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A JavaScript implementation of the JSON Object Notation (JSON) Patch and JSON Pointer specifications.


Library to apply JSON Patches in JavaScript

jsonpatch-js works as in the browser as a script, as a Node module and as an AMD module.


bower install json-patch


npm install json-patch

Note: at this time, all operations are applied in-place.

jsonpatch.apply(document, patch)

Applies a patch to the document


Compiles a patch and returns a function that takes a document to apply the patch to.

Patch syntax: {op: 'add', path: <path>, value: <value>}

// Add property, result: {foo: 'bar'} 
jsonpatch.apply({}, [{op: 'add', path: '/foo', value: 'bar'}]);
// Add array element, result: {foo: [1, 2, 3]} 
jsonpatch.apply({foo: [1, 3]}, [{op: 'add', path: '/foo/1', value: 2}]);
// Complex, result: {foo: [{bar: 'baz'}]} 
jsonpatch.apply({foo: [{}]}, [{op: 'add', path: '/foo/0/bar', value: 'baz'}]);

Patch syntax: {op: 'remove', path: <path>}

// Remove property, result: {} 
jsonpatch.apply({foo: 'bar'}, [{op: 'remove', path: '/foo'}]);
// Remove array element, result: {foo: [1, 3]} 
jsonpatch.apply({foo: [1, 2, 3]}, [{op: 'remove', path: '/foo/1'}]);
// Complex, result: {foo: [{}]} 
jsonpatch.apply({foo: [{bar: 'baz'}]}, [{op: 'remove', path: '/foo/0/bar'}]);

Patch syntax: {op: 'replace', path: <path>, value: <value>}

// Replace property, result: {foo: 1} 
jsonpatch.apply({foo: 'bar'}, [{op: 'replace', path: '/foo', value: 1}]);
// Replace array element, result: {foo: [1, 4, 3]} 
jsonpatch.apply({foo: [1, 2, 3]}, [{op: 'replace', path: '/foo/1', value: 4}]);
// Complex, result: {foo: [{bar: 1}]} 
jsonpatch.apply({foo: [{bar: 'baz'}]}, [{op: 'replace', path: '/foo/0/bar', value: 1}]);

Patch syntax: {op: 'move', from: <path>, path: <path>}

// Move property, result {bar: [1, 2, 3]} 
jsonpatch.apply({foo: [1, 2, 3]}, [{op: 'move', from: '/foo', path: '/bar'}]);

Patch syntax: {op: 'copy', from: <path>, path: <path>}

// Copy property, result {foo: [1, 2, 3], bar: 2} 
jsonpatch.apply({foo: [1, 2, 3]}, [{op: 'copy', from: '/foo/1', path: '/bar'}]);

Patch syntax: {op: 'test', path: <path>, value: <value>}

// Test equality of property to value, result: true 
jsonpatch.apply({foo: 'bar'}, [{op: 'test', path: '/foo', value: 'bar'}]

Changed in 0.5.0

The return value is no longer a boolean, but now the the document itself which adheres correctly to the specification. It the test fails, a PatchTestFailed error will be thrown.


Base error type which all patch errors extend from.


Thrown when the pointer is invalid.


Thrown when the patch itself has an invalid syntax.


Thrown when there is a conflic with applying the patch to the document.


Thrown when a test operation is applied and fails.