emuto: A JavaScript repository from kantord

Website • Tutorial • Live demo • CLI version • Compile-to-JS version

Emuto is a small language for manipulating and restructuring JSON and other data files. Emuto is inspired by jq and GraphQL

Features

Transform and query data structures
Integrate with unix commands in the command line
Conversions between different file formats
Supported input formats: JSON, text, csv, tsv, dsv
Supported output formats: JSON, text
Available as a Webpack loader

Getting started

Emuto as a CLI tool

npm install -g emuto emuto-cli

Webpack loader for emuto

yarn add --dev emuto emuto-loader

What is emuto good for? Examples

Number of items in JSON file

curl my_file.json | emuto 'length'

Your karma on HackerNews

curl https://hacker-news.firebaseio.com/v0/user/kantord.json -s | emuto '$.karma'

Convert another command's output to JSON

ls | emuto -i=raw '$[0:-1]'

See number of NPM dependencies

cat package.json | emuto -c '$.dependencies | keys | length'

List available scripts in package.json

cat package.json | emuto -c '$.scripts | keys | join " · "'

Get only the relevant data from a huge JSON file

curl https://api.github.com/repos/stedolan/jq/commits |\
emuto -c 'map ($ => $ { commit { message } committer { login } } )'

Automate the restructuring of data by creating scripts with emuto

restructure.emu

#! emuto -s

$
  | map ($ => $ { commit { message } committer { login } } )
  | map ($ => {
      "committer": $.committer.login,
      "message":   $.commit.message,
    })

Calling your script

curl https://api.github.com/repos/stedolan/jq/commits | ./restructure.emu

Contributing Guide

Read our contributing guide to learn about our development process, how to create bugfixes and improvements, and how to build and test your changes to emuto.

kantord/emuto