Registry / serialization / js-yaml-loader

js-yaml-loader

library1.2.2jsnpmunverified

A Webpack loader that transpiles YAML files into JavaScript objects using js-yaml. Version 1.2.2 (latest) is stable with no active development since 2019. Unlike yaml-loader which outputs JSON, this loader supports YAML types disallowed in JSON (e.g., Infinity, RegExp, Function) via js-yaml's load. Options include safe load (default true) and iterator for multi-document YAML. Compatible with Webpack 4+.

serialization devops

npm install js-yaml-loader

github ↗package ↗

INSTALL

IMPORT

SIG · JS-YAML-LOADER

js-yaml-loader

serializationjavascriptv1.2.2

Install

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Import

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Disk

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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 (loader)

✓ import doc from 'js-yaml-loader!./file.yml'

✗ require('js-yaml-loader!./file.yml')

Inline loader syntax with import is the expected usage.

config rule

✓ module.exports = { module: { rules: [{ test: /\.yaml$/, use: 'js-yaml-loader' }] } }

✗ module.exports = { module: { loaders: [{ test: /\.yaml$/, loader: 'js-yaml-loader' }] } }

Use 'use' and 'rules' in Webpack 4+. 'loaders' is deprecated.

options

✓ module.exports = { module: { rules: [{ test: /\.yaml$/, use: { loader: 'js-yaml-loader', options: { safe: false } } }] } }

✗ module.exports = { module: { rules: [{ test: /\.yaml$/, loader: 'js-yaml-loader?safe=false' }] } }

Pass options as object in Webpack 4+; query string syntax works but is less flexible.

Configures Webpack to import YAML files as JavaScript objects with safe loading by default.

// webpack.config.js module.exports = { module: { rules: [ { test: /\.(yaml|yml)$/, use: [ { loader: 'js-yaml-loader', options: { safe: true } // default, prevents unsafe types } ] } ] } }; // In your source file: import config from './config.yaml'; console.log(config.database.host);

Debug

Known issues

gotchasafeLoad is used by default, which disables unsafe YAML types (RegExp, Function, undefined). Set safe: false to allow them.

fix

Add option { safe: false } to loader configuration or inline query: js-yaml-loader?safe=false

affects: >=1.0.0

gotchaThis loader outputs JavaScript objects, not JSON. If you expect a JSON string, use yaml-loader instead.

fix

Use yaml-loader if JSON output is needed.

affects: >=1.0.0

gotchaThe package is in maintenance mode; no updates since 2019. Consider alternatives for Webpack 5+ compatibility.

fix

Test with Webpack 5 or migrate to yaml-loader or custom loader.

affects: >=1.0.0

Errors

Common errors & fixes

Module parse failed: Unexpected token (1:1) You may need an appropriate loader to handle this file type.

Webpack cannot parse YAML files because the loader rule is missing or misconfigured.

fix

Add a rule for .yaml files using js-yaml-loader: { test: /\.yaml$/, use: 'js-yaml-loader' }

Error: Cannot find module 'js-yaml'

js-yaml is a peer dependency and must be installed separately.

fix

Run: npm install js-yaml

TypeError: (0 , _jsYaml.safeLoad) is not a function

The js-yaml package version is too old or incompatible; safeLoad was renamed in js-yaml v4.

fix

Ensure js-yaml version 3.x is installed (npm install js-yaml@3)

Upgrade

Version history

1.2.2latest on npm

Audit

Dependencies

js-yamloptionalPeerdependency for YAML parsing

Agent activity

12 hits · last 30 days

node

Resources

githubhttps://github.com/wwilsman/js-yaml-loader ↗

packagehttps://www.npmjs.com/package/js-yaml-loader ↗