgConnection {
dotenv().ok();
let database_url = env::var("DATABASE_URL").expect("DATABASE_URL must be set");
PgConnection::establish(&database_url)
.expect(&format!("Error connecting to {}", database_url))
}
Now load the data from the project to database. Will do this in main.rs. After successful setup of the database, we get the following output:
1644 Words
2022-07-15 22:43