PCIdempotency

maintained by PandaClouds.com

PCIdempotency provides a clean way to ensure that multiple save attempts only result in a single object.

Installation

1. If you want to use this library, you first need to install the Node.js.

2. When you install node.js, will also be installed npm.

3. Please run the following command.

npm install --save @panda-clouds/idempotency

Usage

Node.js

const PCIdempotency = require('@panda-clouds/idempotency');

// example "beforeSave" usage

// example generic ussage with Parse
await PCIdempotency.check('Foo', Parse); // pass
await PCIdempotency.check('Bar', Parse); // pass
await PCIdempotency.check('Bar', Parse); // throws because 456 has already been given

// example generic ussage without Parse
// Note: without parse we only remember the last 500 keys
await PCIdempotency.check('123'); // pass
await PCIdempotency.check('456'); // pass
await PCIdempotency.check('456'); // throws because 456 has already been given

You can replace PCIdempotency with any variable.

Methods

Unit Tests are an additional resource for learning functionality.

- checkOnCreate(key, Parse)

will throw an error if the object contains a duplicate value for the key "idempotencyKey"

Example:

// Parse Server v3.x

Parse.Cloud.beforeSave('MyObject', async request => {
	await PCIdempotency.checkOnCreate(request, Parse)
})

// Parse Server v2.x

Parse.Cloud.beforeSave('MyObject', (request, response) => {
	return Parse.Promise.as()
	.then(()=>{
	  return PCIdempotency.checkOnCreate(request, Parse)
	})
	.then(()=>{
		response.success('yay');
	},(error)=>{
		response.error(error);
	})
})

- check(key, Parse)

will throw an error if we have used that key before

Example:

await PCIdempotency.check('myKey')
// better yet, to add persistance, use
await PCIdempotency.check('myKey', Parse)

Contributions

Pull requests are welcome! here is a checklist to speed things up:

• modify PCIdempotency.js
• add unit tests in PCIdempotency.spec.js
• run npm test
• document method in README.md
• add your name to 'Contributors' in README.md

Contributors

(Add your name)

• [*] Marc Smith