feat(messaging): cap total text content to 2k characters

crates/delta/src/routes/channels/message_edit.rs

@@ -36,6 +36,8 @@ pub async fn req(
     edit.validate()
         .map_err(|error| Error::FailedValidation { error })?;
 
+    Message::validate_sum(&edit.content, &edit.embeds)?;
+
     let mut message = msg.as_message(db).await?;
     if message.channel != target {
         return Err(Error::NotFound);

crates/delta/src/routes/channels/message_send.rs

@@ -33,6 +33,8 @@ pub struct DataMessageSend {
     /// Messages to reply to
     replies: Option<Vec<Reply>>,
     /// Embeds to include in message
+    ///
+    /// Text embed content contributes to the content length cap
     #[validate(length(min = 1, max = 10))]
     embeds: Option<Vec<SendableEmbed>>,
     /// Masquerade to apply to this message
@@ -61,6 +63,8 @@ pub async fn message_send(
     data.validate()
         .map_err(|error| Error::FailedValidation { error })?;
 
+    Message::validate_sum(&data.content, &data.embeds)?;
+
     idempotency.consume_nonce(data.nonce).await?;
 
     let channel = target.as_channel(db).await?;

crates/quark/src/impl/generic/channels/message.rs

@@ -166,6 +166,31 @@ impl Message {
         .await;
         Ok(())
     }
+
+    /// Validate the sum of content of a message is under threshold
+    pub fn validate_sum(
+        content: &Option<String>,
+        embeds: &Option<Vec<SendableEmbed>>,
+    ) -> Result<()> {
+        let mut running_total = 0;
+        if let Some(content) = content {
+            running_total += content.len();
+        }
+
+        if let Some(embeds) = embeds {
+            for embed in embeds {
+                if let Some(desc) = &embed.description {
+                    running_total += desc.len();
+                }
+            }
+        }
+
+        if running_total <= 2000 {
+            Ok(())
+        } else {
+            Err(Error::PayloadTooLarge)
+        }
+    }
 }
 
 pub trait IntoUsers {

crates/quark/src/util/result.rs

@@ -41,6 +41,7 @@ pub enum Error {
     TooManyAttachments,
     TooManyReplies,
     EmptyMessage,
+    PayloadTooLarge,
     CannotRemoveYourself,
     GroupTooLarge {
         max: usize,
@@ -145,6 +146,7 @@ impl<'r> Responder<'r, 'static> for Error {
             Error::TooManyAttachments => Status::BadRequest,
             Error::TooManyReplies => Status::BadRequest,
             Error::EmptyMessage => Status::UnprocessableEntity,
+            Error::PayloadTooLarge => Status::UnprocessableEntity,
             Error::CannotRemoveYourself => Status::BadRequest,
             Error::GroupTooLarge { .. } => Status::Forbidden,
             Error::AlreadyInGroup => Status::Conflict,