experimental_customMergeAllOf

CHANGELOG.md

@@ -23,6 +23,10 @@ should change the heading of the (upcoming) version to include a major version b
 - Updated `SchemaField` to pass `required` flag to `_AnyOfField`/`_OneOfField`
 - Updated `Form` to deal with null objects in `filterErrorsBasedOnSchema()`, fixing [#4306](https://github.com/rjsf-team/react-jsonschema-form/issues/4306)
 
+## @rjsf/utils
+
+- Added `experimental_customMergeAllOf` option to `retrieveSchema` to allow custom merging of `allOf` schemas
+
 ## Dev / docs / playground
 
 - Updated the `custom-widgets-fields.md` to add examples of wrapping a widget/field

packages/core/src/components/Form.tsx

@@ -33,6 +33,7 @@ import {
   validationDataMerge,
   ValidatorType,
   Experimental_DefaultFormStateBehavior,
+  Experimental_CustomMergeAllOf,
 } from '@rjsf/utils';
 import _forEach from 'lodash/forEach';
 import _get from 'lodash/get';
@@ -196,6 +197,9 @@ export interface FormProps<T = any, S extends StrictRJSFSchema = RJSFSchema, F e
    * `emptyObjectFields`
    */
   experimental_defaultFormStateBehavior?: Experimental_DefaultFormStateBehavior;
+  /** Optional function that allows for custom merging of `allOf` schemas
+   */
+  experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>;
   // Private
   /**
    * _internalFormWrapper is currently used by the semantic-ui theme to provide a custom wrapper around `<Form />`
@@ -390,12 +394,26 @@ export default class Form<
       'experimental_defaultFormStateBehavior' in props
         ? props.experimental_defaultFormStateBehavior
         : this.props.experimental_defaultFormStateBehavior;
+    const experimental_customMergeAllOf =
+      'experimental_customMergeAllOf' in props
+        ? props.experimental_customMergeAllOf
+        : this.props.experimental_customMergeAllOf;
     let schemaUtils: SchemaUtilsType<T, S, F> = state.schemaUtils;
     if (
       !schemaUtils ||
-      schemaUtils.doesSchemaUtilsDiffer(props.validator, rootSchema, experimental_defaultFormStateBehavior)
+      schemaUtils.doesSchemaUtilsDiffer(
+        props.validator,
+        rootSchema,
+        experimental_defaultFormStateBehavior,
+        experimental_customMergeAllOf
+      )
     ) {
-      schemaUtils = createSchemaUtils<T, S, F>(props.validator, rootSchema, experimental_defaultFormStateBehavior);
+      schemaUtils = createSchemaUtils<T, S, F>(
+        props.validator,
+        rootSchema,
+        experimental_defaultFormStateBehavior,
+        experimental_customMergeAllOf
+      );
     }
     const formData: T = schemaUtils.getDefaultFormState(schema, inputFormData) as T;
     const _retrievedSchema = retrievedSchema ?? schemaUtils.retrieveSchema(schema, formData);

packages/docs/docs/api-reference/form-props.md

@@ -91,8 +91,8 @@ The signature and documentation for this property is as follow:
 ##### computeSkipPopulate <T = any, S extends StrictRJSFSchema = RJSFSchema, F extends FormContextType = any>()
 
 A function that determines whether to skip populating the array with default values based on the provided validator, schema, and root schema.
- If the function returns `true`, the array will not be populated with default values.
- If the function returns `false`, the array will be populated with default values according to the `populate` option.
+If the function returns `true`, the array will not be populated with default values.
+If the function returns `false`, the array will be populated with default values according to the `populate` option.
 
 ###### Parameters
 
@@ -104,7 +104,6 @@ A function that determines whether to skip populating the array with default val
 
 - boolean: A boolean indicating whether to skip populating the array with default values.
 
