fix(loki sink): use json size of unencoded event

src/sinks/loki/event.rs

@@ -139,21 +139,6 @@ impl ByteSizeOf for LokiEvent {
     }
 }
 
-/// This implementation approximates the `Serialize` implementation below, without any allocations.
-impl EstimatedJsonEncodedSizeOf for LokiEvent {
-    fn estimated_json_encoded_size_of(&self) -> JsonSize {
-        static BRACKETS_SIZE: JsonSize = JsonSize::new(2);
-        static COLON_SIZE: JsonSize = JsonSize::new(1);
-        static QUOTES_SIZE: JsonSize = JsonSize::new(2);
-
-        BRACKETS_SIZE
-            + QUOTES_SIZE
-            + self.timestamp.estimated_json_encoded_size_of()
-            + COLON_SIZE
-            + self.event.estimated_json_encoded_size_of()
-    }
-}
-
 impl Serialize for LokiEvent {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
     where
@@ -172,6 +157,7 @@ pub struct LokiRecord {
     pub partition: PartitionKey,
     pub labels: Labels,
     pub event: LokiEvent,
+    pub json_byte_size: JsonSize,
     pub finalizers: EventFinalizers,
 }
 
@@ -187,7 +173,7 @@ impl ByteSizeOf for LokiRecord {
 
 impl EstimatedJsonEncodedSizeOf for LokiRecord {
     fn estimated_json_encoded_size_of(&self) -> JsonSize {
-        self.event.estimated_json_encoded_size_of()
+        self.json_byte_size
     }
 }
 

src/sinks/loki/sink.rs

@@ -12,7 +12,7 @@ use vector_core::{
     partition::Partitioner,
     sink::StreamSink,
     stream::BatcherSettings,
-    ByteSizeOf,
+    ByteSizeOf, EstimatedJsonEncodedSizeOf,
 };
 
 use super::{
@@ -268,6 +268,7 @@ impl EventEncoder {
     pub(super) fn encode_event(&mut self, mut event: Event) -> Option<LokiRecord> {
         let tenant_id = self.key_partitioner.partition(&event);
         let finalizers = event.take_finalizers();
+        let json_byte_size = event.estimated_json_encoded_size_of();
         let mut labels = self.build_labels(&event);
         self.remove_label_fields(&mut event);
 
@@ -302,6 +303,7 @@ impl EventEncoder {
             },
             partition,
             finalizers,
+            json_byte_size,
         })
     }
 }