add Map::clear() to db interface

Signed-off-by: Jason Volk <jason@zemos.net>

src/database/map.rs

@@ -1,3 +1,4 @@
+mod clear;
 pub mod compact;
 mod contains;
 mod count;

src/database/map/clear.rs

@@ -0,0 +1,30 @@
+use std::sync::Arc;
+
+use conduwuit::{
+	Result, implement,
+	utils::stream::{ReadyExt, TryIgnore},
+};
+use futures::{Stream, TryStreamExt};
+
+use crate::keyval::Key;
+
+/// Delete all data stored in this map. !!! USE WITH CAUTION !!!
+///
+/// See for_clear() with additional details.
+#[implement(super::Map)]
+#[tracing::instrument(level = "trace")]
+pub async fn clear(self: &Arc<Self>) {
+	self.for_clear().ignore_err().ready_for_each(|_| ()).await;
+}
+
+/// Delete all data stored in this map. !!! USE WITH CAUTION !!!
+///
+/// Provides stream of keys undergoing deletion along with any errors.
+///
+/// Note this operation applies to a snapshot of the data when invoked.
+/// Additional data written during or after this call may be missed.
+#[implement(super::Map)]
+#[tracing::instrument(level = "trace")]
+pub fn for_clear(self: &Arc<Self>) -> impl Stream<Item = Result<Key<'_>>> + Send {
+	self.raw_keys().inspect_ok(|key| self.remove(key))
+}