Fetch messages route.

src/routes/channels/message_fetch.rs

@@ -0,0 +1,67 @@
+use crate::database::*;
+use crate::util::result::{Error, Result};
+
+use futures::StreamExt;
+use validator::Validate;
+use rocket::request::Form;
+use serde::{Serialize, Deserialize};
+use rocket_contrib::json::JsonValue;
+use mongodb::{bson::{doc, from_document}, options::FindOptions};
+
+#[derive(Validate, Serialize, Deserialize, FromForm)]
+pub struct Options {
+    #[validate(range(min = 1, max = 100))]
+    limit: Option<i64>,
+    #[validate(length(min = 26, max = 26))]
+    before: Option<String>,
+    #[validate(length(min = 26, max = 26))]
+    after: Option<String>,
+}
+
+#[get("/<target>/messages?<options..>")]
+pub async fn req(user: User, target: Ref, options: Form<Options>) -> Result<JsonValue> {
+    options.validate()
+        .map_err(|error| Error::FailedValidation { error })?;
+
+    let target = target.fetch_channel().await?;
+
+    let perm = permissions::channel::calculate(&user, &target).await;
+    if !perm.get_view() {
+        Err(Error::LabelMe)?
+    }
+
+    let mut query = doc! { "channel": target.id() };
+
+    if let Some(before) = &options.before {
+        query.insert("_id", doc! { "$lt": before });
+    }
+
+    if let Some(after) = &options.after {
+        query.insert("_id", doc! { "$gt": after });
+    }
+
+    let mut cursor = get_collection("messages")
+        .find(
+            query,
+            FindOptions::builder()
+                .limit(options.limit.unwrap_or(50))
+                .sort(doc! {
+                    "_id": -1
+                })
+                .build(),
+        )
+        .await
+        .map_err(|_| Error::DatabaseError { operation: "find", with: "messages" })?;
+    
+    let mut messages = vec![];
+    while let Some(result) = cursor.next().await {
+        if let Ok(doc) = result {
+            messages.push(
+                from_document::<Message>(doc)
+                    .map_err(|_| Error::DatabaseError { operation: "from_document", with: "message" })?
+            );
+        }
+    }
+
+    Ok(json!(messages))
+}

src/routes/channels/mod.rs

@@ -3,11 +3,13 @@ use rocket::Route;
 mod fetch_channel;
 mod delete_channel;
 mod message_send;
+mod message_fetch;
 
 pub fn routes() -> Vec<Route> {
     routes![
         fetch_channel::req,
         delete_channel::req,
-        message_send::req
+        message_send::req,
+        message_fetch::req
     ]
 }