fix(err): structured context, liveness often (#26275)

rust/cymbal/src/frames/mod.rs

@@ -68,7 +68,20 @@ pub struct Frame {
     // it should never go in clickhouse / be queried over, but we do store it in PG for
     // use in the frontend
     #[serde(skip)]
-    pub context: Option<String>,
+    pub context: Option<Context>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq)]
+pub struct Context {
+    pub before: Vec<ContextLine>,
+    pub line: ContextLine,
+    pub after: Vec<ContextLine>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq)]
+pub struct ContextLine {
+    number: u32,
+    line: String,
 }
 
 impl Frame {
@@ -98,3 +111,12 @@ impl Frame {
         h.update(self.lang.as_bytes());
     }
 }
+
+impl ContextLine {
+    pub fn new(number: u32, line: impl ToString) -> Self {
+        Self {
+            number,
+            line: line.to_string(),
+        }
+    }
+}

rust/cymbal/src/frames/records.rs

@@ -6,7 +6,7 @@ use uuid::Uuid;
 
 use crate::error::UnhandledError;
 
-use super::Frame;
+use super::{Context, Frame};
 
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub struct ErrorTrackingStackFrame {
@@ -16,7 +16,7 @@ pub struct ErrorTrackingStackFrame {
     pub symbol_set_id: Option<Uuid>,
     pub contents: Frame,
     pub resolved: bool,
-    pub context: Option<String>,
+    pub context: Option<Context>,
 }
 
 impl ErrorTrackingStackFrame {
@@ -26,7 +26,7 @@ impl ErrorTrackingStackFrame {
         symbol_set_id: Option<Uuid>,
         contents: Frame,
         resolved: bool,
-        context: Option<String>,
+        context: Option<Context>,
     ) -> Self {
         Self {
             raw_id,
@@ -61,7 +61,7 @@ impl ErrorTrackingStackFrame {
             serde_json::to_value(&self.contents)?,
             self.resolved,
             Uuid::now_v7(),
-            self.context
+            serde_json::to_string(&self.context)?
         ).execute(e).await?;
         Ok(())
     }
@@ -103,9 +103,16 @@ impl ErrorTrackingStackFrame {
         // We don't serialise frame contexts on the Frame itself, but save it on the frame record,
         // and so when we load a frame record we need to patch back up the context onto the frame,
         // since we dropped it when we serialised the frame during saving.
-
         let mut frame: Frame = serde_json::from_value(found.contents)?;
-        frame.context = found.context.clone();
+        let context = if let Some(context) = found.context.as_ref() {
+            // We serialise the frame context as a json string, but it's a structure we have to manually
+            // deserialise back into the frame.
+            Some(serde_json::from_str(context)?)
+        } else {
+            None
+        };
+
+        frame.context = context.clone();
 
         Ok(Some(Self {
             raw_id: found.raw_id,
@@ -114,7 +121,7 @@ impl ErrorTrackingStackFrame {
             symbol_set_id: found.symbol_set_id,
             contents: frame,
             resolved: found.resolved,
-            context: found.context,
+            context,
         }))
     }
 }

rust/cymbal/src/langs/js.rs

@@ -1,5 +1,3 @@
-use std::cmp::min;
-
 use reqwest::Url;
 use serde::{Deserialize, Serialize};
 use sha2::{Digest, Sha512};
@@ -7,7 +5,7 @@ use sourcemap::{SourceMap, Token};
 
 use crate::{
     error::{Error, FrameError, JsResolveErr, UnhandledError},
-    frames::Frame,
+    frames::{Context, ContextLine, Frame},
     metric_consts::{FRAME_NOT_RESOLVED, FRAME_RESOLVED},
     symbol_store::SymbolCatalog,
 };
@@ -160,28 +158,37 @@ impl From<(&RawJSFrame, JsResolveErr)> for Frame {
     }
 }
 
-fn get_context(token: &Token) -> Option<String> {
+fn get_context(token: &Token) -> Option<Context> {
     let sv = token.get_source_view()?;
 
-    let token_line = token.get_src_line();
-    let start_line = token_line.saturating_sub(5);
-    let end_line = min(token_line.saturating_add(5) as usize, sv.line_count()) as u32;
+    let token_line_num = token.get_src_line();
 
-    // Rough guess on capacity here
-    let mut context = String::with_capacity(((end_line - start_line) * 100) as usize);
+    let token_line = sv.get_line(token_line_num)?;
 
-    for line in start_line..end_line {
-        if let Some(l) = sv.get_line(line) {
-            context.push_str(l);
-            context.push('\n');
+    let mut before = Vec::new();
+    let mut i = token_line_num;
+    while before.len() < 5 && i > 0 {
+        i -= 1;
+        if let Some(line) = sv.get_line(i) {
+            before.push(ContextLine::new(i, line));
+        }
+    }
+    before.reverse();
+
+    let mut after = Vec::new();
+    let mut i = token_line_num;
+    while after.len() < 5 && i < sv.line_count() as u32 {
+        i += 1;
+        if let Some(line) = sv.get_line(i) {
+            after.push(ContextLine::new(i, line));
         }
     }
 
-    if !context.is_empty() {
-        Some(context)
-    } else {
-        None
-    }
+    Some(Context {
+        before,
+        line: ContextLine::new(token_line_num, token_line),
+        after,
+    })
 }
 
 #[cfg(test)]

rust/cymbal/src/lib.rs

@@ -108,10 +108,13 @@ async fn process_exception(
         // process those groups in-order (but the individual frames in them can still be
         // thrown at the wall), with some cross-group concurrency.
         handles.push(tokio::spawn(async move {
-            context
+            context.worker_liveness.report_healthy().await;
+            let res = context
                 .resolver
                 .resolve(&frame, team_id, &context.pool, &context.catalog)
-                .await
+                .await;
+            context.worker_liveness.report_healthy().await;
+            res
         }));
     }