Add abandoned_usernames table

Author: avirshup

crates/crates_io_database/src/models/abandoned_username.rs

@@ -0,0 +1,25 @@
+use crate::schema::abandoned_usernames;
+use chrono::{DateTime, Utc};
+use diesel::prelude::*;
+
+#[derive(Debug, Clone, Identifiable, HasQuery)]
+#[diesel(
+    table_name = abandoned_usernames,
+    check_for_backend(diesel::pg::Pg),
+)]
+pub struct AbandonedUsername {
+    pub id: i64,
+    pub username: String,
+    pub previous_user_id: Option<i32>,
+    pub abandoned_at: DateTime<Utc>,
+    pub available_at: DateTime<Utc>,
+}
+
+#[derive(Insertable, Debug)]
+#[diesel(table_name = abandoned_usernames, check_for_backend(diesel::pg::Pg))]
+pub struct NewAbandonedUsername<'a> {
+    pub username: &'a str,
+    pub previous_user_id: Option<i32>,
+    pub abandoned_at: &'a DateTime<Utc>,
+    pub available_at: &'a DateTime<Utc>,
+}

crates/crates_io_database/src/models/mod.rs

@@ -1,3 +1,4 @@
+pub use self::abandoned_username::{AbandonedUsername, NewAbandonedUsername};
 pub use self::action::{NewVersionOwnerAction, VersionAction, VersionOwnerAction};
 pub use self::category::{Category, CrateCategory, NewCategory};
 pub use self::cloudfront_invalidation_queue::{
@@ -23,6 +24,7 @@ pub use self::version::{NewVersion, TopVersions, Version};
 
 pub mod helpers;
 
+mod abandoned_username;
 mod action;
 pub mod category;
 mod cloudfront_invalidation_queue;

crates/crates_io_database/src/schema.rs

@@ -12,6 +12,25 @@ pub mod sql_types {
     pub struct Ltree;
 }
 
+diesel::table! {
+    use diesel::sql_types::*;
+    use diesel_full_text_search::Tsvector;
+
+    /// Usernames previously associated with users
+    abandoned_usernames (id) {
+        /// Date and time the user stopped using this username (due to name change, account deactivation, or similar)
+        abandoned_at -> Timestamptz,
+        /// Date and time this username will be available to other users
+        available_at -> Timestamptz,
+        /// Unique identifier of the `abandoned_usernames` row
+        id -> Int8,
+        /// The ID of the user who was using this username for this time period, or NULL if the user was deleted
+        previous_user_id -> Nullable<Int4>,
+        /// The abandoned username in question (use `canon_username()` for normalization, if needed)
+        username -> Varchar,
+    }
+}
+
 diesel::table! {
     use diesel::sql_types::*;
     use diesel_full_text_search::Tsvector;
@@ -768,6 +787,24 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    /// Representation of the `recent_crate_downloads` view.
+    ///
+    /// This data represents the downloads in the last 90 days.
+    /// This view does not contain realtime data.
+    /// It is refreshed by the `update-downloads` script.
+    recent_crate_downloads (crate_id) {
+        /// The `crate_id` column of the `recent_crate_downloads` view.
+        ///
+        /// Its SQL type is `Integer`.
+        crate_id -> Integer,
+        /// The `downloads` column of the `recent_crate_downloads` table.
+        ///
+        /// Its SQL type is `BigInt`.
+        downloads -> BigInt,
+    }
+}
+
 diesel::table! {
     use diesel::sql_types::*;
     use diesel_full_text_search::Tsvector;
@@ -791,24 +828,6 @@ diesel::table! {
     }
 }
 
-diesel::table! {
-    /// Representation of the `recent_crate_downloads` view.
-    ///
-    /// This data represents the downloads in the last 90 days.
-    /// This view does not contain realtime data.
-    /// It is refreshed by the `update-downloads` script.
-    recent_crate_downloads (crate_id) {
-        /// The `crate_id` column of the `recent_crate_downloads` view.
-        ///
-        /// Its SQL type is `Integer`.
-        crate_id -> Integer,
-        /// The `downloads` column of the `recent_crate_downloads` table.
-        ///
-        /// Its SQL type is `BigInt`.
-        downloads -> BigInt,
-    }
-}
-
 diesel::table! {
     use diesel::sql_types::*;
     use diesel_full_text_search::Tsvector;
@@ -1274,6 +1293,7 @@ diesel::table! {
     }
 }
 
+diesel::joinable!(abandoned_usernames -> users (previous_user_id));
 diesel::joinable!(api_tokens -> users (user_id));
 diesel::joinable!(crate_downloads -> crates (crate_id));
 diesel::joinable!(crate_owner_invitations -> crates (crate_id));
@@ -1309,6 +1329,7 @@ diesel::joinable!(versions -> users (published_by));
 diesel::joinable!(versions_published_by -> versions (version_id));
 
 diesel::allow_tables_to_appear_in_same_query!(
+    abandoned_usernames,
     api_tokens,
     background_jobs,
     categories,

crates/crates_io_database_dump/src/dump-db.toml

@@ -274,6 +274,15 @@ account_lock_until = "private"
 is_admin = "private"
 publish_notifications = "private"
 
+[abandoned_usernames]
+dependencies = ["users"]
+[abandoned_usernames.columns]
+id = "private"
+username = "private"
+previous_user_id = "private"
+abandoned_at = "private"
+available_at = "private"
+
 [version_downloads]
 dependencies = ["versions"]
 [version_downloads.columns]

migrations/2026-08-07-120000-0000_create_abandoned_usernames_table/down.sql

@@ -0,0 +1 @@
+DROP TABLE abandoned_usernames;

migrations/2026-08-07-120000-0000_create_abandoned_usernames_table/up.sql

@@ -0,0 +1,31 @@
+CREATE TABLE IF NOT EXISTS abandoned_usernames
+(
+    id           BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    username     VARCHAR     NOT NULL,
+    previous_user_id   INTEGER
+        CONSTRAINT fk_abandoned_usernames_previous_user_id
+            REFERENCES users
+            ON DELETE SET NULL,
+    abandoned_at TIMESTAMPTZ NOT NULL,
+    available_at TIMESTAMPTZ NOT NULL
+);
+
+COMMENT ON TABLE abandoned_usernames IS
+    'Usernames previously associated with users';
+COMMENT ON COLUMN abandoned_usernames.id IS
+    'Unique identifier of the `abandoned_usernames` row';
+COMMENT ON COLUMN abandoned_usernames.username IS
+    'The abandoned username in question (use `canon_username()` for normalization, if needed)';
+COMMENT ON COLUMN abandoned_usernames.previous_user_id IS
+    'The ID of the user who was using this username for this time period, or NULL if the user was deleted';
+COMMENT ON COLUMN abandoned_usernames.abandoned_at IS
+    'Date and time the user stopped using this username (due to name change, account deactivation, or similar)';
+COMMENT ON COLUMN abandoned_usernames.available_at IS
+    'Date and time this username will be available to other users';
+
+-- safety-assured:start
+-- This table doesn't exist yet, so creating this index concurrently isn't necessary.
+CREATE INDEX IF NOT EXISTS
+    abandoned_usernames_canon_username_index
+    ON abandoned_usernames (canon_username(username));
+-- safety-assured:end