js-differ

A JavaScript library for get and apply diffs for JSON data values.

Installation

npm install js-differ

API

Types

type Path = (string | number)[]
 
type CheckFunction = (from: any, to: any, path: Path) => boolean;
 
type GetCustomParamsFunction = (from: any, to: any, path: Path, getDiff: (from: any, to: any, path: Path) => Diff) => any;
 
type CustomHandlerFunction = (value: any, customParams: any, path: Path, apply: (value: any, diff: Diff, path: Path) => any) => any;

Methods

getDiff(from, to, options)

Returns structure of diff to pass in applyDiff functon.

Param	Type	Required	Description
from	any	+	Initial value.
to	any	+	Result value.
options	object	-	More info here.

applyDiff(value, diff, options)

Returns new value by applying diff to initial value.

Param	Type	Required	Description
value	any	+	Initial value.
diff	object	+	Result of getDiff function.
options	object	-	More info here.

isEqualDefault(from, to, path)

isRemoveDefault(from, to, path)

isReplaceDefault(from, to, path)

Options

Get Diff Options

Option	Type	Default Value	Description
isEqual	CheckFunction	isEqualDefault	You can customize isEqual function. Priority 0.
isRemove	CheckFunction	isRemoveDefault	You can customize isRemove function. Priority 1.
isReplace	CheckFunction	isReplaceDefault	You can customize isReplace function. Priority 2.
isCustom	CheckFunction	-	You can specify your custom behaviour of diff. If you implement this function you must implement getCustomParams too. Also implement customHandler function of Apply Diff Options
getCustomParams	GetCustomParamsFunction	-	Custom params getter.
customDiffPriority	number	3	Priority of isCustom check (by default is after repalce). Available values are 0, 1, 2, 3, 4

Apply Diff Options

Option	Type	Required	Description
customHandler	CustomHandlerFunction	-	If isCustom was implemented in Get Diff Options you should implement this funciton. customParams is a result of getCustomParams