make database backends generic

6 files changed, 50 insertions, 14 deletions

diff --git a/src/bin/tosin-admin.rs b/src/bin/tosin-admin.rs
index 6408337..e519d50 100644
--- a/src/bin/tosin-admin.rs
+++ b/src/bin/tosin-admin.rs
@@ -10,6 +10,7 @@ const TOSIN_DEPENDENCY: &str = concat!(r#"tosin = { path = ""#, env!("CARGO_MANI
 const PROJECT_MAIN: &str = r#"
 use tosin::Settings;
 use tosin::contrib::admin;
+use tosin::db::backend::Connectable;
 use tosin::urls::{UrlMap, url_map};
 
 fn urls() -> UrlMap {
@@ -18,7 +19,7 @@ fn urls() -> UrlMap {
     }
 }
 
-fn settings() -> Settings {
+fn settings() -> Settings<impl Connectable> {
     Settings {
         ..Settings::default()
     }
diff --git a/src/cli/migrate.rs b/src/cli/migrate.rs
new file mode 100644
index 0000000..4b5123a
--- /dev/null
+++ b/src/cli/migrate.rs
@@ -0,0 +1,19 @@
+use structopt::StructOpt;
+
+use crate::{Settings, UrlMap, db::backend::{Connectable, Connection}};
+
+#[derive(StructOpt)]
+/// Perform database migrations
+pub struct Migrate {
+}
+
+impl Migrate {
+    pub fn execute(self, _urls: UrlMap, settings: Settings<impl Connectable>) {
+        let database = settings.database;
+        let connection = database.connect().unwrap();
+
+        let migration_table_vibe_check = connection.transaction::<(), diesel::result::Error, _>(|| {
+            todo!()
+        });
+    }
+}
diff --git a/src/cli/mod.rs b/src/cli/mod.rs
index c656c1c..a11fd48 100644
--- a/src/cli/mod.rs
+++ b/src/cli/mod.rs
@@ -1,23 +1,26 @@
 use structopt::StructOpt;
 
-use crate::{Settings, UrlMap};
+use crate::{Settings, UrlMap, db::backend::Connectable};
 
+mod migrate;
 mod run_server;
 
 #[derive(StructOpt)]
 enum Command {
+    Migrate(migrate::Migrate),
     RunServer(run_server::RunServer),
 }
 
 impl Command {
-    fn execute(self, urls: UrlMap, settings: Settings) {
+    fn execute(self, urls: UrlMap, settings: Settings<impl Connectable>) {
         match self {
+            Command::Migrate(command) => command.execute(urls, settings),
             Command::RunServer(command) => command.execute(urls, settings),
         }
     }
 }
 
-pub fn main(urls: UrlMap, settings: Settings) {
+pub fn main(urls: UrlMap, settings: Settings<impl Connectable>) {
     let command = Command::from_args();
     command.execute(urls, settings);
 }
diff --git a/src/cli/run_server.rs b/src/cli/run_server.rs
index 242c824..66e6fe1 100644
--- a/src/cli/run_server.rs
+++ b/src/cli/run_server.rs
@@ -1,6 +1,6 @@
 use structopt::StructOpt;
 
-use crate::{Settings, UrlMap};
+use crate::{Settings, UrlMap, db::backend::Connectable};
 
 #[derive(StructOpt)]
 /// Run an HTTP server
@@ -11,7 +11,7 @@ pub struct RunServer {
 }
 
 impl RunServer {
-    pub fn execute(self, urls: UrlMap, _settings: Settings) {
+    pub fn execute(self, urls: UrlMap, _settings: Settings<impl Connectable>) {
         println!("Starting server at http://127.0.0.1:{}/", self.port);
         let server_task = warp::serve(urls).run(([127, 0, 0, 1], self.port));
 
diff --git a/src/db/backend.rs b/src/db/backend.rs
index 5ae4de2..b75d5ca 100644
--- a/src/db/backend.rs
+++ b/src/db/backend.rs
@@ -1,5 +1,18 @@
-pub enum DbBackend {
-    Sqlite {
-        db_file: &'static str,
+pub use diesel::connection::Connection;
+
+pub trait Connectable {
+    type Connection: Connection;
+    fn connect(&self) -> diesel::ConnectionResult<Self::Connection>;
+}
+
+pub struct Sqlite {
+    pub db_file: &'static str,
+}
+
+impl Connectable for Sqlite {
+    type Connection = diesel::sqlite::SqliteConnection;
+
+    fn connect(&self) -> diesel::ConnectionResult<Self::Connection> {
+        Self::Connection::establish(self.db_file)
     }
 }
diff --git a/src/settings.rs b/src/settings.rs
index 37a3395..4b140a6 100644
--- a/src/settings.rs
+++ b/src/settings.rs
@@ -1,15 +1,15 @@
-use crate::db::backend::DbBackend;
+use crate::db::backend::{self, Connectable};
 
-pub struct Settings {
+pub struct Settings<C: Connectable> {
     pub installed_apps: &'static [&'static crate::apps::AppConfig],
-    pub database: DbBackend,
+    pub database: C,
 }
 
-impl Default for Settings {
+impl Default for Settings<backend::Sqlite> {
     fn default() -> Self {
         Self {
             installed_apps: &[],
-            database: DbBackend::Sqlite {
+            database: backend::Sqlite {
                 db_file: "db.sqlite3",
             },
         }