Plasma v4

Implementation of node-organic/Plasma v1.0.0.

Public API

plasma.emit(c [, callback]) : Promise

Immediatelly triggers any reactions matching given c chemical.

arguments

• c - Emitted chemical
  • as String equals to { type: String, ... } Chemical
  • as Object equals to Chemical

returns

• Promise<Array> - returns a Promise which resolves to Array of Objects been the result of any reactions triggered by the emit.

throws

• Array<Error> - throws an Array of Error objects

notes

• Awaits any reactions in sequence based on their registration via plasma.on
• Halts when a reaction throws
• Doesn't halt when a reaction returns error via callback signature

plasma.emitOnce(c) : Promise

Does the same as plasma.emit but triggers only the first matched reaction.

returns

• Promise - returns a Promise which resolves to the result of the reaction matched by the emit pattern.

plasma.store(c) : Promise

Does the same as plasma.emit but also triggers any reactions registered in the future using plasma.on

This method actually stored inmemory the c chemical referenced within the plasma as storedChemical.

returns

• Promise<Array> - returns a Promise which resolves to Array of Objects been the result of any reactions been triggered by the emit.

plasma.storeAndOverride(c) : Promise

Does the same as plasma.emit but also triggers any reactions registered in the future using plasma.on.

It overrides previously stored chemicals having the same chemical using c.type

returns

• Promise<Array> - returns a Promise which resolves to Array of Objects been the result of any reactions been triggered by the emit.

plasma.has(pattern) : boolean

Checks synchronously for stored chemicals by given pattern.

returns

• Boolean - returns true when plasma contains a stored chemical matching given pattern

plasma.get(pattern) : Chemical

Returns synchronously first found stored chemical by given pattern.

plasma.getAll(pattern) : Array [ Chemical ]

Returns synchronously all stored chemicals by given pattern.

plasma.on(pattern, function (c [, callback]){} [, context])

Registers a function to be triggered when chemical emitted in plasma matches given pattern.

arguments

• pattern - matches emitted chemicals
  • as String matching Chemical.type property
  • as Object matching one or many properties of Chemical
• c - Object Chemical matching pattern
• callback - optional callback function used for feedback
• context - optional context to be used for calling the function

example

plasma.on({type: 'myChemical', kind: 'v1'}, async function (c) {
  console.log(c) // {type: 'myChemical', kind: 'v1', ...}
  await operation()
  return result
})

let result = await plasma.emit({
  type: 'myChemical',
  kind: 'v1',
  property: 'value'
})

plasma.once(pattern, function (c [, callback]){} [, context])

The same as plasma.on(pattern, function reaction (c){}) but will trigger the function only once.

plasma.on([p1, p2, ...], function (c1, c2, ...){} [, context])

Registers a function to be triggered when all chemicals emitted in plasma have been matched.

arguments

• p - array
  • having elements String matching Chemical.type property
  • having elements Object matching one or many properties of Chemical
• c - array
  • Object Chemicals matching p array maintaining their index order
• context - optional context to be used for calling the function

plasma.once([p1, p2, ...], function (c1, c2, ...) {} [, context])

The same as plasma.on([p1, p2], function(c1, c2){}) but will trigger the function only once.

plasma.off(pattern, function, context)

Unregisters chemical reaction functions, the opposite of plasma.on or plasma.once.

arguments

• pattern
  • as String or Array or Object - needs function handler for unregister to succeed
  • as Function - finds all registered chemical reactions with that function handler and unregisters them.
• function optional required only when pattern is String, Array or Object. This should be the exact function used for plasma.on or plasma.once
• context optional used to scope removing of chemical reactions within context

plasma.off(function, context)

Unregisters chemical reaction functions, the opposite of plasma.on or plasma.once.

arguments

• function this should be the exact function used for plasma.on or plasma.once
• context optional used to scope removing of chemical reactions within context

plasma.trash(c)

Removes previously stored chemical via plasma.store. It does removal by reference and won't throw exception if given chemical is not found in plasma's store.

plasma.trashAll(pattern)

Removes previously stored chemicals via plasma.store. It does removal by chemical pattern

plasma.pipe(function(c){})

Method which will invoke function per any chemical been emitted or stored in plasma.

plasma.unpipe(function(c){})

Stops invoking given function previously used for plasma.pipe

Features

Current implementation of organic plasma interface has the following addon features designed for ease in daily development process.

optional usage of arguments

Invoking either:

• plasma.emit('ready')
• plasma.emit({type: 'ready'})

triggers all the following:

• plasma.on('ready', function(c){ c.type === 'ready' })
• plasma.on({type: 'ready'}, function(c){ c.type === 'ready' })

feedback support

using callback

plasma.on('c1', function reaction1 (c, callback) {
  callback(c)
})
plasma.emit('c1', function callback (c) {
  // c.type === 'c1'
})

using async/await

plasma.on('c1', async function reaction1 (c) {
  let result
  return result
})
let result = await plasma.emit('c1')
console.log(result)

custom pattern <-> chemical match algorithms

• override plasma.utils.deepEqual(pattern, chemical)

match chemicals using class definitions as pattern

var Class1 = function () {}
plasma.on(Class1, function (instance) {

})
var instance = new Class1()
plasma.emit(instance)

throw on missing listeners/handlers for a chemical

When emitting a chemical (via the .emit method) which has no registered handlers (via the .on/.once methods) an Error will be thrown

• The missing handlers error chemical will not be thrown when storing chemicals.
• by default this feature is disabled unless throwOnMissingHandler value is set to true

var instance  = new Plasma({
  throwOnMissingHandler: true
})

instance.emit("chemicalWithNoHandler") // throws Error