-
 ##### Example
 
 ```tsx
@@ -252,6 +251,30 @@ render(
 );
 ```
 
+## experimental_customMergeAllOf
+
+The `experimental_customMergeAllOf` function allows you to provide a custom implementation for merging `allOf` schemas. This can be particularly useful in scenarios where the default [json-schema-merge-allof](https://github.com/mokkabonna/json-schema-merge-allof) library becomes a performance bottleneck, especially with large and complex schemas or doesn't satisfy your needs.
+
+By providing your own implementation, you can potentially achieve significant performance improvements. For instance, if your use case only requires a subset of JSON Schema features, you can implement a faster, more tailored merging strategy.
+
+If you're looking for alternative `allOf` merging implementations, you might consider [allof-merge](https://github.com/udamir/allof-merge).
+
+**Warning:** This is an experimental feature. Only use this if you fully understand the implications of custom `allOf` merging and are prepared to handle potential edge cases. Incorrect implementations may lead to unexpected behavior or validation errors.
+
+```tsx
+import { Form } from '@rjsf/core';
+import validator from '@rjsf/validator-ajv8';
+
+const customMergeAllOf = (schema: RJSFSchema): RJSFSchema => {
+  // Your custom implementation here
+};
+
+render(
+  <Form schema={schema} validator={validator} experimental_customMergeAllOf={customMergeAllOf} />,
+  document.getElementById('app')
+);
+```
+
 ## disabled
 
 It's possible to disable the whole form by setting the `disabled` prop. The `disabled` prop is then forwarded down to each field of the form.

packages/utils/src/createSchemaUtils.ts

@@ -1,6 +1,7 @@
 import deepEquals from './deepEquals';
 import {
   ErrorSchema,
+  Experimental_CustomMergeAllOf,
   Experimental_DefaultFormStateBehavior,
   FormContextType,
   GlobalUISchemaOptions,
@@ -30,31 +31,36 @@ import {
 } from './schema';
 
 /** The `SchemaUtils` class provides a wrapper around the publicly exported APIs in the `utils/schema` directory such
- * that one does not have to explicitly pass the `validator`, `rootSchema`, or `experimental_defaultFormStateBehavior` to each method.
- * Since these generally do not change across a `Form`, this allows for providing a simplified set of APIs to the
- * `@rjsf/core` components and the various themes as well. This class implements the `SchemaUtilsType` interface.
+ * that one does not have to explicitly pass the `validator`, `rootSchema`, `experimental_defaultFormStateBehavior` or
+ * `experimental_customMergeAllOf` to each method. Since these generally do not change across a `Form`, this allows for
+ * providing a simplified set of APIs to the `@rjsf/core` components and the various themes as well. This class
+ * implements the `SchemaUtilsType` interface.
  */
 class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends FormContextType = any>
   implements SchemaUtilsType<T, S, F>
 {
   rootSchema: S;
   validator: ValidatorType<T, S, F>;
   experimental_defaultFormStateBehavior: Experimental_DefaultFormStateBehavior;
+  experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>;
 
   /** Constructs the `SchemaUtils` instance with the given `validator` and `rootSchema` stored as instance variables
    *
    * @param validator - An implementation of the `ValidatorType` interface that will be forwarded to all the APIs
    * @param rootSchema - The root schema that will be forwarded to all the APIs
    * @param experimental_defaultFormStateBehavior - Configuration flags to allow users to override default form state behavior
+   * @param [experimental_customMergeAllOf] - Optional function that allows for custom merging of `allOf` schemas
    */
   constructor(
     validator: ValidatorType<T, S, F>,
     rootSchema: S,
-    experimental_defaultFormStateBehavior: Experimental_DefaultFormStateBehavior
+    experimental_defaultFormStateBehavior: Experimental_DefaultFormStateBehavior,
+    experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>
   ) {
     this.rootSchema = rootSchema;
     this.validator = validator;
     this.experimental_defaultFormStateBehavior = experimental_defaultFormStateBehavior;
+    this.experimental_customMergeAllOf = experimental_customMergeAllOf;
   }
 
   /** Returns the `ValidatorType` in the `SchemaUtilsType`
@@ -72,20 +78,23 @@ class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends Fo
    * @param validator - An implementation of the `ValidatorType` interface that will be compared against the current one
    * @param rootSchema - The root schema that will be compared against the current one
    * @param [experimental_defaultFormStateBehavior] Optional configuration object, if provided, allows users to override default form state behavior
+   * @param [experimental_customMergeAllOf] - Optional function that allows for custom merging of `allOf` schemas
    * @returns - True if the `SchemaUtilsType` differs from the given `validator` or `rootSchema`
    */
   doesSchemaUtilsDiffer(
     validator: ValidatorType<T, S, F>,
     rootSchema: S,
-    experimental_defaultFormStateBehavior = {}
+    experimental_defaultFormStateBehavior = {},
+    experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>
   ): boolean {
     if (!validator || !rootSchema) {
       return false;
     }
     return (
       this.validator !== validator ||
       !deepEquals(this.rootSchema, rootSchema) ||
-      !deepEquals(this.experimental_defaultFormStateBehavior, experimental_defaultFormStateBehavior)
+      !deepEquals(this.experimental_defaultFormStateBehavior, experimental_defaultFormStateBehavior) ||
+      this.experimental_customMergeAllOf !== experimental_customMergeAllOf
     );
   }
 
