Files
signed/crates/signed_state/src/backend.rs
T

505 lines
16 KiB
Rust

use std::time::Duration;
use anyhow::{Error, anyhow};
use gpui::{App, AppContext, Context, Entity, EventEmitter, Global, Task};
use nostr_connect::prelude::*;
use nostr_sdk::prelude::*;
use signed_core::filters;
use signed_nostr::{NostrBackend, SignedAuthUrlHandler, UniversalSigner, Update};
/// Keyring entry holding the user credential (`nsec1...` or `bunker://...`).
pub const USER_KEYRING: &str = "su.reya.signed#user";
/// Keyring entry holding the locally generated key for NIP-46 sessions.
pub const MASTER_KEYRING: &str = "su.reya.signed#master";
/// Timeout for NIP-46 signer responses.
pub const NOSTR_CONNECT_TIMEOUT: u64 = 60;
/// Relays connected at startup, before any user-specific relay config is known.
pub const BOOTSTRAP_RELAYS: [&str; 4] = [
"wss://relay.primal.net",
"wss://relay.ditto.pub",
"wss://index.ngit.dev",
"wss://profiles.nostr1.com",
];
/// Relays used for indexing user's relay list (NIP-65).
pub const INDEXER_RELAYS: [&str; 3] = [
"wss://indexer.coracle.social",
"wss://purplepag.es",
"wss://user.kindpag.es",
];
#[derive(Debug, Clone)]
pub enum BackendEvent {
/// User has no signer configured.
SignerRequired,
/// The signer has changed (login/logout/account switch).
SignerChanged,
/// Relay bootstrap finished.
Connected,
/// A new event was received from a relay and stored in the database.
NostrUpdate(Update),
/// An event built locally was signed, broadcast and stored.
Published(Box<Event>),
/// An error occurred.
Error(String),
}
impl BackendEvent {
pub fn error<T>(error: T) -> Self
where
T: Into<String>,
{
Self::Error(error.into())
}
}
/// Global backend entity: owns the nostr client, the signer and the
/// notification pump. Stores subscribe to [`BackendEvent`] and re-query the
/// local database when relevant updates arrive.
pub struct Backend {
inner: NostrBackend,
current_user: Option<PublicKey>,
tasks: Vec<Task<Result<(), Error>>>,
}
struct GlobalBackend(Entity<Backend>);
impl Global for GlobalBackend {}
impl EventEmitter<BackendEvent> for Backend {}
impl Backend {
/// Retrieve the global backend.
pub fn global(cx: &App) -> Entity<Self> {
cx.global::<GlobalBackend>().0.clone()
}
pub(crate) fn set_global(entity: Entity<Self>, cx: &mut App) {
cx.set_global(GlobalBackend(entity));
}
pub(crate) fn new(inner: NostrBackend, cx: &mut Context<Self>) -> Self {
let client = inner.client();
let pump = cx.spawn(async move |this, cx| {
let mut notifications = client.notifications();
while let Some(notification) = notifications.next().await {
let ClientNotification::Event { event, .. } = notification else {
continue;
};
let update = Update::from_event(&event);
if this
.update(cx, |_, cx| cx.emit(BackendEvent::NostrUpdate(update)))
.is_err()
{
break;
}
}
Ok(())
});
let mut this = Self {
inner,
current_user: None,
tasks: vec![pump],
};
this.bootstrap(cx);
this
}
/// Bootstrap the client: connect to the default relays (indexers as
/// discovery-only) and restore the saved session, if any.
fn bootstrap(&mut self, cx: &mut Context<Self>) {
let backend = self.inner.clone();
let task = cx.background_spawn(async move {
for url in BOOTSTRAP_RELAYS {
backend.add_relay(url).await?;
}
for url in INDEXER_RELAYS {
backend.add_discovery_relay(url).await?;
}
backend.connect().await;
Ok::<(), Error>(())
});
self.tasks.push(cx.spawn(async move |this, cx| {
match task.await {
Ok(()) => {
this.update(cx, |_this, cx| cx.emit(BackendEvent::Connected))?;
}
Err(e) => {
this.update(cx, |_this, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
}
Ok(())
}));
self.restore_session(cx);
}
/// Restore the saved session from the keyring. Emits
/// [`BackendEvent::SignerRequired`] if no credential is stored.
