Registry / serialization / messageformat-loader

messageformat-loader

library0.8.1jsnpmunverified

Webpack loader that compiles MessageFormat ICU message strings into JavaScript modules at build time. Supports JSON, YAML, and JS source files containing ICU MessageFormat strings. Compatible with messageformat 1.x and 2.x. The loader transforms message resources into pre-compiled functions for efficient runtime internationalization. While the core messageformat library has moved to v4 (prerelease) with a rewritten API and MF2 spec support, this loader remains at v0.8.1 and only supports the older 1.x/2.x versions. Key differentiator: integrates MessageFormat compilation into webpack pipeline, avoiding runtime compilation overhead.

serialization web-framework

npm install messageformat-loader

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · MESSAGEFORMAT-LOAD

messageformat-loader

serializationjavascriptv0.8.1

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

default export

✓ // In webpack.config.js: module.exports = { module: { rules: [ { test: /\.json$/, use: 'messageformat-loader' } ] } }

✗ loader: 'messageformat-loader' // string is fine; but if using options object, must specify properly

Loader is used in webpack config, not in application code. Configure with 'messageformat-loader' as the loader name.

Configures webpack to load JSON message files and compile ICU patterns using messageformat-loader.

// webpack.config.js module.exports = { entry: './src/index.js', module: { rules: [ { test: /\.json$/, // or .yaml, .yml use: [ { loader: 'messageformat-loader', options: { locale: 'en', // default locale locales: ['en', 'fr'], // available locales biDiSupport: false } } ] } ] } }; // src/messages/en.json { "greeting": "Hello {name}!", "items": "You have {count, plural, =0 {no items} one {# item} other {# items}}." } // src/index.js import messages from './messages/en.json'; console.log(messages.greeting({ name: 'World' })); // "Hello World!" console.log(messages.items({ count: 3 })); // "You have 3 items."

Debug

Known issues

gotchaLoader only supports messageformat 1.x or 2.x; does not work with messageformat v4

fix

Use messageformat 2.x (e.g., 'messageformat': '^2.0.0') or stay on 1.x. Do not install messageformat@4.

affects: >=0.8.0

deprecatedThe loader is no longer actively maintained; the underlying messageformat library has moved to v4 with a completely different API

fix

Consider migrating to messageformat v4 and using a custom loader or runtime compilation with @messageformat/core

affects: >=0.8.0

gotchaLocale option is required; if not provided, the loader falls back to 'en' but may produce incorrect date/number formatting for other locales

fix

Always specify the 'locale' or 'locales' option matching your message files

affects: >=0.8.0

Errors

Common errors & fixes

Module not found: Error: Can't resolve 'messageformat' in '...'

Missing peer dependency messageformat

fix

npm install messageformat@^2.0.0

Error: Cannot find module 'messageformat/compile-module'

messageformat version not compatible (e.g., v4 installed)

fix

npm install messageformat@^2.0.0

TypeError: messageformat_loader is not a function

Using loader incorrectly in webpack config (e.g., as a plugin)

fix

Configure as `loader: 'messageformat-loader'` inside a `rules` array, not as a plugin.

Upgrade

Version history

0.8.1latest on npm

Audit

Dependencies

messageformatrequiredRequired peer dependency; must be installed separately as messageformat 1.x or 2.x

Agent activity

3 hits · last 30 days

node

Amazon

Resources

githubhttps://github.com/messageformat/messageformat ↗

packagehttps://www.npmjs.com/package/messageformat-loader ↗

homepagehttps://messageformat.github.io/ ↗