Diesel print-schema doesn't generate joinable! for foreign keys (postgresql)

I have two tables with a many-to-many relationship that I would like to do joins on. One table stores users, and the other stores cameras. The many-to-many table is used to store what cameras a user has access to. Multiple users can have access to a camera, hence the need for the many-to-many table. Here's the schema:

CREATE TABLE cameras (
    camera_id uuid PRIMARY KEY DEFAULT uuid_generate_v4() NOT NULL UNIQUE,
    name text NOT NULL
);

CREATE TABLE users (
    user_id uuid PRIMARY KEY DEFAULT uuid_generate_v4() NOT NULL UNIQUE,
    username text NOT NULL UNIQUE,
    password text NOT NULL
);

And this is the many-to-many table linking these two:

CREATE TABLE users_cameras (
    users_cameras_id SERIAL PRIMARY KEY,
    camera_id uuid NOT NULL,
    user_id uuid NOT NULL,
    CONSTRAINT fk_camera_id
        FOREIGN KEY (camera_id)
            REFERENCES cameras (camera_id)
            ON DELETE CASCADE,
    CONSTRAINT fk_user_id
        FOREIGN KEY (user_id)
            REFERENCES users (user_id)
            ON DELETE CASCADE
);

When I run diesel print-schema, this is the output:

table! {
    cameras (camera_id) {
        camera_id -> Uuid,
        name -> Text,
    }
}

table! {
    users (user_id) {
        user_id -> Uuid,
        username -> Text,
        password -> Text,
    }
}

table! {
    users_cameras (users_cameras_id) {
        users_cameras_id -> Int4,
        camera_id -> Uuid,
        user_id -> Uuid,
    }
}

allow_tables_to_appear_in_same_query!(
    cameras,
    users,
    users_cameras,
);

This doesn't generate the joinable! stuff, meaning that I can't perform joins for these tables. Am I laying out my data wrong, or is this a limitation of diesel?