feat(GraphQL): @custom HTTP body now supports hardcoded scalars

graphql/e2e/custom_logic/cmd/main.go

@@ -281,7 +281,7 @@ func postFavMoviesWithBodyHandler(w http.ResponseWriter, r *http.Request) {
 	err := verifyRequest(r, expectedRequest{
 		method:    http.MethodPost,
 		urlSuffix: "/0x123?name=Author",
-		body:      `{"id":"0x123","name":"Author"}`,
+		body:      `{"id":"0x123","movie_type":"space","name":"Author"}`,
 		headers:   nil,
 	})
 	if err != nil {

graphql/e2e/custom_logic/custom_logic_test.go

@@ -165,7 +165,7 @@ func TestCustomPostQueryWithBody(t *testing.T) {
 	 type Query {
 		 myFavoriteMoviesPost(id: ID!, name: String!, num: Int): [Movie] @custom(http: {
 				 url: "http://mock:8888/favMoviesPostWithBody/$id?name=$name",
-                 body:"{id:$id,name:$name,num:$num}"
+                 body:"{id:$id,name:$name,num:$num,movie_type:\"space\"}"
 				 method: "POST"
 		 })
 	 }`

graphql/resolve/resolver.go

@@ -852,13 +852,7 @@ func resolveCustomField(f schema.Field, vals []interface{}, mu *sync.RWMutex, er
 			}
 
 			mu.RLock()
-			if err := schema.SubstituteVarsInBody(&temp, vals[i].(map[string]interface{})); err != nil {
-				errCh <- x.GqlErrorf("Evaluation of custom field failed while substituting "+
-					"variables into body for remote endpoint with an error: %s for field: %s "+
-					"within type: %s.", err, f.Name(), f.GetObjectName()).WithLocations(f.Location())
-				mu.RUnlock()
-				return
-			}
+			schema.SubstituteVarsInBody(&temp, vals[i].(map[string]interface{}))
 			mu.RUnlock()
 			inputs[i] = temp
 		}

graphql/schema/gqlschema_test.yml

@@ -1175,11 +1175,11 @@ invalid_schemas:
         getAuthor1(id: ID): Author! @custom(http: {
           url: "http://google.com/",
           method: "POST",
-          body: "{id: $id, name: \"name\"}",
+          body: "{id: $id, name: name}",
         })
       }
     errlist: [
-    {"message": "Type Query; Field getAuthor1; body template inside @custom directive could not be parsed.",
+    {"message": "Type Query; Field getAuthor1; body template inside @custom directive could not be parsed: found unexpected value: name",
      "locations":[{"line":10, "column":12}]},
     ]
 
@@ -2636,7 +2636,7 @@ valid_schemas:
       }
 
   -
-    name: "Query, Mutation in initial schema with @custom directive"
+    name: "initial schema with @custom directive"
     input: |
       type Author {
         id: ID!
@@ -2645,9 +2645,25 @@ valid_schemas:
       input AuthorUpdate {
         id: ID!
       }
+      type Country {
+        country_code: String! @id
+        authors: [Author] @custom(http: {
+             url: "http://blah.com",
+             method: "POST"
+             graphql: "query ($input: [AuthorInput]) { authors(input: $input) }"
+             body: "{country_code: $country_code, version: ONE}"
+             mode: BATCH
+             skipIntrospection: true
+        })
+      }
 
       type Query {
         getMyAuthor(id: ID): Author! @custom(http: {url: "http://blah.com", method: "GET"})
+        getAuthorsForCountry(country_code: String!): [Author] @custom(http: {
+            url: "http://blah.com"
+            method: "POST"
+            body: "{country_code: $country_code, version: 1, tag: \"temp\"}"
+        })
       }
       type Mutation {
         updateMyAuthor(input: AuthorUpdate!): Author! @custom(http: {url: "http://blah.com",

graphql/schema/rules.go

@@ -1418,11 +1418,11 @@ func customDirectiveValidation(sch *ast.Schema,
 	// 8. Validating body
 	var requiredFields map[string]bool
 	if body != nil {
-		_, requiredFields, err = parseBodyTemplate(body.Raw)
+		_, requiredFields, err = parseBodyTemplate(body.Raw, graphql == nil)
 		if err != nil {
 			errs = append(errs, gqlerror.ErrorPosf(body.Position,
-				"Type %s; Field %s; body template inside @custom directive could not be parsed.",
-				typ.Name, field.Name))
+				"Type %s; Field %s; body template inside @custom directive could not be parsed: %s",
+				typ.Name, field.Name, err.Error()))
 		}
 		// Validating params to body template for Query/Mutation types. For other types the
 		// validation is performed later along with graphql.
@@ -1564,7 +1564,7 @@ func customDirectiveValidation(sch *ast.Schema,
 					bodyBuilder.WriteString(comma)
 				}
 				bodyBuilder.WriteString("}")
-				_, requiredVars, err := parseBodyTemplate(bodyBuilder.String())
+				_, requiredVars, err := parseBodyTemplate(bodyBuilder.String(), false)
 				if err != nil {
 					errs = append(errs, gqlerror.ErrorPosf(graphql.Position,
 						"Type %s; Field %s: inside graphql in @custom directive, "+