feat(scale-out): use gqlparser for parsing incoming query

Signed-off-by: Vishwas Rajashekar <vrajashe@cisco.com>

examples/scale-out-cluster-local/config-cluster-member0.json

@@ -1,7 +1,7 @@
 {
   "distSpecVersion": "1.1.0",
   "storage": {
-    "rootDirectory": "/tmp/zot0",
+    "rootDirectory": "/workspace/zot/data/mem1",
     "dedupe": false
   },
   "http": {

examples/scale-out-cluster-local/config-cluster-member1.json

@@ -1,7 +1,7 @@
 {
   "distSpecVersion": "1.1.0",
   "storage": {
-    "rootDirectory": "/tmp/zot1",
+    "rootDirectory": "/workspace/zot/data/mem2",
     "dedupe": false
   },
   "http": {

pkg/extensions/extension_search.go

@@ -92,17 +92,18 @@ func SetupSearchRoutes(conf *config.Config, router *mux.Router, storeController
 	}
 
 	resConfig := search.GetResolverConfig(log, storeController, metaDB, cveInfo)
+	executableSchema := gql_generated.NewExecutableSchema(resConfig)
 
 	allowedMethods := zcommon.AllowedMethods(http.MethodGet, http.MethodPost)
 
-	gqlProxy := gqlproxy.GqlProxyRequestHandler(conf, log)
+	gqlProxy := gqlproxy.GqlProxyRequestHandler(conf, log, executableSchema.Schema())
 
 	extRouter := router.PathPrefix(constants.ExtSearchPrefix).Subrouter()
 	extRouter.Use(zcommon.CORSHeadersMiddleware(conf.HTTP.AllowOrigin))
 	extRouter.Use(zcommon.ACHeadersMiddleware(conf, allowedMethods...))
 	extRouter.Use(zcommon.AddExtensionSecurityHeaders())
 	extRouter.Methods(allowedMethods...).
-		Handler(gqlProxy(gqlHandler.NewDefaultServer(gql_generated.NewExecutableSchema(resConfig))))
+		Handler(gqlProxy(gqlHandler.NewDefaultServer(executableSchema)))
 
 	log.Info().Msg("finished setting up search routes")
 }

pkg/extensions/search/gql_proxy/global_search_handler.go

@@ -96,7 +96,7 @@ func HandleGlobalSearchResult(
 		)
 	}
 
-	responseBody, err := json.Marshal(collatedResult)
+	responseBody, err := json.MarshalIndent(collatedResult, "", "    ")
 	if err != nil {
 		log.Error().
 			Str(LoggerFieldOperation, HandlerOperation).
@@ -106,6 +106,8 @@ func HandleGlobalSearchResult(
 		return
 	}
 
+	response.Header().Set("Content-Type", "application/json")
+
 	_, err = response.Write(responseBody)
 	if err != nil {
 		log.Error().

pkg/extensions/search/gql_proxy/gql_proxy.go

@@ -2,7 +2,9 @@ package gqlproxy
 
 import (
 	"net/http"
-	"strings"
+
+	"github.com/vektah/gqlparser/v2"
+	"github.com/vektah/gqlparser/v2/ast"
 
 	"zotregistry.dev/zot/pkg/api/config"
 	"zotregistry.dev/zot/pkg/api/constants"
@@ -14,7 +16,11 @@ import (
 // Requests are only proxied in local cluster mode as in this mode, each instance holds only the
 // metadata for the images that it serves, however, in shared storage mode,
 // all the instances have access to all the metadata so any can respond.
-func GqlProxyRequestHandler(config *config.Config, log log.Logger) func(handler http.Handler) http.Handler {
+func GqlProxyRequestHandler(
+	config *config.Config,
+	log log.Logger,
+	gqlSchema *ast.Schema,
+) func(handler http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
 			// If not running in cluster mode, no op.
@@ -37,28 +43,40 @@ func GqlProxyRequestHandler(config *config.Config, log log.Logger) func(handler
 				return
 			}
 
-			// General Structure for GQL Requests
-			// Query String contains the full GraphQL Request (it's NOT JSON)
-			// e.g. {(query:"", requestedPage: {limit:3 offset:0 sortBy: DOWNLOADS} )
-			// {Page {TotalCount ItemCount} Repos {Name LastUpdated Size Platforms { Os Arch }
-			// IsStarred IsBookmarked NewestImage { Tag Vulnerabilities {MaxSeverity Count}
-			// Description IsSigned SignGlobalSearchatureInfo { Tool IsTrusted Author } Licenses Vendor Labels }
-			// StarCount DownloadCount}}}
-
-			// General Payload Structure for GQL Response
-			/*
-				{
-					"errors": [CUSTOM_ERRORS_HERE],
-					"data": {
-						"NameOfQuery": {CUSTOM_SCHEMA_HERE}
-					}
-				}
-			*/
-
 			query := request.URL.Query().Get("query")
 
-			operation, ok := computeGqlOperation(query)
-			if !ok {
+			// Load the query using gqlparser.
+			// This helps to read the Operation correctly which is in turn used to
+			// dynamically hand-off the processing to the appropriate handler.
+			processedGql, errList := gqlparser.LoadQuery(gqlSchema, query)
+
+			if len(errList) != 0 {
+				for _, err := range errList {
+					log.Error().Str("query", query).Err(err).Msg(err.Message)
+				}
+				http.Error(response, "Failed to process GQL request", http.StatusInternalServerError)
+
+				return
+			}
+
+			// Look at the first operation in the query.
+			// TODO: for completeness, this should support multiple
+			// operations at once.
+			operation := ""
+			for _, op := range processedGql.Operations {
+				for _, ss := range op.SelectionSet {
+					switch ss := ss.(type) {
+					case *ast.Field:
+						operation = ss.Name
+					default:
+						log.Error().Str("query", query).Msg("Unsupported type")
+					}
+
+					break
+				}
+			}
+
+			if operation == "" {
 				log.Error().Str("query", query).Msg("Failed to compute operation from query")
 				http.Error(response, "Failed to process GQL request", http.StatusInternalServerError)
 
@@ -80,16 +98,3 @@ func GqlProxyRequestHandler(config *config.Config, log log.Logger) func(handler
 		})
 	}
 }
-
-// Naively compute which operation is requested for GQL.
-// TODO: Need to replace this with better custom GQL parsing
-// or a parsing library that can conver the GQL query to
-// a struct where operations data and schema are available for reading.
-func computeGqlOperation(request string) (string, bool) {
-	openParenthesisIndex := strings.Index(request, "(")
-	if openParenthesisIndex == -1 {
-		return "", false
-	}
-
-	return request[1:openParenthesisIndex], true
-}

pkg/extensions/search/search_test.go

@@ -3916,7 +3916,6 @@ func TestGlobalSearch(t *testing.T) {
 }
 
 func TestGlobalSearchWithScaleOutProxyLocalStorage(t *testing.T) {
-
 	// When there are 2 zot instances, the same GlobalSearch query should
 	// return aggregated data from both instances when both instances are queried.
 	Convey("In a local scale-out cluster with 2 members, should return correct data for GlobalSearch", t, func() {