@@ -110,7 +119,8 @@ class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends Fo
       formData,
       this.rootSchema,
       includeUndefinedValues,
-      this.experimental_defaultFormStateBehavior
+      this.experimental_defaultFormStateBehavior,
+      this.experimental_customMergeAllOf
     );
   }
 
@@ -234,7 +244,13 @@ class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends Fo
    * @returns - The schema having its conditions, additional properties, references and dependencies resolved
    */
   retrieveSchema(schema: S, rawFormData?: T) {
-    return retrieveSchema<T, S, F>(this.validator, schema, this.rootSchema, rawFormData);
+    return retrieveSchema<T, S, F>(
+      this.validator,
+      schema,
+      this.rootSchema,
+      rawFormData,
+      this.experimental_customMergeAllOf
+    );
   }
 
   /** Sanitize the `data` associated with the `oldSchema` so it is considered appropriate for the `newSchema`. If the
@@ -262,7 +278,16 @@ class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends Fo
    * @returns - The `IdSchema` object for the `schema`
    */
   toIdSchema(schema: S, id?: string | null, formData?: T, idPrefix = 'root', idSeparator = '_'): IdSchema<T> {
-    return toIdSchema<T, S, F>(this.validator, schema, id, this.rootSchema, formData, idPrefix, idSeparator);
+    return toIdSchema<T, S, F>(
+      this.validator,
+      schema,
+      id,
+      this.rootSchema,
+      formData,
+      idPrefix,
+      idSeparator,
+      this.experimental_customMergeAllOf
+    );
   }
 
   /** Generates an `PathSchema` object for the `schema`, recursively
@@ -283,6 +308,7 @@ class SchemaUtils<T = any, S extends StrictRJSFSchema = RJSFSchema, F extends Fo
  * @param validator - an implementation of the `ValidatorType` interface that will be forwarded to all the APIs
  * @param rootSchema - The root schema that will be forwarded to all the APIs
  * @param [experimental_defaultFormStateBehavior] Optional configuration object, if provided, allows users to override default form state behavior
+ * @param [experimental_customMergeAllOf] - Optional function that allows for custom merging of `allOf` schemas
  * @returns - An implementation of a `SchemaUtilsType` interface
  */
 export default function createSchemaUtils<
@@ -292,7 +318,13 @@ export default function createSchemaUtils<
 >(
   validator: ValidatorType<T, S, F>,
   rootSchema: S,
-  experimental_defaultFormStateBehavior = {}
+  experimental_defaultFormStateBehavior = {},
+  experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>
 ): SchemaUtilsType<T, S, F> {
-  return new SchemaUtils<T, S, F>(validator, rootSchema, experimental_defaultFormStateBehavior);
+  return new SchemaUtils<T, S, F>(
+    validator,
+    rootSchema,
+    experimental_defaultFormStateBehavior,
+    experimental_customMergeAllOf
+  );
 }

