Track event each time a user is deleted (#6025)

backend/canisters/user_index/CHANGELOG.md

@@ -14,6 +14,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Changed
 
 - Track event each time a proof of uniqueness is submitted ([#6024](https://github.com/open-chat-labs/open-chat/pull/6024))
+- Track event each time a user is deleted ([#6025](https://github.com/open-chat-labs/open-chat/pull/6025))
 
 ## [[2.0.1231](https://github.com/open-chat-labs/open-chat/releases/tag/v2.0.1231-user_index)] - 2024-07-08
 

backend/canisters/user_index/impl/src/lib.rs

@@ -6,7 +6,7 @@ use crate::timer_job_types::TimerJob;
 use candid::Principal;
 use canister_state_macros::canister_state;
 use canister_timer_jobs::TimerJobs;
-use event_store_producer::{EventStoreClient, EventStoreClientBuilder, EventStoreClientInfo};
+use event_store_producer::{EventBuilder, EventStoreClient, EventStoreClientBuilder, EventStoreClientInfo};
 use event_store_producer_cdk_runtime::CdkRuntime;
 use fire_and_forget_handler::FireAndForgetHandler;
 use icrc_ledger_types::icrc1::account::{Account, Subaccount};
@@ -158,6 +158,32 @@ impl RuntimeState {
         jobs::submit_message_to_modclub::start_job_if_required(self);
     }
 
+    pub fn delete_user(&mut self, user_id: UserId, triggered_by_user: bool) {
+        let now = self.env.now();
+        self.data.users.delete_user(user_id, now);
+        self.data.local_index_map.remove_user(&user_id);
+        self.data.empty_users.remove(&user_id);
+
+        #[derive(Serialize)]
+        struct EventPayload {
+            triggered_by_user: bool,
+        }
+
+        self.data.event_store_client.push(
+            EventBuilder::new("user_deleted", now)
+                .with_user(user_id.to_string(), true)
+                .with_source(self.env.canister_id().to_string(), false)
+                .with_json_payload(&EventPayload { triggered_by_user })
+                .build(),
+        );
+
+        self.data.deleted_users.push(DeletedUser {
+            user_id,
+            triggered_by_user,
+            timestamp: now,
+        });
+    }
+
     pub fn user_metrics(&self, user_id: UserId) -> Option<UserMetrics> {
         self.data.users.get_by_user_id(&user_id).map(|user| {
             let now = self.env.now();

backend/canisters/user_index/impl/src/updates/c2c_notify_events.rs

@@ -1,6 +1,6 @@
 use crate::guards::caller_is_local_user_index_canister;
 use crate::timer_job_types::{JoinUserToGroup, TimerJob};
-use crate::{mutate_state, DeletedUser, RuntimeState, UserRegisteredEventPayload, ONE_MB};
+use crate::{mutate_state, RuntimeState, UserRegisteredEventPayload, ONE_MB};
 use candid::Principal;
 use canister_api_macros::update_msgpack;
 use canister_tracing_macros::trace;
@@ -88,15 +88,7 @@ fn handle_event(event: Event, state: &mut RuntimeState) {
             );
         }
         Event::UserDeleted(ev) => {
-            let now = state.env.now();
-            state.data.users.delete_user(ev.user_id, now);
-            state.data.local_index_map.remove_user(&ev.user_id);
-            state.data.empty_users.remove(&ev.user_id);
-            state.data.deleted_users.push(DeletedUser {
-                user_id: ev.user_id,
-                triggered_by_user: false,
-                timestamp: now,
-            });
+            state.delete_user(ev.user_id, false);
             state.push_event_to_all_local_user_indexes(
                 LocalUserIndexEvent::DeleteUser(DeleteUser {
                     user_id: ev.user_id,

backend/canisters/user_index/impl/src/updates/delete_user.rs

@@ -1,4 +1,4 @@
-use crate::{mutate_state, DeletedUser, RuntimeState};
+use crate::{mutate_state, RuntimeState};
 use canister_tracing_macros::trace;
 use ic_cdk::update;
 use local_user_index_canister::{DeleteUser, Event};
@@ -20,13 +20,7 @@ fn delete_user_impl(args: Args, state: &mut RuntimeState) -> Response {
         return NotAuthorized;
     }
 
-    let now = state.env.now();
-    state.data.users.delete_user(args.user_id, now);
-    state.data.deleted_users.push(DeletedUser {
-        user_id: args.user_id,
-        triggered_by_user: true,
-        timestamp: now,
-    });
+    state.delete_user(args.user_id, true);
     state.push_event_to_all_local_user_indexes(
         Event::DeleteUser(DeleteUser {
             user_id: args.user_id,