Create APIs for inviting users.

5 files changed, 369 insertions, 0 deletions

diff --git a/src/invite/app.rs b/src/invite/app.rs
new file mode 100644
index 0000000..998b4f1
--- /dev/null
+++ b/src/invite/app.rs
@@ -0,0 +1,106 @@
+use chrono::TimeDelta;
+use sqlx::sqlite::SqlitePool;
+
+use super::{repo::Provider as _, Id, Invite, Summary};
+use crate::{
+    clock::DateTime,
+    db::NotFound as _,
+    event::repo::Provider as _,
+    login::{repo::Provider as _, Login, Password},
+    token::{repo::Provider as _, Secret},
+};
+
+pub struct Invites<'a> {
+    db: &'a SqlitePool,
+}
+
+impl<'a> Invites<'a> {
+    pub const fn new(db: &'a SqlitePool) -> Self {
+        Self { db }
+    }
+
+    pub async fn create(
+        &self,
+        issuer: &Login,
+        issued_at: &DateTime,
+    ) -> Result<Invite, sqlx::Error> {
+        let mut tx = self.db.begin().await?;
+        let invite = tx.invites().create(issuer, issued_at).await?;
+        tx.commit().await?;
+
+        Ok(invite)
+    }
+
+    pub async fn get(&self, invite: &Id) -> Result<Summary, Error> {
+        let mut tx = self.db.begin().await?;
+        let invite = tx
+            .invites()
+            .summary(invite)
+            .await
+            .not_found(|| Error::NotFound(invite.clone()))?;
+        tx.commit().await?;
+
+        Ok(invite)
+    }
+
+    pub async fn accept(
+        &self,
+        invite: &Id,
+        name: &str,
+        password: &Password,
+        accepted_at: &DateTime,
+    ) -> Result<Secret, AcceptError> {
+        let mut tx = self.db.begin().await?;
+        let invite = tx
+            .invites()
+            .by_id(invite)
+            .await
+            .not_found(|| AcceptError::NotFound(invite.clone()))?;
+        // Split the tx here so we don't block writes while we deal with the password,
+        // and don't deal with the password until we're fairly confident we can accept
+        // the invite. Final validation is in the next tx.
+        tx.commit().await?;
+
+        let password_hash = password.hash()?;
+
+        let mut tx = self.db.begin().await?;
+        // If the invite has been deleted or accepted in the interim, this step will
+        // catch it.
+        tx.invites().accept(&invite).await?;
+        let created = tx.sequence().next(accepted_at).await?;
+        let login = tx.logins().create(name, &password_hash, &created).await?;
+        let secret = tx.tokens().issue(&login, accepted_at).await?;
+        tx.commit().await?;
+
+        Ok(secret)
+    }
+
+    pub async fn expire(&self, relative_to: &DateTime) -> Result<(), sqlx::Error> {
+        // Somewhat arbitrarily, expire after one day.
+        let expire_at = relative_to.to_owned() - TimeDelta::days(1);
+
+        let mut tx = self.db.begin().await?;
+        tx.invites().expire(&expire_at).await?;
+        tx.commit().await?;
+
+        Ok(())
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("invite not found: {0}")]
+    NotFound(Id),
+    #[error(transparent)]
+    Database(#[from] sqlx::Error),
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum AcceptError {
+    #[error("invite not found: {0}")]
+    NotFound(Id),
+    #[error(transparent)]
+    Database(#[from] sqlx::Error),
+    #[error(transparent)]
+    PasswordHash(#[from] password_hash::Error),
+}
diff --git a/src/invite/id.rs b/src/invite/id.rs
new file mode 100644
index 0000000..bd53f1f
--- /dev/null
+++ b/src/invite/id.rs
@@ -0,0 +1,24 @@
+use crate::id::Id as BaseId;
+
+// Stable identifier for an invite Prefixed with `I`.
+#[derive(Clone, Debug, Eq, PartialEq, sqlx::Type, serde::Deserialize, serde::Serialize)]
+#[sqlx(transparent)]
+pub struct Id(BaseId);
+
+impl From<BaseId> for Id {
+    fn from(id: BaseId) -> Self {
+        Self(id)
+    }
+}
+
+impl Id {
+    pub fn generate() -> Self {
+        BaseId::generate("I")
+    }
+}
+
+impl std::fmt::Display for Id {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
+    }
+}
diff --git a/src/invite/mod.rs b/src/invite/mod.rs
new file mode 100644
index 0000000..5f9d490
--- /dev/null
+++ b/src/invite/mod.rs
@@ -0,0 +1,24 @@
+pub mod app;
+mod id;
+mod repo;
+mod routes;
+
+use crate::{
+    clock::DateTime,
+    login::{self, Login},
+};
+
+pub use self::{id::Id, routes::router};
+
+#[derive(Debug, serde::Serialize)]
+pub struct Invite {
+    pub id: Id,
+    pub issuer: login::Id,
+    pub issued_at: DateTime,
+}
+
+#[derive(serde::Serialize)]
+pub struct Summary {
+    pub issuer: Login,
+    pub issued_at: DateTime,
+}
diff --git a/src/invite/repo.rs b/src/invite/repo.rs
new file mode 100644
index 0000000..2ab993f
--- /dev/null
+++ b/src/invite/repo.rs
@@ -0,0 +1,121 @@
+use sqlx::{sqlite::Sqlite, SqliteConnection, Transaction};
+
+use super::{Id, Invite, Summary};
+use crate::{
+    clock::DateTime,
+    login::{self, Login},
+};
+
+pub trait Provider {
+    fn invites(&mut self) -> Invites;
+}
+
+impl<'c> Provider for Transaction<'c, Sqlite> {
+    fn invites(&mut self) -> Invites {
+        Invites(self)
+    }
+}
+
+pub struct Invites<'t>(&'t mut SqliteConnection);