pub fn restore_session(&mut self, cx: &mut Context<Self>) {
if cfg!(target_arch = "wasm32") {
cx.emit(BackendEvent::SignerRequired);
return;
}
let user = cx.read_credentials(USER_KEYRING);
let master = self.master_key(cx);
self.tasks.push(cx.spawn(async move |this, cx| {
let content = match user.await {
Ok(Some((_username, secret))) => String::from_utf8(secret)?,
_ => {
this.update(cx, |_, cx| cx.emit(BackendEvent::SignerRequired))?;
return Ok(());
}
};
let result = async {
if content.starts_with("nsec1") {
let keys = Keys::new(SecretKey::parse(&content)?);
this.update(cx, |this, cx| this.set_signer(keys, cx))?;
} else if content.starts_with("bunker://") {
let uri = NostrConnectUri::parse(&content)?;
let mut signer = NostrConnect::new(
uri,
master.await,
Duration::from_secs(NOSTR_CONNECT_TIMEOUT),
None,
)?;
signer.auth_url_handler(SignedAuthUrlHandler);
this.update(cx, |this, cx| this.set_signer(signer, cx))?;
} else {
this.update(cx, |_, cx| cx.emit(BackendEvent::SignerRequired))?;
}
Ok::<_, Error>(())
}
.await;
if let Err(e) = result {
this.update(cx, |_, cx| {
cx.emit(BackendEvent::error(e.to_string()));
cx.emit(BackendEvent::SignerRequired);
})?;
}
Ok(())
}));
}
/// Login with an `nsec1...` secret key. The credential is verified by
/// the signer flow and persisted in the keyring.
pub fn login_with_nsec(&mut self, nsec: &str, cx: &mut Context<Self>) {
let nsec = nsec.trim().to_owned();
let keys = match SecretKey::parse(&nsec) {
Ok(secret) => Keys::new(secret),
Err(e) => {
cx.emit(BackendEvent::error(e.to_string()));
return;
}
};
let write =
cx.write_credentials(USER_KEYRING, &keys.public_key().to_hex(), nsec.as_bytes());
self.tasks.push(cx.spawn(async move |this, cx| {
if let Err(e) = write.await {
this.update(cx, |_, cx| cx.emit(BackendEvent::error(e.to_string())))?;
return Ok(());
}
this.update(cx, |this, cx| this.set_signer(keys, cx))?;
Ok(())
}));
}
/// Login with a `bunker://...` URI (NIP-46). The auth URL, if any, is
/// opened in the default browser. The credential is persisted in the
/// keyring after the signer proves reachable.
pub fn login_with_bunker(&mut self, uri: &str, cx: &mut Context<Self>) {
let uri_string = uri.trim().to_owned();
let connect_uri = match NostrConnectUri::parse(&uri_string) {
Ok(uri) => uri,
Err(e) => {
cx.emit(BackendEvent::error(e.to_string()));
return;
}
};
let master = self.master_key(cx);
let write = cx.write_credentials(USER_KEYRING, "bunker", uri_string.as_bytes());
self.tasks.push(cx.spawn(async move |this, cx| {
let result = async {
let mut signer = NostrConnect::new(
connect_uri,
master.await,
Duration::from_secs(NOSTR_CONNECT_TIMEOUT),
None,
)?;
signer.auth_url_handler(SignedAuthUrlHandler);
// Verify the signer before persisting the credential.
signer.get_public_key_async().await?;
write.await?;
this.update(cx, |this, cx| this.set_signer(signer, cx))?;
Ok::<_, Error>(())
}
.await;
if let Err(e) = result {
this.update(cx, |_, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
Ok(())
}));
}
/// Remove the saved credential and reset to an anonymous session.
pub fn logout(&mut self, cx: &mut Context<Self>) {
let delete = cx.delete_credentials(USER_KEYRING);
self.tasks.push(cx.spawn(async move |this, cx| {
delete.await.ok();
this.update(cx, |this, cx| {
this.inner.signer().swap_inner(Keys::generate());
this.current_user = None;
cx.emit(BackendEvent::SignerChanged);
cx.emit(BackendEvent::SignerRequired);
cx.notify();
})?;
Ok(())
}));
}
/// Get (or generate and persist) the key used for NIP-46 sessions.
fn master_key(&self, cx: &App) -> Task<Keys> {
let task = cx.read_credentials(MASTER_KEYRING);
cx.spawn(async move |cx| {
let (keys, new_key) = match task.await {
Ok(Some((_user, secret))) => match SecretKey::from_slice(&secret) {
Ok(secret_key) => (Keys::new(secret_key), false),
_ => (Keys::generate(), true),
},
_ => (Keys::generate(), true),
};
if new_key {
let username = keys.public_key().to_hex();
let password = keys.secret_key().to_secret_bytes();
cx.update(|cx| {
let task = cx.write_credentials(MASTER_KEYRING, &username, &password);
cx.background_spawn(async move { task.await.ok() }).detach();
});
}
keys
})
}
/// Fetch the user's grasp list (kind `10317`) and add the listed grasp
/// servers as relays.
