Optimizations to improve performance on complex conditional schemas

packages/core/src/utils.js

@@ -1,13 +1,16 @@
 import React from "react";
 import * as ReactIs from "react-is";
-import mergeAllOf from "json-schema-merge-allof";
 import fill from "core-js-pure/features/array/fill";
 import union from "lodash/union";
 import jsonpointer from "jsonpointer";
 import fields from "./components/fields";
 import widgets from "./components/widgets";
 import validateFormData, { isValid } from "./validate";
+import _ from "lodash";
 
+// Use the same default object to optimize memoized functions that rely on referential equality
+const DEFAULT_ROOT_SCHEMA = {};
+const DEFAULT_FORM_DATA = {};
 export const ADDITIONAL_PROPERTY_FLAG = "__additional_property";
 
 const widgetMap = {
@@ -171,11 +174,14 @@ export function hasWidget(schema, widget, registeredWidgets = {}) {
   }
 }
 
-function computeDefaults(
+const cacheKeyFn = (...args) => args.map(arg => JSON.stringify(arg)).join("_");
+const computeDefaults = _.memoize(_computeDefaults, cacheKeyFn);
+
+function _computeDefaults(
   _schema,
   parentDefaults,
   rootSchema,
-  rawFormData = {},
+  rawFormData = DEFAULT_FORM_DATA,
   includeUndefinedValues = false
 ) {
   let schema = isObject(_schema) ? _schema : {};
@@ -303,7 +309,7 @@ function computeDefaults(
 export function getDefaultFormState(
   _schema,
   formData,
-  rootSchema = {},
+  rootSchema = DEFAULT_ROOT_SCHEMA,
   includeUndefinedValues = false
 ) {
   if (!isObject(_schema)) {
@@ -521,7 +527,7 @@ export function toConstant(schema) {
   }
 }
 
-export function isSelect(_schema, rootSchema = {}) {
+export function isSelect(_schema, rootSchema = DEFAULT_ROOT_SCHEMA) {
   const schema = retrieveSchema(_schema, rootSchema);
   const altSchemas = schema.oneOf || schema.anyOf;
   if (Array.isArray(schema.enum)) {
@@ -532,14 +538,18 @@ export function isSelect(_schema, rootSchema = {}) {
   return false;
 }
 
-export function isMultiSelect(schema, rootSchema = {}) {
+export function isMultiSelect(schema, rootSchema = DEFAULT_ROOT_SCHEMA) {
   if (!schema.uniqueItems || !schema.items) {
     return false;
   }
   return isSelect(schema.items, rootSchema);
 }
 
-export function isFilesArray(schema, uiSchema, rootSchema = {}) {
+export function isFilesArray(
+  schema,
+  uiSchema,
+  rootSchema = DEFAULT_ROOT_SCHEMA
+) {
   if (uiSchema["ui:widget"] === "files") {
     return true;
   } else if (schema.items) {
@@ -584,7 +594,7 @@ export function optionsList(schema) {
   }
 }
 
-export function findSchemaDefinition($ref, rootSchema = {}) {
+export function findSchemaDefinition($ref, rootSchema = DEFAULT_ROOT_SCHEMA) {
   const origRef = $ref;
   if ($ref.startsWith("#")) {
     // Decode URI fragment representation.
@@ -625,8 +635,8 @@ export const guessType = function guessType(value) {
 // This function will create new "properties" items for each key in our formData
 export function stubExistingAdditionalProperties(
   schema,
-  rootSchema = {},
-  formData = {}
+  rootSchema = DEFAULT_ROOT_SCHEMA,
+  formData = DEFAULT_FORM_DATA
 ) {
   // Clone the schema so we don't ruin the consumer's original
   schema = {
@@ -662,21 +672,28 @@ export function stubExistingAdditionalProperties(
   return schema;
 }
 
-export function resolveSchema(schema, rootSchema = {}, formData = {}) {
+export const resolveSchema = _.memoize(_resolveSchema, cacheKeyFn);
+
+export function _resolveSchema(
+  schema,
+  rootSchema = DEFAULT_ROOT_SCHEMA,
+  formData = DEFAULT_FORM_DATA
+) {
   if (schema.hasOwnProperty("$ref")) {
     return resolveReference(schema, rootSchema, formData);
   } else if (schema.hasOwnProperty("dependencies")) {
     const resolvedSchema = resolveDependencies(schema, rootSchema, formData);
     return retrieveSchema(resolvedSchema, rootSchema, formData);
-  } else if (schema.hasOwnProperty("allOf")) {
+  } else if (schema["allOf"]) {
     return {
       ...schema,
       allOf: schema.allOf.map(allOfSubschema =>
         retrieveSchema(allOfSubschema, rootSchema, formData)
       ),
     };
   } else {
-    // No $ref or dependencies attribute found, returning the original schema.
+    // No $ref, dependencies, or allOf attribute found, so there's nothing to resolve.
+    // Returning the original schema.
     return schema;
   }
 }
@@ -694,45 +711,40 @@ function resolveReference(schema, rootSchema, formData) {
   );
 }
 
