add bot metric and rename guilds metric to guild

src/discord.rs

@@ -1,7 +1,7 @@
 use crate::metrics;
 use crate::metrics::{
-    ActivityLabels, BoostLabels, EmoteUsedLabels, GuildsLabels, MemberLabels, MemberStatusLabels,
-    MemberVoiceLabels, MessageSentLabels,
+    ActivityLabels, BoostLabels, BotLabels, EmoteUsedLabels, GuildsLabels, MemberLabels,
+    MemberStatusLabels, MemberVoiceLabels, MessageSentLabels,
 };
 use axum::async_trait;
 use serenity::all::{
@@ -82,9 +82,9 @@ impl EventHandler for Handler {
     async fn guild_create(&self, ctx: Context, guild: Guild, _is_new: Option<bool>) {
         info!(guild_id = guild.id.get(), "Guild create");
 
-        // Handle `guilds` metric
+        // Handle `guild` metric
         self.metrics_handler
-            .guilds
+            .guild
             .get_or_create(&GuildsLabels {
                 guild_id: guild.id.into(),
             })
@@ -106,6 +106,31 @@ impl EventHandler for Handler {
             })
             .set(guild.member_count as i64);
 
+        // Handle `bot` metric
+        'bot: {
+            let mut after = None;
+            loop {
+                let Ok(members) = guild.members(&ctx.http, None, after).await else {
+                    warn!(guild_id = guild.id.get(), "Failed to count guild bots");
+                    // remove metric to indicate no bots counted
+                    self.metrics_handler.bot.remove(&BotLabels {
+                        guild_id: guild.id.into(),
+                    });
+                    break 'bot;
+                };
+                self.metrics_handler
+                    .bot
+                    .get_or_create(&BotLabels {
+                        guild_id: guild.id.into(),
+                    })
+                    .inc_by(members.iter().filter(|member| member.user.bot).count() as i64);
+                let Some(last) = members.last() else {
+                    break 'bot;
+                };
+                after = Some(last.user.id);
+            }
+        }
+
         for (user_id, presence) in &guild.presences {
             debug!(user_id = user_id.get(), "create presence");
 
@@ -173,13 +198,21 @@ impl EventHandler for Handler {
     ) {
         info!(guild_id = incomplete.id.get(), "Guild delete");
 
-        // Handle `guilds` metric
+        // Handle `guild` metric
         self.metrics_handler
-            .guilds
+            .guild
             .get_or_create(&GuildsLabels {
                 guild_id: incomplete.id.into(),
             })
             .set(0);
+
+        // Handle `bot` metric
+        self.metrics_handler
+            .bot
+            .get_or_create(&BotLabels {
+                guild_id: incomplete.id.into(),
+            })
+            .set(0);
     }
 
     async fn guild_member_addition(&self, _ctx: Context, new_member: Member) {
@@ -196,6 +229,16 @@ impl EventHandler for Handler {
                 guild_id: new_member.guild_id.into(),
             })
             .inc();
+
+        // Handle `bot` metric
+        if new_member.user.bot {
+            self.metrics_handler
+                .bot
+                .get_or_create(&BotLabels {
+                    guild_id: new_member.guild_id.into(),
+                })
+                .inc();
+        }
     }
 
     async fn guild_member_removal(
@@ -218,6 +261,16 @@ impl EventHandler for Handler {
                 guild_id: guild_id.into(),
             })
             .inc();
+
+        // Handle `bot` metric
+        if user.bot {
+            self.metrics_handler
+                .bot
+                .get_or_create(&BotLabels {
+                    guild_id: guild_id.into(),
+                })
+                .dec();
+        }
     }
 
     async fn guild_update(

src/metrics.rs

@@ -92,6 +92,16 @@ pub(crate) struct MemberLabels {
     pub(crate) guild_id: u64,
 }
 
+/// [BotLabels] are the [labels](EncodeLabelSet) for the "bot" metric.
+///
+/// This metric is not included in the member metric (using a label) as the user bot status has to
+/// be explicitly requested on guild creation. As such, they are separated to ensure that the member
+/// metric does not suffer from additional requests (that could potentially fail).
+#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
+pub(crate) struct BotLabels {
+    pub(crate) guild_id: u64,
+}
+
 /// [MemberStatusLabels] are the [labels](EncodeLabelSet) for the "member_status" metric.
 #[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
 pub(crate) struct MemberStatusLabels {
@@ -122,9 +132,10 @@ pub(crate) struct BoostLabels {
 /// Handler is the [servable](serve) bundle of metrics for the exporter.
 pub(crate) struct Handler {
     registry: Registry,
-    pub(crate) guilds: Family<GuildsLabels, Gauge>,
+    pub(crate) guild: Family<GuildsLabels, Gauge>,
     pub(crate) message_sent: Family<MessageSentLabels, Counter>,
     pub(crate) member: Family<MemberLabels, Gauge>,
+    pub(crate) bot: Family<BotLabels, Gauge>,
     pub(crate) emote_used: Family<EmoteUsedLabels, Counter>,
     pub(crate) activity: Family<ActivityLabels, Gauge>,
     pub(crate) member_status: Family<MemberStatusLabels, Gauge>,
@@ -141,9 +152,13 @@ impl Handler {
         debug!(prefix = PREFIX, "Building metrics registry");
         let mut registry = <Registry>::with_prefix(PREFIX);
 
-        debug!(metrics_name = "guilds", "Building metric");
-        let guilds = Family::<GuildsLabels, Gauge>::default();
-        registry.register("guilds", "The total number of guilds.", guilds.clone());
+        debug!(metrics_name = "guild", "Building metric");
+        let guild = Family::<GuildsLabels, Gauge>::default();
+        registry.register(
+            "guild",
+            "The total number of guilds handled by the exporter.",
+            guild.clone(),
+        );
 
         debug!(metrics_name = "message_sent", "Building metric");
         let message_sent = Family::<MessageSentLabels, Counter>::default();
@@ -173,10 +188,18 @@ impl Handler {
         let member = Family::<MemberLabels, Gauge>::default();
         registry.register(
             "member",
-            "The total number of members on the guild.",
+            "The total number of members (including bots) on the guild.",
             member.clone(),
         );
 
+        debug!(metrics_name = "bot", "Building metric");
+        let bot = Family::<BotLabels, Gauge>::default();
+        registry.register(
+            "bot",
+            "The total number of bot members on the guild.",
+            bot.clone(),
+        );
+
         debug!(metrics_name = "member_status", "Building metric");
         let member_status = Family::<MemberStatusLabels, Gauge>::default();
         registry.register(
@@ -204,11 +227,12 @@ impl Handler {
         Self {
             registry,
             // metrics
-            guilds,
+            guild,
             message_sent,
             emote_used,
             activity,
             member,
+            bot,
             member_status,
             member_voice,
             boost,