packages/utils/src/schema/getDefaultFormState.ts

@@ -20,6 +20,7 @@ import mergeDefaultsWithFormData from '../mergeDefaultsWithFormData';
 import mergeObjects from '../mergeObjects';
 import mergeSchemas from '../mergeSchemas';
 import {
+  Experimental_CustomMergeAllOf,
   Experimental_DefaultFormStateBehavior,
   FormContextType,
   GenericObjectType,
@@ -156,6 +157,8 @@ interface ComputeDefaultsProps<T = any, S extends StrictRJSFSchema = RJSFSchema>
   _recurseList?: string[];
   /** Optional configuration object, if provided, allows users to override default form state behavior */
   experimental_defaultFormStateBehavior?: Experimental_DefaultFormStateBehavior;
+  /** Optional function that allows for custom merging of `allOf` schemas */
+  experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>;
   /** Optional flag, if true, indicates this schema was required in the parent schema. */
   required?: boolean;
 }
@@ -180,6 +183,7 @@ export function computeDefaults<T = any, S extends StrictRJSFSchema = RJSFSchema
     includeUndefinedValues = false,
     _recurseList = [],
     experimental_defaultFormStateBehavior = undefined,
+    experimental_customMergeAllOf = undefined,
     required,
   } = computeDefaultsProps;
   const formData: T = (isObject(rawFormData) ? rawFormData : {}) as T;
@@ -209,7 +213,15 @@ export function computeDefaults<T = any, S extends StrictRJSFSchema = RJSFSchema
       ...formData,
       ...getDefaultBasedOnSchemaType(validator, schema, computeDefaultsProps, defaults),
     };
-    const resolvedSchema = resolveDependencies<T, S, F>(validator, schema, rootSchema, false, [], defaultFormData);
+    const resolvedSchema = resolveDependencies<T, S, F>(
+      validator,
+      schema,
+      rootSchema,
+      false,
+      [],
+      defaultFormData,
+      experimental_customMergeAllOf
+    );
     schemaToCompute = resolvedSchema[0]; // pick the first element from resolve dependencies
   } else if (isFixedItems(schema)) {
     defaults = (schema.items! as S[]).map((itemSchema: S, idx: number) =>
@@ -298,6 +310,7 @@ export function getObjectDefaults<T = any, S extends StrictRJSFSchema = RJSFSche
     includeUndefinedValues = false,
     _recurseList = [],
     experimental_defaultFormStateBehavior = undefined,
+    experimental_customMergeAllOf = undefined,
     required,
   }: ComputeDefaultsProps<T, S> = {},
   defaults?: T | T[] | undefined
@@ -309,7 +322,7 @@ export function getObjectDefaults<T = any, S extends StrictRJSFSchema = RJSFSche
     // https://github.com/rjsf-team/react-jsonschema-form/issues/3832
     const retrievedSchema =
       experimental_defaultFormStateBehavior?.allOf === 'populateDefaults' && ALL_OF_KEY in schema
-        ? retrieveSchema<T, S, F>(validator, schema, rootSchema, formData)
+        ? retrieveSchema<T, S, F>(validator, schema, rootSchema, formData, experimental_customMergeAllOf)
         : schema;
     const objectDefaults = Object.keys(retrievedSchema.properties || {}).reduce(
       (acc: GenericObjectType, key: string) => {
@@ -319,6 +332,7 @@ export function getObjectDefaults<T = any, S extends StrictRJSFSchema = RJSFSche
           rootSchema,
           _recurseList,
           experimental_defaultFormStateBehavior,
+          experimental_customMergeAllOf,
           includeUndefinedValues: includeUndefinedValues === true,
           parentDefaults: get(defaults, [key]),
           rawFormData: get(formData, [key]),
@@ -521,6 +535,7 @@ export function getDefaultBasedOnSchemaType<
  *          If "excludeObjectChildren", cause undefined values for this object and pass `includeUndefinedValues` as
  *          false when computing defaults for any nested object properties.
  * @param [experimental_defaultFormStateBehavior] Optional configuration object, if provided, allows users to override default form state behavior
+ * @param [experimental_customMergeAllOf] - Optional function that allows for custom merging of `allOf` schemas
  * @returns - The resulting `formData` with all the defaults provided
  */
 export default function getDefaultFormState<
@@ -533,16 +548,18 @@ export default function getDefaultFormState<
   formData?: T,
   rootSchema?: S,
   includeUndefinedValues: boolean | 'excludeObjectChildren' = false,
-  experimental_defaultFormStateBehavior?: Experimental_DefaultFormStateBehavior
+  experimental_defaultFormStateBehavior?: Experimental_DefaultFormStateBehavior,
+  experimental_customMergeAllOf?: Experimental_CustomMergeAllOf<S>
 ) {
   if (!isObject(theSchema)) {
     throw new Error('Invalid schema: ' + theSchema);
   }
-  const schema = retrieveSchema<T, S, F>(validator, theSchema, rootSchema, formData);
+  const schema = retrieveSchema<T, S, F>(validator, theSchema, rootSchema, formData, experimental_customMergeAllOf);
   const defaults = computeDefaults<T, S, F>(validator, schema, {
     rootSchema,
     includeUndefinedValues,
     experimental_defaultFormStateBehavior,
+    experimental_customMergeAllOf,
     rawFormData: formData,
   });
   if (formData === undefined || formData === null || (typeof formData === 'number' && isNaN(formData))) {