chore: set up skeleton project

src/db/mod.rs

@@ -0,0 +1,62 @@
+mod models;
+mod schema;
+
+use diesel::{
+    r2d2::{ConnectionManager, Pool},
+    SqliteConnection,
+};
+use diesel_migrations::{embed_migrations, EmbeddedMigrations, MigrationHarness};
+
+use std::{error::Error, fmt, path::Path};
+
+pub const MIGRATIONS: EmbeddedMigrations = embed_migrations!("migrations");
+
+pub type DbPool = Pool<ConnectionManager<SqliteConnection>>;
+pub type DbResult<T> = Result<T, DbError>;
+
+#[derive(Debug)]
+pub enum DbError {
+    Pool(diesel::r2d2::PoolError),
+    Db(diesel::result::Error),
+}
+
+impl fmt::Display for DbError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Pool(_) => write!(f, "failed to acquire connection from pool"),
+            Self::Db(_) => write!(f, "error while executing query"),
+        }
+    }
+}
+
+impl Error for DbError {
+    fn source(&self) -> Option<&(dyn Error + 'static)> {
+        match self {
+            Self::Pool(err) => Some(err),
+            Self::Db(err) => Some(err),
+        }
+    }
+}
+
+impl From<diesel::r2d2::PoolError> for DbError {
+    fn from(value: diesel::r2d2::PoolError) -> Self {
+        Self::Pool(value)
+    }
+}
+
+impl From<diesel::result::Error> for DbError {
+    fn from(value: diesel::result::Error) -> Self {
+        Self::Db(value)
+    }
+}
+
+pub fn initialize_db(path: impl AsRef<Path>, run_migrations: bool) -> Result<DbPool, DbError> {
+    let manager = ConnectionManager::<SqliteConnection>::new(path.as_ref().to_string_lossy());
+    let pool = Pool::new(manager)?;
+
+    if run_migrations {
+        pool.get()?.run_pending_migrations(MIGRATIONS).unwrap();
+    }
+
+    Ok(pool)
+}

src/db/schema.rs

@@ -0,0 +1,2 @@
+// @generated automatically by Diesel CLI.
+