Always create Cache object, so custom provenance can be created even …

…enable_search is false (#1299)

cmd/main.go

@@ -34,6 +34,7 @@ import (
 	"github.com/datacommonsorg/mixer/internal/server/resource"
 	"github.com/datacommonsorg/mixer/internal/sqldb"
 	"github.com/datacommonsorg/mixer/internal/sqldb/cloudsql"
+	"github.com/datacommonsorg/mixer/internal/sqldb/query"
 	"github.com/datacommonsorg/mixer/internal/sqldb/sqlite"
 	"github.com/datacommonsorg/mixer/internal/store"
 	"github.com/datacommonsorg/mixer/internal/store/bigtable"
@@ -224,7 +225,7 @@ func main() {
 	}
 	// Build the cache that includes stat var group info and stat var search
 	// Index.
-	var c *resource.Cache
+	c := &resource.Cache{}
 	if *useSearch {
 		c, err = cache.NewCache(
 			ctx, store,
@@ -237,6 +238,13 @@ func main() {
 			log.Fatalf("Failed to create cache: %v", err)
 		}
 	}
+	if store.SQLClient != nil {
+		customProv, err := query.GetProvenances(store.SQLClient)
+		if err != nil {
+			log.Fatalf("Failed to get provenance from SQL database: %s", err)
+		}
+		c.CustomProvenances = customProv
+	}
 
 	// Maps client
 	var mapsClient *maps.Client

internal/server/cache/cache.go

@@ -22,7 +22,6 @@ import (
 
 	"github.com/datacommonsorg/mixer/internal/server/resource"
 	"github.com/datacommonsorg/mixer/internal/server/statvar"
-	"github.com/datacommonsorg/mixer/internal/sqldb/query"
 	"github.com/datacommonsorg/mixer/internal/store"
 )
 
@@ -72,12 +71,5 @@ func NewCache(
 			result.SvgSearchIndex = statvar.BuildStatVarSearchIndex(rawSvg, parentSvgMap, blocklistSvg)
 		}
 	}
-	if store.SQLClient != nil {
-		customProv, err := query.GetProvenances(store.SQLClient)
-		if err != nil {
-			return nil, err
-		}
-		result.CustomProvenances = customProv
-	}
 	return result, nil
 }