Split `user` into a chat-facing entity and an authentication-facing entity.

The taxonomy is now as follows:

* A _login_ is someone's identity for the purposes of authenticating to the service. Logins are not synchronized, and in fact are not published anywhere in the current API. They have a login ID, a name and a password.

* A _user_ is someone's identity for the purpose of participating in conversations. Users _are_ synchronized, as before. They have a user ID, a name, and a creation instant for the purposes of synchronization.

In practice, a user exists for every login - in fact, users' names are stored in the login table and are joined in, rather than being stored redundantly in the user table. A login ID and its corresponding user ID are always equal, and the user and login ID types support conversion and comparison to facilitate their use in this context.

Tokens are now associated with logins, not users. The currently-acting identity is passed down into app types as a login, not a user, and then resolved to a user where appropriate within the app methods.

As a side effect, the `GET /api/boot` method now returns a `login` key instead of a `user` key. The structure of the nested value is unchanged.

1 files changed, 45 insertions, 44 deletions

diff --git a/src/user/repo.rs b/src/user/repo.rs
index bfb603d..aaf3b73 100644
--- a/src/user/repo.rs
+++ b/src/user/repo.rs
@@ -3,9 +3,10 @@ use sqlx::{SqliteConnection, Transaction, sqlite::Sqlite};
 
 use crate::{
     clock::DateTime,
+    db::NotFound,
     event::{Instant, Sequence},
+    login::Login,
     name::{self, Name},
-    password::StoredHash,
     user::{History, Id, User},
 };
 
@@ -24,71 +25,58 @@ pub struct Users<'t>(&'t mut SqliteConnection);
 impl Users<'_> {
     pub async fn create(
         &mut self,
-        name: &Name,
-        password: &StoredHash,
+        login: &Login,
         created: &Instant,
     ) -> Result<History, sqlx::Error> {
-        let id = Id::generate();
-        let display_name = name.display();
-        let canonical_name = name.canonical();
-
-        sqlx::query!(
-            r#"
-                insert into login (id, display_name, canonical_name, password)
-                values ($1, $2, $3, $4)
-            "#,
-            id,
-            display_name,
-            canonical_name,
-            password,
-        )
-        .execute(&mut *self.0)
-        .await?;
-
         sqlx::query!(
             r#"
                 insert into user (id, created_sequence, created_at)
                 values ($1, $2, $3)
             "#,
-            id,
+            login.id,
             created.sequence,
             created.at,
         )
         .execute(&mut *self.0)
         .await?;
 
-        let user = History {
-            created: *created,
+        Ok(History {
             user: User {
-                id,
-                name: name.clone(),
+                id: login.id.clone().into(),
+                name: login.name.clone(),
             },
-        };
-
-        Ok(user)
+            created: *created,
+        })
     }
 
-    pub async fn set_password(
-        &mut self,
-        login: &History,
-        to: &StoredHash,
-    ) -> Result<(), sqlx::Error> {
-        let login = login.id();
-
-        sqlx::query_scalar!(
+    pub async fn by_login(&mut self, login: &Login) -> Result<History, LoadError> {
+        let user = sqlx::query!(
             r#"
-                update login
-                set password = $1
-                where id = $2
-                returning id as "id: Id"
+                select
+                    id as "id: Id",
+                    login.display_name as "display_name: String",
+                    login.canonical_name as "canonical_name: String",
+                    user.created_at as "created_at: DateTime",
+                    user.created_sequence as "created_sequence: Sequence"
+                from user
+                join login using (id)
+                where id = $1
             "#,
-            to,
-            login,
+            login.id,
         )
+        .map(|row| {
+            Ok::<_, LoadError>(History {
+                user: User {
+                    id: row.id,
+                    name: Name::new(row.display_name, row.canonical_name)?,
+                },
+                created: Instant::new(row.created_at, row.created_sequence),
+            })
+        })
         .fetch_one(&mut *self.0)
-        .await?;
+        .await??;
 
-        Ok(())
+        Ok(user)
     }
 
     pub async fn all(&mut self, resume_at: Sequence) -> Result<Vec<History>, LoadError> {
@@ -163,3 +151,16 @@ pub enum LoadError {
     Database(#[from] sqlx::Error),
     Name(#[from] name::Error),
 }
+
+impl<T> NotFound for Result<T, LoadError> {
+    type Ok = T;
+    type Error = LoadError;
+
+    fn optional(self) -> Result<Option<T>, LoadError> {
+        match self {
+            Ok(value) => Ok(Some(value)),
+            Err(LoadError::Database(sqlx::Error::RowNotFound)) => Ok(None),
+            Err(other) => Err(other),
+        }
+    }
+}