Replace ORM with plain SQL

Also move DB stuff into module.

Cargo.toml

@@ -11,5 +11,7 @@ axum = "0.7"
 askama = "0.12"
 askama_axum = "0.4"
 tower-http = { version = "0.5", features = ["fs"] }
-diesel = { version = "2.1", features = ["postgres", "chrono"] }
-deadpool-diesel = {version = "0.5", features = ["postgres"]}
+r2d2_postgres = "0.18"
+deadpool-r2d2 = {version = "0.3", features = ["rt_tokio_1"]}
+deadpool = "0.10"
+thiserror = "1.0"

diesel.toml

@@ -1,9 +0,0 @@
-# For documentation on how to configure this file,
-# see https://diesel.rs/guides/configuring-diesel-cli
-
-[print_schema]
-file = "src/schema.rs"
-custom_type_derives = ["diesel::query_builder::QueryId"]
-
-[migrations_directory]
-dir = "migrations"

migrations/00000000000000_diesel_initial_setup/down.sql

@@ -1,6 +0,0 @@
--- This file was automatically created by Diesel to setup helper functions
--- and other internal bookkeeping. This file is safe to edit, any future
--- changes will be added to existing projects as new migrations.
-
-DROP FUNCTION IF EXISTS diesel_manage_updated_at(_tbl regclass);
-DROP FUNCTION IF EXISTS diesel_set_updated_at();

migrations/00000000000000_diesel_initial_setup/up.sql

@@ -1,36 +0,0 @@
--- This file was automatically created by Diesel to setup helper functions
--- and other internal bookkeeping. This file is safe to edit, any future
--- changes will be added to existing projects as new migrations.
-
-
-
-
--- Sets up a trigger for the given table to automatically set a column called
--- `updated_at` whenever the row is modified (unless `updated_at` was included
--- in the modified columns)
---
--- # Example
---
--- ```sql
--- CREATE TABLE users (id SERIAL PRIMARY KEY, updated_at TIMESTAMP NOT NULL DEFAULT NOW());
---
--- SELECT diesel_manage_updated_at('users');
--- ```
-CREATE OR REPLACE FUNCTION diesel_manage_updated_at(_tbl regclass) RETURNS VOID AS $$
-BEGIN
-    EXECUTE format('CREATE TRIGGER set_updated_at BEFORE UPDATE ON %s
-                    FOR EACH ROW EXECUTE PROCEDURE diesel_set_updated_at()', _tbl);
-END;
-$$ LANGUAGE plpgsql;
-
-CREATE OR REPLACE FUNCTION diesel_set_updated_at() RETURNS trigger AS $$
-BEGIN
-    IF (
-        NEW IS DISTINCT FROM OLD AND
-        NEW.updated_at IS NOT DISTINCT FROM OLD.updated_at
-    ) THEN
-        NEW.updated_at := current_timestamp;
-    END IF;
-    RETURN NEW;
-END;
-$$ LANGUAGE plpgsql;

migrations/2024-02-11-020849_create_users/down.sql

@@ -1 +0,0 @@
-DROP TABLE users;

migrations/2024-02-11-020849_create_users/up.sql

@@ -1,8 +0,0 @@
-CREATE TABLE users (
-  id SERIAL PRIMARY KEY,
-  username VARCHAR NOT NULL,
-  real_name VARCHAR NOT NULL,
-  email VARCHAR NOT NULL,
-  password_hash VARCHAR NOT NULL,
-  password_salt VARCHAR NOT NULL
-);

src/db.rs

@@ -0,0 +1,47 @@
+use {
+    deadpool, deadpool_r2d2::Runtime, thiserror::Error,
+};
+
+type PgManager = deadpool_r2d2::Manager<
+    r2d2_postgres::PostgresConnectionManager<r2d2_postgres::postgres::NoTls>,
+>;
+type PgPool = deadpool_r2d2::Pool<PgManager>;
+
+#[derive(Error, Debug)]
+pub enum Error {
+    #[error("Could not initialize DB connection pool.")]
+    ConnectionPoolError(#[from] deadpool::managed::BuildError),
+    #[error("Error with Postgres database")]
+    PostrgesError(#[from] r2d2_postgres::postgres::Error)
+}
+
+#[derive(Clone)]
+pub struct Database {
+    pg_pool: PgPool,
+}
+
+impl Database {
+    pub fn create_pool(connection_url: &str, max_size: usize) -> Result<Database, Error> {
+        let pg_config: r2d2_postgres::postgres::Config = connection_url.parse()?;
+        let r2d2_manager = r2d2_postgres::PostgresConnectionManager::new(
+            pg_config,
+            r2d2_postgres::postgres::NoTls,
+        );
+        let manager = PgManager::new(r2d2_manager, Runtime::Tokio1);
+        let pg_pool = PgPool::builder(manager).max_size(max_size).build()?;
+        Ok(Database { pg_pool })
+    }
+
+    pub async fn log_num_users(&self) -> usize {
+        self.pg_pool
+            .get()
+            .await
+            .unwrap()
+            .interact(|conn| {
+                let results = conn.query("SELECT * FROM users;", &[]).unwrap();
+                results.len()
+            })
+            .await
+            .unwrap()
+    }
+}

src/main.rs

@@ -1,19 +1,16 @@
 use {
     askama::Template,
     axum::{extract::State, routing::get, Router},
-    deadpool_diesel::postgres::{Manager, Pool, Runtime},
     std::env,
     tower_http::services::ServeDir,
 };
 
-mod models;
-mod schema;
-
+mod db;
+use db::Database;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let db_pool_manager = Manager::new(env::var("LOCALHUB_DATABASE_URL")?, Runtime::Tokio1);
-    let db_pool = Pool::builder(db_pool_manager).max_size(8).build()?;
+    let db_pool = Database::create_pool(&env::var("LOCALHUB_DATABASE_URL")?, 2)?;
 
     let app = Router::new()
         .route("/", get(root))
@@ -34,13 +31,7 @@ struct IndexTemplate<'a> {
     title: &'a str,
 }
 
-async fn root<'a>(State(db_pool): State<Pool>) -> IndexTemplate<'a> {
-    use self::models::*;
-    use diesel::prelude::*;
-    let db_conn = db_pool.get().await.unwrap();
-    db_conn.interact(|conn| {
-        let results = schema::users::table.select(User::as_select()).load(conn).unwrap();
-        println!("Found {} users", results.len());
-    }).await.unwrap();
+async fn root<'a>(State(database): State<Database>) -> IndexTemplate<'a> {
+    println!("Found {} users", database.log_num_users().await);
     IndexTemplate { title: "LocalHub" }
 }

src/models.rs

@@ -1,13 +0,0 @@
-use diesel::prelude::*;
-
-#[derive(Queryable, Selectable)]
-#[diesel(table_name = crate::schema::users)]
-#[diesel(check_for_backend(diesel::pg::Pg))]
-pub struct User {
-    pub id: i32,
-    pub username: String,
-    pub real_name: String,
-    pub email: String,
-    pub password_hash: String,
-    pub password_salt: String,
-}

src/schema.rs

@@ -1,12 +0,0 @@
-// @generated automatically by Diesel CLI.
-
-diesel::table! {
-    users (id) {
-        id -> Int4,
-        username -> Varchar,
-        real_name -> Varchar,
-        email -> Varchar,
-        password_hash -> Varchar,
-        password_salt -> Varchar,
-    }
-}