-export function retrieveSchema(schema, rootSchema = {}, formData = {}) {
+export function _retrieveSchema(
+  schema,
+  rootSchema = DEFAULT_ROOT_SCHEMA,
+  formData = DEFAULT_FORM_DATA
+) {
   if (!isObject(schema)) {
-    return {};
+    return DEFAULT_ROOT_SCHEMA;
   }
   let resolvedSchema = resolveSchema(schema, rootSchema, formData);
 
-  const hasAdditionalProperties =
-    resolvedSchema.hasOwnProperty("additionalProperties") &&
-    resolvedSchema.additionalProperties !== false;
-
-  if (hasAdditionalProperties) {
-    resolvedSchema = stubExistingAdditionalProperties(
-      resolvedSchema,
-      rootSchema,
-      formData
-    );
-  }
-
-  if ("if" in resolvedSchema) {
+  while ("if" in resolvedSchema) {
     // Note that if and else are key words in javascript so extract to variable names which are allowed
     var {
       if: expression,
       then,
       else: otherwise,
       ...resolvedSchemaLessConditional
     } = resolvedSchema;
-    var conditionalSchema = isValid(expression, formData) ? then : otherwise;
+
+    var conditionalSchema = isValid(expression, formData, rootSchema)
+      ? then
+      : otherwise;
 
     if (conditionalSchema) {
       conditionalSchema = resolveSchema(
         conditionalSchema,
         rootSchema,
         formData
       );
-      resolvedSchema = mergeSchemas(
-        resolvedSchemaLessConditional,
-        conditionalSchema
-      );
     }
+    resolvedSchema = mergeSchemas(
+      resolvedSchemaLessConditional,
+      conditionalSchema || {}
+    );
   }
 
   let allOf = resolvedSchema.allOf;
@@ -743,22 +755,38 @@ export function retrieveSchema(schema, rootSchema = {}, formData = {}) {
 
       // if we see an if in our all of schema then evaluate the if schema and select the then / else, not sure if we should still merge without our if then else
       if ("if" in allOfSchema) {
-        allOfSchema = isValid(allOfSchema.if, formData)
+        allOfSchema = isValid(allOfSchema.if, formData, rootSchema)
           ? allOfSchema.then
           : allOfSchema.else;
       }
 
       if (allOfSchema) {
         allOfSchema = resolveSchema(allOfSchema, rootSchema, formData); // resolve references etc.
-        resolvedSchema = mergeSchemas(resolvedSchema, allOfSchema);
-        delete resolvedSchema.allOf;
+        resolvedSchema = {
+          ...mergeSchemas(resolvedSchema, allOfSchema),
+          allOf: undefined,
+        };
       }
     }
   }
 
+  const hasAdditionalProperties =
+    resolvedSchema.hasOwnProperty("additionalProperties") &&
+    resolvedSchema.additionalProperties !== false;
+
+  if (hasAdditionalProperties) {
+    resolvedSchema = stubExistingAdditionalProperties(
+      resolvedSchema,
+      rootSchema,
+      formData
+    );
+  }
+
   return resolvedSchema;
 }
 
+export const retrieveSchema = _.memoize(_retrieveSchema, cacheKeyFn);
+
 function resolveDependencies(schema, rootSchema, formData) {
   // Drop the dependencies from the source schema.
   let { dependencies = {}, ...resolvedSchema } = schema;
@@ -1029,7 +1057,7 @@ export function toIdSchema(
   schema,
   id,
   rootSchema,
-  formData = {},
+  formData = DEFAULT_FORM_DATA,
   idPrefix = "root"
 ) {
   const idSchema = {
@@ -1061,7 +1089,12 @@ export function toIdSchema(
   return idSchema;
 }
 
-export function toPathSchema(schema, name = "", rootSchema, formData = {}) {
+export function toPathSchema(
+  schema,
+  name = "",
+  rootSchema,
+  formData = DEFAULT_FORM_DATA
+) {
   const pathSchema = {
     $name: name.replace(/^\./, ""),
   };