Chapter 06 - Building db connection pool section

[ssjsk]

Hi,
has anyone managed to run chapter06/building_a_database_connection_pool codebase locally? I'm stuck with compile time errors, seems connections are expected to be mutable, but at time of this repo creation it wasn't the case. I tried to change get_state to following, along with create/edit/delete rs file but with that I get trait not implemented error "the trait bound &mut DB: FromRequest is not satisfied" because its immutable DB
I'm using Rust 1.83 on ubuntu 24.

pub fn get_state(db: &mut DB) -> ToDoItems {
        let connection = &mut db.connection;
        //let mut connection: diesel::PgConnection = _establish_connection();
        let mut array_buffer = Vec::new();
        let items = to_do::table
            .order_by(to_do::columns::id.asc())
            .load::<Item>(connection)
            .unwrap();

        for item in items {
            let status = TaskStatus::from_string(item.status.as_str().to_string());
            let item = to_do_factory(&item.title, status);
            array_buffer.push(item);
        }
        return ToDoItems::new(array_buffer);
    }

[xenospathos]

Hi @ssjsk,

Not sure if you have moved past this yet - in the later code that I am working on this is running fine:

 pub fn get_state(user_id: i32) -> ToDoItems {
        let connection = DBCONNECTION.db_connection.get().unwrap();

        let items = to_do::table
            .filter(to_do::columns::user_id.eq(&user_id))
            .order(to_do::columns::id.asc())
            .load::<Item>(&connection).unwrap();
        
        let mut array_buffer = Vec::with_capacity(items.len());

        for item in items {
            let status = TaskStatus::from_string(item.status.as_str().to_string());
            let item = to_do_factory(&item.title, status);
            array_buffer.push(item);
        }

        return ToDoItems::new(array_buffer)}

I believe that where you are you should be able to do this with:

use crate::database::DBCONNECTION;

{...}

    pub fn get_state() -> ToDoItems {
        let connection = DBCONNECTION.db_connection.get().unwrap();

        let items = to_do::table
            .order(to_do::columns::id.asc())
            .load::<Item>(&connection).unwrap();
        
        let mut array_buffer = Vec::with_capacity(items.len());

        for item in items {
            let status = TaskStatus::from_string(item.status.as_str().to_string());
            let item = to_do_factory(&item.title, status);
            array_buffer.push(item);
        }

        return ToDoItems::new(array_buffer)
    }