feat(tasks): implement web push

src/tasks/web_push.rs

@@ -0,0 +1,91 @@
+use crate::util::variables::VAPID_PRIVATE_KEY;
+
+use deadqueue::limited::Queue;
+use futures::StreamExt;
+use rauth::entities::Session;
+use revolt_quark::{bson::doc, r#impl::mongo::MongoDb, Database};
+use web_push::{
+    ContentEncoding, SubscriptionInfo, SubscriptionKeys, VapidSignatureBuilder, WebPushClient,
+    WebPushMessageBuilder,
+};
+
+#[derive(Debug)]
+struct PushTask {
+    recipients: Vec<String>,
+    payload: String,
+}
+
+lazy_static! {
+    static ref Q: Queue<PushTask> = Queue::new(10_000);
+}
+
+pub async fn queue(recipients: Vec<String>, payload: String) {
+    if recipients.is_empty() {
+        return;
+    }
+
+    Q.push(PushTask {
+        recipients,
+        payload,
+    })
+    .await;
+}
+
+pub async fn worker(db: Database) {
+    let client = WebPushClient::new();
+    let key = base64::decode_config(VAPID_PRIVATE_KEY.clone(), base64::URL_SAFE)
+        .expect("valid `VAPID_PRIVATE_KEY`");
+
+    if let Database::MongoDb(MongoDb(db)) = db {
+        loop {
+            let task = Q.pop().await;
+
+            // ! FIXME: this is hard-coded until rauth is merged into quark
+            if let Ok(mut cursor) = db
+                .database("revolt")
+                .collection::<Session>("sessions")
+                .find(
+                    doc! {
+                        "user_id": {
+                            "$in": task.recipients
+                        },
+                        "subscription": {
+                            "$exists": true
+                        }
+                    },
+                    None,
+                )
+                .await
+            {
+                while let Some(Ok(session)) = cursor.next().await {
+                    if let Some(sub) = session.subscription {
+                        let subscription = SubscriptionInfo {
+                            endpoint: sub.endpoint,
+                            keys: SubscriptionKeys {
+                                auth: sub.auth,
+                                p256dh: sub.p256dh,
+                            },
+                        };
+
+                        let mut builder = WebPushMessageBuilder::new(&subscription).unwrap();
+                        let sig_builder = VapidSignatureBuilder::from_pem(
+                            std::io::Cursor::new(&key),
+                            &subscription,
+                        )
+                        .unwrap();
+
+                        let signature = sig_builder.build().unwrap();
+                        builder.set_vapid_signature(signature);
+                        builder.set_payload(ContentEncoding::AesGcm, task.payload.as_bytes());
+
+                        let msg = builder.build().unwrap();
+                        match client.send(msg).await {
+                            Ok(_) => info!("Sent Web Push notification to {:?}.", session.id),
+                            Err(err) => error!("Hit error sending Web Push! {:?}", err),
+                        }
+                    }
+                }
+            }
+        }
+    }
+}