gulp-merge-json
A gulp plugin for deep-merging multiple JSON files into one file. Export as JSON or a node module.
Usage
gulp.src('jsonFiles/**/*.json')
.pipe(merge(options))
.pipe(gulp.dest('./dist'));Options
| Key | Type | Default | Description |
|---|---|---|---|
fileName |
String |
combined.json |
Output filename |
edit |
Function |
json => json |
Edit function (add/remove/edit keys during merge) |
transform |
Function |
json => json |
Transform final merged object (similar to edit but applied at the end) |
startObj |
Object/Array |
{} |
Starting object to merge into (useful for providing default values) |
endObj |
Object/Array |
Object to merge after file merging complete (useful for overwriting with special values) | |
exportModule |
Boolean/String |
false |
Output module.exports = {MERGED_JSON_DATA}; or {exportModule} = {MERGED_JSON_DATA} when string passed |
concatArrays |
Boolean |
false |
Whether to concatenate arrays instead of merging |
mergeArrays |
Boolean |
true |
Whether to merge arrays or overwrite completely |
customizer |
Function |
Custom merge function for use with mergeWith |
|
jsonReplacer |
Function |
Custom JSON replacer function passed to stringify | |
jsonSpace |
String |
\t |
String used for white space by stringify |
json5 |
Boolean |
false |
Use JSON5 instead of JSON for parse and stringify |
Examples
var merge = require('gulp-merge-json');
/**
* Basic functionality
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge())
.pipe(gulp.dest('./dist'));
/**
* Edit JSON with function
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
fileName: 'file.json',
edit: (parsedJson, file) => {
if (parsedJson.someValue) {
delete parsedJson.otherValue;
}
return parsedJson;
},
}))
.pipe(gulp.dest('./dist'));
/**
* Edit final JSON with transformer function
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
fileName: 'file.json',
transform: (mergedJson) => {
return {
key: {
type: 'data',
...mergedJson,
};
};
},
}))
.pipe(gulp.dest('./dist'));
/**
* Provide a default object (files are merged in order so object values will be overwritten)
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
startObj: { someKey: 'defaultValue' },
}))
.pipe(gulp.dest('./dist'));
/**
* Provide an overwriting object (merged at the end)
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
endObj: { someKey: 'specialValue' },
}))
.pipe(gulp.dest('./dist'));
/**
* Output module.exports = {JSON_DATA}
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
exportModule: true,
}))
.pipe(gulp.dest('./dist'));
/**
* Output a custom variable = {JSON_DATA}
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
fileName: 'dataModule.js',
exportModule: 'const myVar',
}))
.pipe(gulp.dest('./dist'));
/**
* Provide replacer and space options for JSON.stringify
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
jsonSpace: ' ',
jsonReplacer: (key, value) => {/*...*/}
})
.pipe(gulp.dest('./dist'));
/**
* Use a customizer function for custom merging behavior
*/
gulp.src('jsonFiles/**/*.json')
.pipe(merge({
customizer: (objA, objB) => {
// Example: Concat arrays but only keep unique values
if (Array.isArray(objA) && Array.isArray(objB)) {
return objA.concat(objB).filter((item, index, array) => (
array.indexOf(item) === index
));
}
return undefined;
},
}))
.pipe(gulp.dest('./dist'));
/**
* JSON5
*/
gulp.src('jsonFiles/**/*.json5')
.pipe(merge({
json5: true,
}))
.pipe(gulp.dest('./dist'));Example Input
/*
json/defaults.json
*/
{
"key1": {
"data1": "value1",
"data2": "value2"
},
"key2": {
"dataA": "valueA",
"dataB": {
"a": "b",
"c": "d"
}
}
}
/*
json/development.json
*/
{
"key1": {
"data1": "devValue"
},
"key2": {
"dataB": {
"c": "DEV MODE!"
}
},
"key3": {
"important": "value"
}
}Example Output
/*
dist/combined.json
*/
{
"key1": {
"data1": "devValue",
"data2": "value2"
},
"key2": {
"dataA": "valueA",
"dataB": {
"dataA": "valueA",
"dataB": {
"a": "b",
"c": "DEV MODE!"
}
}
},
"key3": {
"important": "value"
}
}