From 27289c5f35cebe1d7b0251ce73f0dde0a11a99fd Mon Sep 17 00:00:00 2001
From: Nia Weiss <nia.weiss@molecula.com>
Date: Thu, 8 Oct 2020 09:53:11 -0400
Subject: [PATCH] split query batches in the executor

We previously had some significant bugs in which our error handling for translation would cause an entire batch of queries to silently fail.
This change processes each call seperately, such that all executable queries are processed.
---
 executor.go | 94 +++++++++++++++++++++++++++--------------------------
 1 file changed, 48 insertions(+), 46 deletions(-)

diff --git a/executor.go b/executor.go
index 2be9c8468..d4a4aea38 100644
--- a/executor.go
+++ b/executor.go
@@ -208,23 +208,6 @@ func (e *executor) Execute(ctx context.Context, index string, q *pql.Query, shar
 		opt = &execOptions{}
 	}
 
-	// Translate query keys to ids, if necessary.
-	// No need to translate a remote call.
-	if !opt.Remote {
-		if err := e.translateCalls(ctx, index, q.Calls); err != nil {
-			if errors.Cause(err) == ErrTranslatingKeyNotFound {
-				// No error - return empty result
-				resp.Results = make([]interface{}, len(q.Calls))
-				for i, c := range q.Calls {
-					resp.Results[i] = emptyResult(c)
-				}
-				return resp, nil
-			}
-			return resp, err
-		} else if err := validateQueryContext(ctx); err != nil {
-			return resp, err
-		}
-	}
 	if opt.Profile {
 		var prof tracing.ProfiledSpan
 		prof, ctx = tracing.StartProfiledSpanFromContext(ctx, "Execute")
@@ -235,24 +218,61 @@ func (e *executor) Execute(ctx context.Context, index string, q *pql.Query, shar
 			return resp, fmt.Errorf("profiling execution failed: %T is not tracing.Profile", prof)
 		}
 	}
-	results, err := e.execute(ctx, index, q, shards, opt)
-	if err != nil {
-		return resp, err
-	} else if err := validateQueryContext(ctx); err != nil {
-		return resp, err
+	resp.Results = make([]interface{}, len(q.Calls))
+	for i, c := range q.Calls {
+		resp.Results[i] = emptyResult(c)
 	}
+	var columnAttrsRows []*Row
+	for i, c := range q.Calls {
+		// Translate query keys to ids, if necessary.
+		// No need to translate a remote call.
+		if !opt.Remote {
+			if err := e.translateCalls(ctx, index, []*pql.Call{c}); err != nil {
+				if errors.Cause(err) == ErrTranslatingKeyNotFound {
+					// No error - return empty result
+					continue
+				}
+				return resp, err
+			} else if err := validateQueryContext(ctx); err != nil {
+				return resp, err
+			}
+		}
 
-	resp.Results = results
+		results, err := e.execute(ctx, index, &pql.Query{Calls: []*pql.Call{c}}, shards, opt)
+		if err != nil {
+			return resp, err
+		} else if err := validateQueryContext(ctx); err != nil {
+			return resp, err
+		}
+
+		if opt.ColumnAttrs {
+			if resultRow, ok := results[0].(*Row); ok {
+				columnAttrsRows = append(columnAttrsRows, resultRow)
+			}
+		}
+
+		// Translate response objects from ids to keys, if necessary.
+		// No need to translate a remote call.
+		if !opt.Remote {
+			if err := e.translateResults(ctx, index, idx, []*pql.Call{c}, results); err != nil {
+				if errors.Cause(err) == ErrTranslatingKeyNotFound {
+					// No error - return empty result
+					continue
+				}
+				return resp, err
+			} else if err := validateQueryContext(ctx); err != nil {
+				return resp, err
+			}
+		}
+
+		resp.Results[i] = results[0]
+	}
 
 	// Fill column attributes if requested.
 	if opt.ColumnAttrs {
 		// Consolidate all column ids across all calls.
 		var columnIDs []uint64
-		for _, result := range results {
-			bm, ok := result.(*Row)
-			if !ok {
-				continue
-			}
+		for _, bm := range columnAttrsRows {
 			columnIDs = uint64Slice(columnIDs).merge(bm.Columns())
 		}
 
@@ -282,24 +302,6 @@ func (e *executor) Execute(ctx context.Context, index string, q *pql.Query, shar
 		resp.ColumnAttrSets = columnAttrSets
 	}
 
-	// Translate response objects from ids to keys, if necessary.
-	// No need to translate a remote call.
-	if !opt.Remote {
-		if err := e.translateResults(ctx, index, idx, q.Calls, results); err != nil {
-			if errors.Cause(err) == ErrTranslatingKeyNotFound {
-				// No error - return empty result
-				resp.Results = make([]interface{}, len(q.Calls))
-				for i, c := range q.Calls {
-					resp.Results[i] = emptyResult(c)
-				}
-				return resp, nil
-			}
-			return resp, err
-		} else if err := validateQueryContext(ctx); err != nil {
-			return resp, err
-		}
-	}
-
 	return resp, nil
 }