Record Factory

client.record gives you access to all methods related to data-sync.

Prerequisite

You need to connect to the deepstream server:

const { DeepstreamClient } = require('@deepstream/client')
const client = deepstream( 'localhost:6020')
client.login()

Methods

client.record.getRecord(name)

Argument	Type	Optional	Description
name	String	false	The name of the record.

Retrieves and if necessary creates a Record with the given name. Records are persistent data structures that are synced between clients. To learn more about what they are used for and how they work, head over to the record tutorial.

const record = client.record.getRecord('user/johndoe')

info

The record will be loaded asynchronously. To ensure the record is loaded put your logic into the whenReady callback. However you can perform set operations without waiting for the record to be ready.

client.record.getList(name)

Argument	Type	Optional	Description
name	String	false	The name of the list.

Retrieves or creates a List with the given name. Lists are arrays of recordNames that clients can manipulate and observe. You can learn more about them in the list tutorial.

const beatlesAlbums = client.record.getList('albums')
beatlesAlbums.whenReady(() => {
  console.log(beatlesAlbums.getEntries())
})
/*
  [
    "album/i9l0z34v-109vblpqddy",
    "album/i9l0z3v4-ibrbp139rbr",
    "album/i9l0z4d8-1w0p8xnk1sy"
  ]
*/

info

The list will be loaded asynchronously. To ensure the list is loaded put your logic into the whenReady callback.

client.record.getAnonymousRecord()

Returns an AnonymousRecord.

An AnonymousRecord is a record that can change its name. It acts as a wrapper around an actual record that can be swapped out for another one whilst keeping all bindings intact. You can learn more about anonymous records here.

const record = client.record.getAnonymousRecord()
record.setName('user/johndoe')
record.setName('user/maxpower')

client.record.names()

Returns all the available data-sync names.

Please note: Lists, AnonymousRecords and Records are all essentially the same thing within the SDK, so this array will contain a list of everything.

Due to how records work as well even after a discard this list will take a while to update. This is intentional as their is an option for how long a record will survive before being discarded! You can change that via the recordDiscardTimeout: milliseconds option.

client.record.has(name, callback | Promise)

Argument	Type	Optional	Description
name	String	false	The name of the record.
callback	Function	true	Arguments are (String) error and (Boolean) hasRecord

The callback contains an error argument and a boolean to indicate whether or not the record exists in deepstream. This is useful to avoid creating a record via getRecord( name ) if you only want to edit the contents. The callback is invoked immediately if the record exists on the client.

// Callback
client.record.has('user/johndoe', (error, hasRecord) => {
  // ...
})

// Promise
try {
  const hasRecord = await client.record.has('user/johndoe')
  // ...
} catch (error) {

}

client.record.head(name, callback | Promise)

Argument	Type	Optional	Description
name	String	false	The name of the record.
callback	Function	true	Arguments are (String) error and (Number) version

The callback contains an error argument and a number to indicate the current record version in deepstream.

// Callback
client.record.head('user/johndoe', (error, version) => {
  // ...
})

// Promise
try {
  const recordVersion = await client.record.head('user/johndoe')
  // ...
} catch (error) {

}

client.record.snapshot(name, callback | Promise)

Argument	Type	Optional	Description
name	String	false	The name of the record.
callback	Function	true	Arguments are (String) error and (Object) data

The callback contains the record's content without subscribing to updates. This can be used to avoid scenarios where you would request the record and discard it immediately afterwards. The callback is invoked immediately if the record data is already loaded and ready.

// Callback
client.record.snapshot('user/johndoe', (error, data) => {
    // ...
})

// Promise
try {
  const data = await client.record.snapshot('user/johndoe')
} catch (error) {

}

client.record.setData(name, path, data, callback)

Argument	Type	Optional	Description
name	String	false	The name of the record.
path	String	true	The path of the record to set data.
data	Various	false	The data to set on the record.
callback	Function	true	Arguments are (String) error

An upsert operation that allows updating of a record without being subscribed to it. If the record does not exist deepstream will try and permission the request to create the record. The callback if provided will be called with any errors that occurred while writing to the record.

// Set the entire record's data - record will be created if it doesn't exist
client.record.setData('user/homer', { status: 'married' })

// Update only marriage status
record.set('user/homer', 'status', 'single')

// Set the entire record's data with write acknowledgement
client.record.setData('user/homer', { status: 'married' }, (error) => {
  // ...
})

// Update only a property with write acknowledgement
client.record.setData('user/homer', 'son', 'Bart', (err) => {
  // ...
})

client.record.setDataWithAck(name, path, data)

The same as setData but returns a Promise.

client.record.listen(pattern, callback)

Argument	Type	Optional	Description
pattern	String (regex)	false	The pattern to match records which subscription status you want to be informed of
callback	Function	false	A function that will be called whenever a record matching the pattern has been initially subscribed to. When there are no more subscriptions to any records matching pattern, the callback passed to response.onStop() is called. Arguments are (String) match, and response (Object).

Allows to listen for record subscriptions made by other clients. This is useful to create "active" data providers, e.g. providers that only provide data for records that users are actually interested in. You can find more about listening in the record tutorial.

The callback is invoked with three arguments:

• match: The name of the record that has been matched against the provided pattern
• response: contains two functions (accept and reject), one of them needs to be called

client.record.listen('raceHorse/.*', (match, response) => {
  // see tutorial for more details
})

info

The callback will be called for all matching subscriptions that already exist at the time its registered.

client.record.unlisten(pattern)

Argument	Type	Optional	Description
pattern	String (regex)	false	The previously registered pattern

client.record.unlisten('raceHorse/.*')

Removes a listener that was previously registered using listen().

client.record.notify(recordNames, callback? | Promise)

Argument	Type	Optional	Description
recordNames	Array	false	The record names to be notified of data changes
callback	Function	true	Arguments are (String) error

Notify that the record data was changed at the database without using deepstream APIs. Useful for third party integrations.

client.record.notify(['raceHorse', 'pony'], (error) => {
  // ...
})

// Promise
try {
  const data = await client.record.notify(['raceHorse', 'pony'])
} catch (error) {
  // ...
}

client.record.setMergeStrategy (recordName, mergeStrategy)

Argument	Type	Optional	Description
recordName	String	false	The record name merge strategy to be changed
mergeStrategy	Function	false	Merge strategy to be set for the record

Set merge strategy for a given record. See handling data conflicts for more information.

client.record.setMergeStrategyRegExp (pattern, mergeStrategy)

Argument	Type	Optional	Description
pattern	String(regex)	false	The reg exp to match record names for which the merge strategy is to be changed
mergeStrategy	Function	false	Merge strategy to be set for the records

Set merge strategy for a given record. See handling data conflicts for more information.

client.record.saveToOfflineStorage()

Save all records in memory to offline storage

client.record.saveToOfflineStorage()

client.record.clearOfflineStorage(callback? | Promise)

Clears offline storage data