db: add sqlite query tracing during tests

database/src/sqlite.rs

@@ -42,13 +42,42 @@ impl Sqlite {
         Self::new_internal(base_dir, manager)
     }
 
+    #[cfg(test)]
+    fn build_pool(manager: SqliteConnectionManager) -> Result<r2d2::Pool<SqliteConnectionManager>> {
+        #[derive(Copy, Clone, Debug)]
+        pub struct LogConnectionCustomizer;
+        impl<E> r2d2::CustomizeConnection<rusqlite::Connection, E> for LogConnectionCustomizer {
+            fn on_acquire(&self, conn: &mut rusqlite::Connection) -> std::result::Result<(), E> {
+                println!("Acquiring sqlite pool connection: {:?}", conn);
+                conn.trace(Some(|query| {
+                    println!("{}", query);
+                }));
+                std::result::Result::Ok(())
+            }
+
+            fn on_release(&self, conn: rusqlite::Connection) {
+                println!("Releasing pool connection: {:?}", conn);
+            }
+        }
+
+        Ok(r2d2::Pool::builder()
+            .max_size(2)
+            .connection_customizer(Box::new(LogConnectionCustomizer {}))
+            .build(manager)?)
+    }
+
+    #[cfg(not(test))]
+    fn build_pool(manager: SqliteConnectionManager) -> Result<r2d2::Pool<SqliteConnectionManager>> {
+        Ok(r2d2::Pool::builder().build(manager)?)
+    }
+
     fn new_internal(base_dir: PathBuf, manager: SqliteConnectionManager) -> Result<Self> {
         let keys_dir_log = base_dir.join("log");
         create_dir_all(&keys_dir_log)?;
 
         let dry_run = false;
 
-        let pool = r2d2::Pool::builder().max_size(2).build(manager)?;
+        let pool = Self::build_pool(manager)?;
         let conn = pool.get()?;
         conn.execute(
             "CREATE TABLE IF NOT EXISTS certs (