fn bootstrap_user(&mut self, public_key: PublicKey, cx: &mut Context<Self>) {
let backend = self.inner.clone();
self.tasks.push(cx.spawn(async move |this, cx| {
let result = async {
let events = backend
.client()
.fetch_events(filters::grasp_list(public_key))
.await?;
let urls: Vec<String> = events
.into_iter()
.max_by_key(|e| e.created_at)
.map(|e| {
e.tags
.iter()
.filter(|t| t.kind() == "g")
.filter_map(|t| t.content().map(str::to_owned))
.collect()
})
.unwrap_or_default();
for url in urls {
backend.add_relay(&url).await.ok();
}
backend.connect().await;
Ok::<_, Error>(())
}
.await;
if let Err(e) = result {
this.update(cx, |_, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
Ok(())
}));
}
/// Get the nostr client.
pub fn client(&self) -> Client {
self.inner.client()
}
/// Get the current signer.
pub fn signer(&self) -> UniversalSigner {
self.inner.signer()
}
/// Get the current user's public key.
pub fn current_user(&self) -> Option<PublicKey> {
self.current_user
}
/// Update the signer (any type implementing the async signer traits,
/// e.g. `Keys`, `NostrConnect`, a browser extension proxy).
pub fn set_signer<T>(&mut self, new_signer: T, cx: &mut Context<Self>)
where
T: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + 'static,
<T as AsyncGetPublicKey>::Error: std::error::Error + Send + Sync + 'static,
<T as AsyncSignEvent>::Error: std::error::Error + Send + Sync + 'static,
<T as AsyncNip44>::Error: std::error::Error + Send + Sync + 'static,
{
let task = cx.spawn(async move |this, cx| {
match new_signer.get_public_key_async().await {
Ok(public_key) => {
this.update(cx, |this, cx| {
this.inner.signer().swap_inner(new_signer);
this.current_user = Some(public_key);
this.bootstrap_user(public_key, cx);
cx.emit(BackendEvent::SignerChanged);
cx.notify();
})?;
}
Err(e) => {
this.update(cx, |_this, cx| {
cx.emit(BackendEvent::error(e.to_string()));
})?;
}
}
Ok(())
});
self.tasks.push(task);
}
/// Add relays and connect to them.
pub fn add_relays(&mut self, urls: Vec<String>, cx: &mut Context<Self>) {
let backend = self.inner.clone();
let task = cx.background_spawn(async move {
for url in urls {
backend.add_relay(&url).await?;
}
backend.connect().await;
Ok::<(), Error>(())
});
self.tasks.push(cx.spawn(async move |this, cx| {
match task.await {
Ok(()) => {
this.update(cx, |_this, cx| cx.emit(BackendEvent::Connected))?;
}
Err(e) => {
this.update(cx, |_this, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
}
Ok(())
}));
}
/// Add relays used only for discovery (e.g. NIP-65 indexers) and
/// connect to them. No subscriptions or writes are routed through them.
pub fn add_discovery_relays(&mut self, urls: Vec<String>, cx: &mut Context<Self>) {
let backend = self.inner.clone();
let task = cx.background_spawn(async move {
for url in urls {
backend.add_discovery_relay(&url).await?;
}
backend.connect().await;
Ok::<(), Error>(())
});
self.tasks.push(cx.spawn(async move |this, cx| {
if let Err(e) = task.await {
this.update(cx, |_this, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
Ok(())
}));
}
/// Start a persistent subscription. Matching events are stored in the
/// database automatically and surface as [`BackendEvent::NostrUpdate`].
pub fn subscribe(&mut self, filter: Filter, cx: &mut Context<Self>) {
let backend = self.inner.clone();
let task = cx.background_spawn(async move { backend.subscribe(filter).await.map(|_| ()) });
self.tasks.push(cx.spawn(async move |this, cx| {
if let Err(e) = task.await {
this.update(cx, |_this, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
Ok(())
}));
}
/// Sign, broadcast and locally store an event. Emits
/// [`BackendEvent::Published`] on success so stores can refresh.
///
/// The returned receiver yields the outcome of this specific action,
/// so callers can show inline progress/errors instead of relying on
/// the global [`BackendEvent::Error`].
pub fn send(
&mut self,
builder: EventBuilder,
cx: &mut Context<Self>,
) -> flume::Receiver<Result<Event, Error>> {
let (tx, rx) = flume::bounded(1);
let backend = self.inner.clone();
let task = cx.background_spawn(async move { backend.send(builder).await });
self.tasks.push(cx.spawn(async move |this, cx| {
let result = task.await;
match &result {
Ok(event) => {
this.update(cx, |_this, cx| {
cx.emit(BackendEvent::Published(Box::new(event.clone())));
})?;
}
Err(e) => {
this.update(cx, |_this, cx| cx.emit(BackendEvent::error(e.to_string())))?;
}
}
tx.send_async(result)
.await
.map_err(|_| anyhow!("action result receiver dropped"))
}));
rx
}
}