aedes-persistence




The spec for an Aedes persistence, with abstract
tests and a fast in-memory implementation.

* Install
* API
* Implement another persistence
* License

Install

To install aedes-persistence, simply use npm:

``
npm install aedes-persistence --save
`




API

* persistence()
* instance.storeRetained()
* instance.createRetainedStream()
* instance.createRetainedStreamCombi()
* instance.addSubscriptions()
* instance.removeSubscriptions()
* instance.subscriptionsByClient()
* instance.countOffline()
* instance.subscriptionsByTopic()
* instance.cleanSubscriptions()
* instance.outgoingEnqueue()
* instance.outgoingEnqueueCombi()
* instance.outgoingUpdate()
* instance.outgoingClearMessageId()
* instance.outgoingStream()
* instance.incomingStorePacket()
* instance.incomingGetPacket()
* instance.incomingDelPacket()
* instance.putWill()
* instance.getWill()
* instance.delWill()
* instance.streamWill()
* instance.getClientList()
* instance.destroy()

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$3

Creates a new instance of a persistence, that is already ready to
operate. The default implementation is in-memory only.

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$3

Store a retained message, calls the callback when it was saved.

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$3

Return a stream that will load all retained messages matching the given
pattern (according to the MQTT spec) asynchronously. Deprecated.

-------------------------------------------------------



$3

Return a stream that will load all retained messages matching given
patterns (according to the MQTT spec) asynchronously.

-------------------------------------------------------



$3

Add the given offline subscriptions for the given
Client. The client __must__
have connected with clean: false, as this is not checked here.
This is called when a client issue a SUBSCRIBE packet.

subscriptions is in the same format of the subscribe property in the
SUBSCRIBE packet:

`js
[{
topic: 'hello/world',
qos: 1,
}, {
topic: 'hello/#',
qos: 2,
}]
`

-------------------------------------------------------



$3

The inverse of addSubscriptions but subscriptions is an array of topic names.

-------------------------------------------------------



$3

Returns all the offline subscriptions for the given client. Called when
a client with clean: false connects to restore its subscriptions.

subscriptions is in the same format of the subscribe property in the
SUBSCRIBE packet:

`js
[{
topic: 'hello/world',
qos: 1,
}, {
topic: 'hello/#',
qos: 2,
}]
`

-------------------------------------------------------



$3

Returns the number of offline subscriptions and the number of offline
clients.

-------------------------------------------------------



$3

Returns all the offline subscriptions matching the given pattern. Called when
a PUBLISH with qos: 1 or qos: 2 is received.

The subscriptions are in the format:

`js
{
clientId: client.id,
topic: sub.topic,
qos: sub.qos
}
`

-------------------------------------------------------



$3

Removes all offline subscriptions for a given client.

-------------------------------------------------------



$3

Enqueue a potentially offline delivery. subscription is one of the
objects returned by subscriptionsByTopic. Deprecated.

-------------------------------------------------------



$3

Enqueue a potentially offline delivery. subscriptions is the whole subscriptions
objects returned by subscriptionsByTopic.

-------------------------------------------------------



$3

Called before a (potentially) offline packet is delivered, the caller
should update the packet.messageId before updating.

-------------------------------------------------------



$3

Removes a packet with the given messageId (passing a PUBACK is ok)
from the persistence. Passes back original packet to the callback.

-------------------------------------------------------



$3

Return a stream that will load all offline messages for the given client asynchronously.

-------------------------------------------------------



$3

Store an incoming packet for the given client. Used for QoS 2.

-------------------------------------------------------



$3

Retrieve an incoming packet with the same messageId for the given client. Used for QoS 2.

-------------------------------------------------------



$3

Deletes incoming packet with the same messageId for the given client. Used for QoS 2.

-------------------------------------------------------



$3

Stores the will of a client. Used to support multi-broker environments
and to not lose wills in case of a crash.

-------------------------------------------------------



$3

Retrieves the will of a client. Used to support multi-broker environments
and to not lose wills in case of a crash.

-------------------------------------------------------



$3

Removes the will of a client. Used to support multi-broker environments
and to not lose wills in case of a crash.

-------------------------------------------------------



$3

Streams all the wills for the given brokers. The brokers are in the
format:

`js
{
mybroker: {
brokerId: 'mybroker'
}
}
`

-------------------------------------------------------



$3

Returns a stream which has all the clientIds subscribed to the
specified topic




$3

Destroy current persistence. Use callback cb(err) to catch errors if any




Implement another persistence

A persistence needs to pass all tests defined in
./abstract.js. You can import and use that test suite
in the following manner:

`js
const test = require('tape').test
const myperst = require('./')
const abs = require('aedes-persistence/abstract')

abs({
test: test,
persistence: myperst
})
`

If you require some async stuff before returning, a callback is also
supported:

`js
const test = require('tape').test
const myperst = require('./')
const abs = require('aedes-persistence/abstract')
const clean = require('./clean') // invented module

abs({
test: test,
buildEmitter: require('mymqemitter'), // optional
persistence: function build (cb) {
clean(function (err) {
cb(err, myperst())
})
}
})
``

Collaborators

* __Gnought__

License

MIT