feat: migration and project structure

Cargo.toml

@@ -7,4 +7,11 @@ license = "MIT"
 
 [dependencies]
 rocket = "0.3.16"
-rocket_codegen = "0.3.16"
+rocket_codegen = "0.3.16"
+rocket_contrib = "0.3"
+diesel = { version = "1.0.0", features = ["postgres", "r2d2"] }
+dotenv = "0.9.0"
+r2d2 = "0.8"
+lazy_static = "1.1"
+serde = "1.0"
+serde_derive = "1.0"

Rocket.toml

@@ -1,5 +1,2 @@
 [global]
-template_dir = "static"
-
-[global.databases.sqlite_database]
-url = "db/db.sqlite"
+template_dir = "static"

migrations/00000000000000_diesel_initial_setup/down.sql

@@ -0,0 +1,6 @@
+-- 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

@@ -0,0 +1,36 @@
+-- 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/2018-09-13-162215_create_posts/down.sql

@@ -0,0 +1,2 @@
+-- This file should undo anything in `up.sql`
+DROP TABLE posts

migrations/2018-09-13-162215_create_posts/up.sql

@@ -0,0 +1,7 @@
+-- Your SQL goes here
+CREATE TABLE posts (
+  id SERIAL PRIMARY KEY,
+  title VARCHAR NOT NULL,
+  body TEXT NOT NULL,
+  published BOOLEAN NOT NULL DEFAULT 'f'
+)

src/main.rs

@@ -1,6 +1,20 @@
 #![feature(plugin)]
 #![plugin(rocket_codegen)]
 extern crate rocket;
+extern crate diesel;
+extern crate dotenv;
+extern crate r2d2;
+
+#[macro_use]
+extern crate rocket_contrib;
+
+#[macro_use]
+extern crate serde_derive;
+
+mod pg_pool;
+mod schema;
+use dotenv::dotenv;
+
 
 #[get("/")]
 fn index() -> String {
@@ -8,5 +22,11 @@ fn index() -> String {
 }
 
 fn main() {
-    rocket::ignite().mount("/",routes![index]).launch();
+    dotenv().ok();
+    let database_url = std::env::var("database_url").expect("database_url must be set");
+
+    rocket::ignite()
+        .manage(pg_pool::init(&database_url))
+        .mount("/",routes![index])
+        .launch();
 }

src/pg_pool.rs

@@ -0,0 +1,42 @@
+use diesel::pg::PgConnection;
+use r2d2;
+use diesel::r2d2::ConnectionManager;
+
+type ManagedPgConn = ConnectionManager<PgConnection>;
+type Pool = r2d2::Pool<ManagedPgConn>;
+
+use rocket::http::Status;
+use rocket::request::{self, FromRequest};
+use rocket::{Outcome, Request, State};
+use std::ops::Deref;
+/// Db Connection request guard type: wrapper around r2d2 pooled connection
+pub struct DbConn(pub r2d2::PooledConnection<ManagedPgConn>);
+
+/// Attempts to retrieve a single connection from the managed database pool. If
+/// no pool is currently managed, fails with an `InternalServerError` status. If
+/// no connections are available, fails with a `ServiceUnavailable` status.
+impl<'a, 'r> FromRequest<'a, 'r> for DbConn {
+    type Error = ();
+
+    fn from_request(request: &'a Request<'r>) -> request::Outcome<DbConn, ()> {
+        let pool = request.guard::<State<Pool>>()?;
+        match pool.get() {
+            Ok(conn) => Outcome::Success(DbConn(conn)),
+            Err(_) => Outcome::Failure((Status::ServiceUnavailable, ())),
+        }
+    }
+}
+
+// For the convenience of using an &DbConn as an &SqliteConnection.
+impl Deref for DbConn {
+    type Target = PgConnection;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+pub fn init(database_url: &str) -> Pool {
+    let manager = ConnectionManager::<PgConnection>::new(database_url);
+    r2d2::Pool::new(manager).expect("Failed to create pool.")
+}

src/schema.rs

@@ -0,0 +1,8 @@
+table! {
+    posts (id) {
+        id -> Int4,
+        title -> Varchar,
+        body -> Text,
+        published -> Bool,
+    }
+}