Add clear command

Signed-off-by: trivernis <trivernis@protonmail.com>

src/commands/misc/clear.rs

@@ -0,0 +1,38 @@
+use bot_serenityutils::core::SHORT_TIMEOUT;
+use bot_serenityutils::ephemeral_message::EphemeralMessage;
+use futures::future::BoxFuture;
+use serenity::client::Context;
+use serenity::framework::standard::macros::command;
+use serenity::framework::standard::{Args, CommandResult};
+use serenity::model::channel::Message;
+use serenity::Result as SerenityResult;
+
+#[command]
+#[description("Clears the chat (maximum 100 messages)")]
+#[usage("[<number>]")]
+#[example("20")]
+#[min_args(0)]
+#[max_args(1)]
+#[bucket("general")]
+#[required_permissions("MANAGE_MESSAGES")]
+async fn clear(ctx: &Context, msg: &Message, mut args: Args) -> CommandResult {
+    let limit = args.single::<u64>().unwrap_or(20);
+    log::debug!("Deleting messages for channel {}", msg.channel_id);
+    let messages = msg.channel_id.messages(ctx, |b| b.limit(limit)).await?;
+    log::debug!("Deleting {} messages", messages.len());
+    let futures: Vec<BoxFuture<SerenityResult<()>>> = messages
+        .into_iter()
+        .map(|m| async move { ctx.http.delete_message(m.channel_id.0, m.id.0).await }.boxed())
+        .collect();
+    log::debug!("Waiting for all messages to be deleted");
+    let deleted = futures::future::join_all(futures).await;
+    let deleted_count = deleted.into_iter().filter(|d| d.is_ok()).count();
+    log::debug!("{} Messages deleted", deleted_count);
+
+    EphemeralMessage::create(&ctx.http, msg.channel_id, SHORT_TIMEOUT, |f| {
+        f.content(format!("Deleted {} messages", deleted_count))
+    })
+    .await?;
+
+    Ok(())
+}

src/commands/misc/mod.rs

@@ -2,6 +2,7 @@ use serenity::framework::standard::macros::group;
 
 use about::ABOUT_COMMAND;
 use add_gif::ADD_GIF_COMMAND;
+use clear::CLEAR_COMMAND;
 use gifs::GIFS_COMMAND;
 use pain::PAIN_COMMAND;
 use ping::PING_COMMAND;
@@ -13,6 +14,7 @@ use timezones::TIMEZONES_COMMAND;
 
 mod about;
 mod add_gif;
+mod clear;
 mod gifs;
 pub(crate) mod help;
 mod pain;
@@ -25,6 +27,6 @@ mod timezones;
 
 #[group]
 #[commands(
-    ping, stats, shutdown, time, timezones, qalc, about, add_gif, gifs, pain
+    ping, stats, shutdown, time, timezones, qalc, about, add_gif, gifs, pain, clear
 )]
 pub struct Misc;