Move crates to toplevel directory

database/src/error.rs

@@ -0,0 +1,24 @@
+/// Error that happens within the database module.
+#[derive(thiserror::Error, Debug)]
+pub enum Error {
+    #[error(transparent)]
+    ConnectionError(#[from] diesel::result::ConnectionError),
+
+    #[error(transparent)]
+    MigrationsError(#[from] diesel_migrations::RunMigrationsError),
+
+    #[error(transparent)]
+    QueryError(#[from] diesel::result::Error),
+
+    #[error(transparent)]
+    SendError(#[from] std::sync::mpsc::SendError<super::thread::Action>),
+
+    #[error(transparent)]
+    ReceiveError(#[from] futures_channel::oneshot::Canceled),
+
+    #[error("Database error: {0}")]
+    Other(String),
+}
+
+/// Return type for database methods.
+pub type Result<T> = std::result::Result<T, Error>;