https://github.com/apostrophecms/prettiest

Improbably easy data storage and locking for command line scripts. Pairs well with shelljs and a nice chianti.
https://github.com/apostrophecms/prettiest

Last synced: about 2 months ago
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Improbably easy data storage and locking for command line scripts. Pairs well with shelljs and a nice chianti.

• Host: GitHub
• URL: https://github.com/apostrophecms/prettiest
• Owner: apostrophecms
• Created: 2014-12-19T18:52:31.000Z (about 10 years ago)
• Default Branch: master
• Last Pushed: 2020-01-04T23:21:12.000Z (almost 5 years ago)
• Last Synced: 2024-10-14T11:04:24.104Z (3 months ago)
• Language: JavaScript
• Homepage:
• Size: 5.86 KB
• Stars: 77
• Watchers: 15
• Forks: 4
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
# prettiest

```javascript

// The simplest script: keeps track of how many

// times it has been run. It's like magic!

var data = require('prettiest')();

data.count = data.count || 0;

data.count++;

console.log('I have been run ' + data.count + ' times.');

```

`prettiest` provides simple command line apps with two important features:

1. **Persistent data.** Any changes made to the data object returned by `prettiest` are automatically saved when the app exits.

2. **Concurrency locks.** If two copies of your app start at the same time, the second one will always wait for the first one to finish before it proceeds.

If you're replacing a shell script with something a little smarter, this module is a great companion for [shelljs](http://documentup.com/arturadib/shelljs).

## Install

`npm install prettiest`

## Options

You can specify where the JSON data file lives:

```javascript

var data = require('prettiest')({ json: __dirname + '/mydatafile.json' });

```

If you don't, the JSON file lives in the same directory with your app, and will be called `data.json`.

`prettiest` also creates a lock file, which will have the same name as the JSON file, plus `.lock` at the end. To prevent race conditions, the lock file is not removed. Just leave it be.

## Caveats

* The save-and-unlock behavior lives in a `process.on('exit')` handler. Which is great, actually, but just bear in mind it won't fire if node itself crashes. In which case your `data` object probably isn't ready to save anyway, right?

* You don't want to use this in a web application. Duh. It's a simple, synchronous bit of magic for use in utilities with short execution times.

* You don't want to use this in a super-long-running script, because it only saves your data to disk at the very end. It's meant for utilities that do a relatively simple job and then exit.

## Questions

* "Can my code still be asynchronous?" Sure, knock yourself out. The save-and-unlock logic runs when your code exits.

## Credits

`prettiest` was built for [ApostropheCMS](https://apostrophecms.com).

## Changelog

1.1.0: dependency on `fs-ext` bumped to 2.0.0, in hopes of smoother cross-platform compilation than with the prereleases. Moved to `const` and `let` since they are supported back to well before currently supported versions of node.

1.0.0: accepted pull request to use newer `fs-ext` because of compilation issues on newer systems. Thanks to Kerrick. Bumped to 1.0.0 stable. Now following semver.

0.1.0: initial release.