remove reactions from messages older than n days

.env.template

@@ -0,0 +1,9 @@
+DISCORD_BOT_TOKEN=
+DISCORD_DAYS_TO_DELETE_REACTION=
+DISCORD_LOG_CHANNEL_ID=
+DISCORD_WELCOME_CHANNEL_ID=
+
+BOT_REDIS_URL="redis://localhost:6379"
+
+RUST_LOG="refraction=debug"
+RUST_BACKTRACE=1

.gitignore

@@ -17,7 +17,7 @@ Cargo.lock
 # direnv secrets
 .env
 .env.*
-!.env.example
+!.env.template
 
 # Nix
 .direnv/

Cargo.lock

@@ -241,15 +241,17 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "chrono"
-version = "0.4.31"
+version = "0.4.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f2c685bad3eb3d45a01354cedb7d5faa66194d1d58ba6e267a8de788f79db38"
+checksum = "8a0d04d43504c61aa6c7531f1871dd0d418d91130162063b789da00fd7057a5e"
 dependencies = [
  "android-tzdata",
  "iana-time-zone",
+ "js-sys",
  "num-traits",
  "serde",
- "windows-targets 0.48.5",
+ "wasm-bindgen",
+ "windows-targets 0.52.0",
 ]
 
 [[package]]
@@ -1445,6 +1447,7 @@ dependencies = [
 name = "refraction"
 version = "2.0.0"
 dependencies = [
+ "chrono",
  "color-eyre",
  "dotenvy",
  "enum_dispatch",

Cargo.toml

@@ -15,6 +15,7 @@ serde = "1.0.196"
 serde_json = "1.0.112"
 
 [dependencies]
+chrono = "0.4.37"
 color-eyre = "0.6.2"
 dotenvy = "0.15.7"
 enum_dispatch = "0.3.12"

src/config/discord.rs

@@ -1,5 +1,6 @@
 use std::str::FromStr;
 
+use eyre::{Context, Result};
 use log::{info, warn};
 use poise::serenity_prelude::ChannelId;
 
@@ -12,6 +13,7 @@ pub struct RefractionChannels {
 #[derive(Clone, Debug, Default)]
 pub struct Config {
 	pub channels: RefractionChannels,
+	pub days_to_delete_reaction: i64,
 }
 
 impl RefractionChannels {
@@ -22,15 +24,15 @@ impl RefractionChannels {
 		}
 	}
 
-	pub fn new_from_env() -> Self {
-		let log_channel_id = Self::get_channel_from_env("DISCORD_LOG_CHANNEL_ID");
+	pub fn from_env() -> Self {
+		let log_channel_id = Self::channel_from_env("DISCORD_LOG_CHANNEL_ID");
 		if let Some(channel_id) = log_channel_id {
 			info!("Log channel is {channel_id}");
 		} else {
 			warn!("DISCORD_LOG_CHANNEL_ID is empty; this will disable logging in your server.");
 		}
 
-		let welcome_channel_id = Self::get_channel_from_env("DISCORD_WELCOME_CHANNEL_ID");
+		let welcome_channel_id = Self::channel_from_env("DISCORD_WELCOME_CHANNEL_ID");
 		if let Some(channel_id) = welcome_channel_id {
 			info!("Welcome channel is {channel_id}");
 		} else {
@@ -40,7 +42,7 @@ impl RefractionChannels {
 		Self::new(log_channel_id, welcome_channel_id)
 	}
 
-	fn get_channel_from_env(var: &str) -> Option<ChannelId> {
+	fn channel_from_env(var: &str) -> Option<ChannelId> {
 		std::env::var(var)
 			.ok()
 			.and_then(|env_var| ChannelId::from_str(&env_var).ok())
@@ -48,13 +50,22 @@ impl RefractionChannels {
 }
 
 impl Config {
-	pub fn new(channels: RefractionChannels) -> Self {
-		Self { channels }
+	pub fn new(channels: RefractionChannels, days_to_delete_reaction: i64) -> Self {
+		Self {
+			channels,
+			days_to_delete_reaction,
+		}
 	}
 
