Registry / testing / json-schema-patch

json-schema-patch

library1.0.2jsnpmunverified

A library for dynamically modifying JSON Schema documents by applying add, remove, and replace operations on properties and definitions. Version 1.0.2 is the current stable release, with no frequent release cadence. Unlike manual schema manipulation, it automatically handles cleanup of $ref references when definitions are removed. Ships TypeScript types.

testing

npm install json-schema-patch

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · JSON-SCHEMA-PATCH

json-schema-patch

testingjavascriptv1.0.2

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

JSONSchemaPatch

✓ import { JSONSchemaPatch } from 'json-schema-patch'

✗ const JSONSchemaPatch = require('json-schema-patch')

ESM-only; CommonJS require is not supported.

PatchOperation

✓ import type { PatchOperation } from 'json-schema-patch'

✗ import { PatchOperation } from 'json-schema-patch'

Use type import for PatchOperation type as it is only a type.

JSONSchemaPatchOptions

✓ import type { JSONSchemaPatchOptions } from 'json-schema-patch'

✗ import { JSONSchemaPatchOptions } from 'json-schema-patch'

Options interface, type-only.

Demonstrates instantiation of JSONSchemaPatch, adding/removing definitions and properties, and applying the patch to modify the schema in place.

import { JSONSchemaPatch } from 'json-schema-patch'; const schema = { $defs: { asset: { type: 'object', properties: { id: { type: 'number' } } }, product: { type: 'object', properties: { name: { type: 'string' } } } }, properties: { name: { type: 'string' }, item: { allOf: [ { $ref: '#/$defs/asset' }, { $ref: '#/$defs/product' } ] }, equipment: { allOf: [ { $ref: '#/$defs/asset' } ] } }, required: ['name', 'item', 'equipment'] }; const patcher = new JSONSchemaPatch(schema); // Add a new definition patcher.addDefinition('newDef', { type: 'object', properties: { newProp: { type: 'string' } } }); // Remove a definition and clean up references patcher.removeDefinition('asset'); // Add a new property patcher.addProperty('/properties', 'newProp', { type: 'number' }); // Remove a property patcher.removeProperty('/properties', 'item'); // Apply all prepared operations and finalize changes patcher.applyPatch(); console.log(schema);

Debug

Known issues

breakingThe `applyPatch()` method mutates the original schema object passed to the constructor; it does not return a new copy.

fix

Clone the schema before passing it to JSONSchemaPatch if you need to preserve the original.

affects: >=1.0.0

gotchaOperations are queued until `applyPatch()` is called; calling accessors like `schema.properties` before applying will not reflect queued changes.

fix

Always call `applyPatch()` before reading the modified schema.

affects: >=1.0.0

gotchaThe `addProperty` path must start with a slash and refer to an existing object node; otherwise it may throw or cause unexpected behavior.

fix

Ensure the path is valid (e.g., '/properties') and the parent property exists.

affects: >=1.0.0

breakingRemoving a definition does not remove the $defs entry itself if there are still references; it only cleans up if references become zero after removal.

fix

Verify that no remaining $ref targets the definition after removal; otherwise it will persist.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: JSONSchemaPatch is not a constructor

Using CommonJS require instead of ESM import.

fix

Change const JSONSchemaPatch = require('json-schema-patch') to import { JSONSchemaPatch } from 'json-schema-patch'.

Cannot find module 'json-schema-patch'

Package not installed, or import path incorrect.

fix

Run npm install json-schema-patch and ensure import uses the correct package name.

Property 'addDefinition' does not exist on type 'JSONSchemaPatch'

Using TypeScript but not importing the type correctly, or using an older version without this method.

fix

Ensure you have version 1.0.0 or later, and import the class correctly: import { JSONSchemaPatch } from 'json-schema-patch'.

Cannot read properties of undefined (reading 'applyPatch')

JSONSchemaPatch was not instantiated (e.g., missing new keyword).

fix

Instantiate with new: const patcher = new JSONSchemaPatch(schema);

Upgrade

Version history

1.0.2latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/cosmology-tech/json-schema-patch ↗

packagejson-schema-patch ↗

homepagehttps://github.com/cosmology-tech/json-schema-patch#readme ↗