Receive object messages from a Pear application's processes/threads using object pattern-matching
npm install pear-messages> Receive object messages from a Pear application's processes/threads using object pattern-matching
``js
import messages from 'pear-messages'
const stream = messages({ some: 'props' })
stream.once('data', console.log)
`
Elsewhere in app use pear-message:
`js
import message from 'pear-message'
await message({ some: 'props', to: { pattern: ['match', 'against'] } })
`
Should log: { some: 'props', to: {pattern: ['match', 'against'] }}
Listen for application messages sent with pear-message based on pattern which is an object whose properties match a subset of the properties for a given target message.
A function which accepts a pattern object and returns an Iambus subscriber (which inherits from streamx Readable) which emits message objects matching a provided pattern object.
If no pattern object or an empty pattern object is provided all messages will be emitted. A pattern object is an object (typically) containing a subset of matching values for a given target object. Message objects can be user generated or platform generated.
The subscriber stream has a data event which can be listened to, it can also be consumed with for await and an listener function can be passed in addition to pattern (message(pattern, listener)) or as a single argument (messages(listener)) (indicating a catch-all pattern).
A message object may have any properties. Platform-generated messages are given a type property.
The message stream is auto-ended during Pear.teardown.
#### Examples:
Listen for an internal platform message using a pattern object and listener function:
`js
import messages from 'pear-messages'
messages({ type: 'pear/wakeup' }, ({ data, link }) => {
console.log('pear/wakeup', data, link)
})
`
Tiny utility module which logs all messages using for await:
`js
import messages from 'pear-messages'
for await (const message of messages()) {
if (global.LOGBUS) console.log('BUS:', message)
}
`
Use message to create an application message:
`js
import message from 'pear-message'
import messages from 'pear-messages'
const ctaClicks = messages({ type: 'my-app/user-cta' })
ctaClicks.on('data', (msg) => {
console.log('cta click', msg)
})
// elsewhere
onUserClickCta((event, data) => {
message({ type: 'my-app/user-cta', event, data })
})
``
Apache-2.0