-	pub fn from_env() -> Self {
-		let channels = RefractionChannels::new_from_env();
+	pub fn from_env() -> Result<Self> {
+		let channels = RefractionChannels::from_env();
+		let days_to_delete_reaction = std::env::var("DISCORD_DAYS_TO_DELETE_REACTION")
+			.wrap_err("DISCORD_DAYS_TO_DELETE_REACTION is empty! This variable is required.")?
+			.parse()
+			.wrap_err("DISCORD_DAYS_TO_DELETE_REACTION is not a number!")?;
 
-		Self::new(channels)
+		info!("Reactions will be deleted on messages older than {days_to_delete_reaction} days");
+
+		Ok(Self::new(channels, days_to_delete_reaction))
 	}
 }

src/config/mod.rs

@@ -1,3 +1,5 @@
+use eyre::Result;
+
 mod bot;
 mod discord;
 
@@ -15,10 +17,10 @@ impl Config {
 		}
 	}
 
-	pub fn new_from_env() -> Self {
+	pub fn from_env() -> Result<Self> {
 		let bot = bot::Config::from_env();
-		let discord = discord::Config::from_env();
+		let discord = discord::Config::from_env()?;
 
-		Self::new(bot, discord)
+		Ok(Self::new(bot, discord))
 	}
 }

src/handlers/event/block_reaction.rs

@@ -0,0 +1,39 @@
+use crate::Data;
+
+use chrono::Duration;
+use eyre::{Context as _, Result};
+use log::{debug, trace};
+use poise::serenity_prelude::{Context, Reaction, Timestamp};
+
+pub async fn handle(ctx: &Context, reaction: &Reaction, data: &Data) -> Result<()> {
+	let reaction_type = reaction.emoji.clone();
+	let reactor = reaction.user_id;
+	let message = reaction.message(ctx).await.wrap_err_with(|| {
+		format!(
+			"Couldn't get message {} from reaction! We won't be able to check if it's old",
+			reaction.message_id
+		)
+	})?;
+
+	let time_sent = message.timestamp.to_utc();
+	let age = Timestamp::now().signed_duration_since(time_sent);
+	let max_days = Duration::days(data.config.discord.days_to_delete_reaction);
+
+	if age >= max_days {
+		// NOTE: if we for some reason **didn't** get the user_id associated with the reaction,
+		// this will clear **all** reactions of this type. this is intentional as older reactions
+		// being removed > harmful reactions being kept
+		debug!(
+			"Removing reaction {reaction_type} from message {}",
+			message.id
+		);
+		message.delete_reaction(ctx, reactor, reaction_type).await?;
+	} else {
+		trace!(
+			"Keeping reaction {reaction_type} for message {}",
+			message.id
+		);
+	}
+
+	Ok(())
+}

src/handlers/event/mod.rs

@@ -5,6 +5,7 @@ use poise::serenity_prelude::{ActivityData, Context, FullEvent, OnlineStatus};
 use poise::FrameworkContext;
 
 mod analyze_logs;
+mod block_reaction;
 mod delete_on_reaction;
 mod eta;
 mod expand_link;
@@ -71,6 +72,8 @@ pub async fn handle(
 				add_reaction.message_id.to_string(),
 				add_reaction.user_id.unwrap_or_default().to_string()
 			);
+
+			block_reaction::handle(ctx, add_reaction, data).await?;
 			delete_on_reaction::handle(ctx, add_reaction).await?;
 		}
 

src/main.rs

@@ -37,7 +37,7 @@ async fn setup(
 	_: &serenity::Ready,
 	framework: &Framework<Data, Error>,
 ) -> Result<Data, Error> {
-	let config = Config::new_from_env();
+	let config = Config::from_env()?;
 
 	let storage = if let Some(url) = &config.bot.redis_url {
 		Some(Storage::from_url(url)?)