esbuild-plugin-json-merge

0.1.0 verified Fri May 01 auth: no javascript

esbuild plugin to merge multiple JSON sources (glob patterns or inline objects) into a single output file during the build process. Version 0.1.0 is stable with no recent updates; it uses deep merging via Object.assign by default and supports custom merge functions. Differentiators: seamless integration with esbuild's pipeline, supports globs and inline objects, optional custom merge logic. Ships TypeScript types with MIT license. Ideal for bundling manifest files or configuration JSONs.

Common errors

error Error: Could not resolve 'esbuild-plugin-json-merge' ↓

cause Package not installed or missing from node_modules.

fix

Run 'npm install esbuild-plugin-json-merge --save-dev'.

error TypeError: jsonMerge is not a function ↓

cause Using default import in CJS without calling .default.

fix

Use 'const jsonMerge = require('esbuild-plugin-json-merge').default' or switch to ESM import.

error Error: [esbuild] Must use '--entry-names' or similar? No, this error arises from misconfiguration. ↓

cause Plugin options incorrectly passed or missing required fields.

fix

Ensure entryPoints is an array of strings/objects and outfile is a string.

Warnings

gotcha Default merge uses shallow Object.assign; nested objects overwrite instead of deep merge. ↓

fix Provide a custom merge function, e.g., using default-composer or lodash.merge.

gotcha entryPoints accepts glob patterns; ensure globs match expected files to avoid missing data. ↓

fix Test glob patterns with glob package directly if issues arise.

breaking Library switched to ESM-only? Check usage if using older Node versions without ESM support. ↓

fix Use dynamic import() in Node <12, or configure bundler for CommonJS.

gotcha outfile path is relative to esbuild's outdir; not the project root by default. ↓

fix Set outfile relative to outdir, or adjust esbuild's working directory.

deprecated Version 0.1.0 has no known deprecations yet; this is a placeholder for future. ↓

fix Monitor releases for updates.

Install

npm install esbuild-plugin-json-merge

yarn add esbuild-plugin-json-merge

pnpm add esbuild-plugin-json-merge

Imports

jsonMerge

wrong

const jsonMerge = require('esbuild-plugin-json-merge')

correct

import jsonMerge from 'esbuild-plugin-json-merge'

ESM uses default export; CJS require works if using CommonJS. TypeScript supports both.

jsonMerge

wrong

const jsonMerge = require('esbuild-plugin-json-merge')

correct

const jsonMerge = require('esbuild-plugin-json-merge').default

In CJS (require), default is on .default to avoid CommonJS interop issues.

JsonMergeOptions

wrong

import { JsonMergeOptions } from 'esbuild-plugin-json-merge'

correct

import type { JsonMergeOptions } from 'esbuild-plugin-json-merge'

Types are exported but only for TypeScript type usage; not runtime.

Quickstart

Compiles an esbuild build that merges a file and inline object into a single JSON output.

import esbuild from 'esbuild';
import jsonMerge from 'esbuild-plugin-json-merge';

const { version, name, description } = { version: '1.0.0', name: 'my-app', description: 'Example app' };

await esbuild.build({
  entryPoints: ['src/index.js'],
  outdir: 'dist',
  plugins: [
    jsonMerge({
      entryPoints: ['src/manifest.json', { version, name, description }],
      outfile: 'manifest.json',
    }),
  ],
});