+
+impl<'c> Invites<'c> {
+    pub async fn create(
+        &mut self,
+        issuer: &Login,
+        issued_at: &DateTime,
+    ) -> Result<Invite, sqlx::Error> {
+        let id = Id::generate();
+        let invite = sqlx::query_as!(
+            Invite,
+            r#"
+				insert into invite (id, issuer, issued_at)
+				values ($1, $2, $3)
+				returning
+					id as "id: Id",
+					issuer as "issuer: login::Id",
+					issued_at as "issued_at: DateTime"
+			"#,
+            id,
+            issuer.id,
+            issued_at
+        )
+        .fetch_one(&mut *self.0)
+        .await?;
+
+        Ok(invite)
+    }
+
+    pub async fn by_id(&mut self, invite: &Id) -> Result<Invite, sqlx::Error> {
+        let invite = sqlx::query_as!(
+            Invite,
+            r#"
+				select
+					id as "id: Id",
+					issuer as "issuer: login::Id",
+					issued_at as "issued_at: DateTime"
+				from invite
+				where id = $1
+			"#,
+            invite,
+        )
+        .fetch_one(&mut *self.0)
+        .await?;
+
+        Ok(invite)
+    }
+
+    pub async fn summary(&mut self, invite: &Id) -> Result<Summary, sqlx::Error> {
+        let invite = sqlx::query!(
+            r#"
+				select
+					issuer.id as "issuer_id: login::Id",
+					issuer.name as "issuer_name",
+					invite.issued_at as "invite_issued_at: DateTime"
+				from invite
+				join login as issuer on (invite.issuer = issuer.id)
+				where invite.id = $1
+			"#,
+            invite,
+        )
+        .map(|row| Summary {
+            issuer: Login {
+                id: row.issuer_id,
+                name: row.issuer_name,
+            },
+            issued_at: row.invite_issued_at,
+        })
+        .fetch_one(&mut *self.0)
+        .await?;
+
+        Ok(invite)
+    }
+
+    pub async fn accept(&mut self, invite: &Invite) -> Result<(), sqlx::Error> {
+        sqlx::query_scalar!(
+            r#"
+				delete from invite
+				where id = $1
+				returning 1 as "deleted: bool"
+			"#,
+            invite.id,
+        )
+        .fetch_one(&mut *self.0)
+        .await?;
+
+        Ok(())
+    }
+
+    pub async fn expire(&mut self, expire_at: &DateTime) -> Result<(), sqlx::Error> {
+        sqlx::query!(
+            r#"
+				delete from invite
+				where issued_at < $1
+			"#,
+            expire_at,
+        )
+        .execute(&mut *self.0)
+        .await?;
+
+        Ok(())
+    }
+}
diff --git a/src/invite/routes.rs b/src/invite/routes.rs
new file mode 100644
index 0000000..3384e10
--- /dev/null
+++ b/src/invite/routes.rs
@@ -0,0 +1,94 @@
+use axum::{
+    extract::{Json, Path, State},
+    http::StatusCode,
+    response::{IntoResponse, Response},
+    routing::{get, post},
+    Router,
+};
+
+use super::{app, Id, Invite, Summary};
+use crate::{
+    app::App,
+    clock::RequestedAt,
+    error::{Internal, NotFound},
+    login::{Login, Password},
+    token::extract::IdentityToken,
+};
+
+pub fn router() -> Router<App> {
+    Router::new()
+        .route("/api/invite", post(on_invite))
+        .route("/api/invite/:invite", get(invite))
+        .route("/api/invite/:invite", post(on_accept))
+}
+
+#[derive(serde::Deserialize)]
+struct InviteRequest {}
+
+async fn on_invite(
+    State(app): State<App>,
+    RequestedAt(issued_at): RequestedAt,
+    login: Login,
+    // Require `{}` as the only valid request for this endpoint.
+    _: Json<InviteRequest>,
+) -> Result<Json<Invite>, Internal> {
+    let invite = app.invites().create(&login, &issued_at).await?;
+    Ok(Json(invite))
+}
+
+async fn invite(
+    State(app): State<App>,
+    Path(invite): Path<Id>,
+) -> Result<Json<Summary>, InviteError> {
+    app.invites()
+        .get(&invite)
+        .await
+        .map(Json)
+        .map_err(InviteError)
+}
+
+struct InviteError(app::Error);
+
+impl IntoResponse for InviteError {
+    fn into_response(self) -> Response {
+        let Self(error) = self;
+        match error {
+            error @ app::Error::NotFound(_) => NotFound(error).into_response(),
+            other => Internal::from(other).into_response(),
+        }
+    }
+}
+
+#[derive(serde::Deserialize)]
+struct AcceptRequest {
+    name: String,
+    password: Password,
+}
+
+async fn on_accept(
+    State(app): State<App>,
+    RequestedAt(accepted_at): RequestedAt,
+    identity: IdentityToken,
+    Path(invite): Path<Id>,
+    Json(request): Json<AcceptRequest>,
+) -> Result<(IdentityToken, StatusCode), AcceptError> {
+    let secret = app
+        .invites()
+        .accept(&invite, &request.name, &request.password, &accepted_at)
+        .await
+        .map_err(AcceptError)?;
+    let identity = identity.set(secret);
+    Ok((identity, StatusCode::NO_CONTENT))
+}
+
+struct AcceptError(app::AcceptError);
+
+impl IntoResponse for AcceptError {
+    fn into_response(self) -> Response {
+        let Self(error) = self;
+        match error {
+            error @ app::AcceptError::NotFound(_) => NotFound(error).into_response(),
+            other => Internal::from(other).into_response(),
+        }
+    }
+}