additional comments and todos

Author: wlmyng

crates/sui-indexer-alt-graphql/src/api/types/transaction/mod.rs

@@ -238,9 +238,9 @@ impl TransactionContents {
                 return Ok(None);
             };
 
-            // Unlike `effectsJson`, no server fetch: the rendered transaction proto is a pure
-            // function of the transaction BCS (no server-side joins), so local conversion is
-            // complete.
+            // `merge_transaction_data` (`sui-types/src/rpc_proto_conversions.rs`) derives every
+            // `Transaction` proto field from the decoded `TransactionData` alone, so local
+            // conversion is equivalent to the json produced from the proto transaction.
             let mut proto_transaction = content.proto_transaction()?;
             // Clear the bcs field as transactionJson is intended to provide a full structured output
             proto_transaction.bcs = None;

crates/sui-indexer-alt-graphql/src/api/types/transaction_effects.rs

@@ -372,9 +372,16 @@ impl EffectsContents {
         Some(
             async {
                 // Prefer the proto cached from an execution or streaming response (rendered by the
-                // fullnode). Otherwise ask the ledger service to render the effects. The local
-                // effects BCS is a fall back, and will likely be missing information like object
-                // type annotations and runtime-loaded objects.
+                // fullnode). Otherwise ask the ledger service to render the effects.
+                //
+                // TODO: fullnode-rendered protos also include clever error rendering, which
+                // sui-kv-rpc does not implement (though it has the package resolver required).
+                //
+                // TODO: The local BCS conversion is a transitional fallback, reachable only on the
+                // pg / direct-bigtable `KvLoader` variants (no ledger service to ask). It lacks
+                // object type annotations and runtime-loaded objects, which are not derivable from
+                // the effects BCS. These paths will be unreachable once the variants are
+                // deprecated.
                 let mut proto_effects = if let Some(proto) = content.cached_proto_effects() {
                     proto.clone()
                 } else {