Route which lets clients determine messages that have updated / deleted.

src/routes/users/find_mutual.rs

@@ -0,0 +1,41 @@
+use crate::database::*;
+use crate::util::result::{Error, Result};
+
+use futures::StreamExt;
+use mongodb::options::FindOptions;
+use mongodb::bson::{Document, doc};
+use rocket_contrib::json::JsonValue;
+
+#[get("/<target>/mutual")]
+pub async fn req(user: User, target: Ref) -> Result<JsonValue> {
+    let channels = get_collection("channels")
+        .find(
+            doc! {
+                "$or": [
+                    { "type": "Group" },
+                ],
+                "$and": [
+                    { "recipients": &user.id },
+                    { "recipients": &target.id }
+                ]
+            },
+            FindOptions::builder()
+                .projection(doc! { "_id": 1 })
+                .build()
+        )
+        .await
+        .map_err(|_| Error::DatabaseError {
+            operation: "find",
+            with: "channels",
+        })?
+        .filter_map(async move |s| s.ok())
+        .collect::<Vec<Document>>()
+        .await
+        .into_iter()
+        .filter_map(|x| x.get_str("_id").ok().map(|x| x.to_string()))
+        .collect::<Vec<String>>();
+
+    Ok(json!({
+        "channels": channels
+    }))
+}

src/routes/users/mod.rs

@@ -6,6 +6,7 @@ mod fetch_dms;
 mod fetch_relationship;
 mod fetch_relationships;
 mod fetch_user;
+mod find_mutual;
 mod get_avatar;
 mod get_default_avatar;
 mod open_dm;
@@ -22,6 +23,7 @@ pub fn routes() -> Vec<Route> {
         fetch_dms::req,
         open_dm::req,
         // Relationships
+        find_mutual::req,
         fetch_relationships::req,
         fetch_relationship::req,
         add_friend::req,