Write the build start to the database.

src/nix_util/running_build.rs

@@ -1,3 +1,4 @@
+use sqlx::Row;
 use tokio::io::AsyncBufReadExt;
 use tokio::io::BufReader;
 use tokio::io::Lines;
@@ -17,7 +18,22 @@ impl<'db> RunningBuild<'db> {
         Ok(RunningBuild { db_handle })
     }
 
-    pub(crate) async fn run_to_completion(&mut self, mut child: Child) -> Result<()> {
+    pub(crate) async fn run_to_completion<TN>(
+        &mut self,
+        mut child: Child,
+        target_name: TN,
+    ) -> Result<()>
+    where
+        TN: AsRef<str>,
+    {
+        let build_id: i64 = sqlx::query(
+            r#"INSERT INTO build (start_time, target) SELECT unixepoch('now'), ? RETURNING id"#,
+        )
+        .bind(target_name.as_ref())
+        .fetch_one(&self.db_handle.conn)
+        .await?
+        .try_get("id")?;
+
         let mut output_stream = OutputStream::from_child(&mut child)?;
 
         let exit_status_handle = tokio::spawn(async move {
@@ -41,6 +57,19 @@ impl<'db> RunningBuild<'db> {
         let exit_status = exit_status_handle.await?;
         println!("nixos-rebuild status was: {}", exit_status);
 
+        let update: u64 =
+            sqlx::query(r#"UPDATE build SET end_time=unixepoch('now'), status=? WHERE id=?"#)
+                .bind(
+                    exit_status
+                        .code()
+                        .expect("Process should have an exit code."),
+                )
+                .bind(build_id)
+                .execute(&self.db_handle.conn)
+                .await?
+                .rows_affected();
+        assert!(update == 1);
+
         Ok(())
     }