Constructor

Constructor

The Ably REST library constructor is overloaded allowing it to be instantiated using a ClientOptions object, or more simply using a string containing an API key or Token.

new Ably.Rest(String keyOrTokenId)

This will instantiate the REST library with the provided API key or Token ID string.

new Ably.Rest(ClientOptions clientOptions)

This will instantiate the library using the specified ClientOptions.

The REST constructor is used to instantiate the library. The REST library may be instantiated multiple times with the same or different ClientOptions in any given context. Except where specified otherwise, instances operate independently of one another.

Authentication

The REST library needs to have credentials to be able to authenticate with the Ably service. Ably supports both Basic and Token based authentication schemes. Read more on authentication.

Basic Authentication

A private API key string for ClientOptions#key or the constructor, as obtained from the application dashboard, is required for Basic Authentication. Use this option if you wish to use Basic authentication, or if you want to be able to request Ably Tokens without needing to defer to a separate entity to sign Ably TokenRequests. Note that initializing the library with a key does not necessarily mean that the library will use Basic auth; using the private key it is also able to create and sign Ably TokenRequests and use token authentication when necessary.

Token Authentication

The ClientOptions#token option takes a token string, and assumes that the Ably-compatible token has been obtained from some other instance that requested the token. Use the token option if you are provided with a token to use and you do not have a key (or do not have a key with the capabilities that you require).

Since tokens are short-lived, it is rarely sufficient to start with a token without the means for refreshing it. The authUrl and authCallback options are provided to allow a user of the library to provide new Ably-compatible tokens or Ably TokenRequests to the library as required; using these options allows the library to be instantiated without a key or token, and an initial token will be obtained automatically when required.

Read more on authentication.

Ably.Rest Properties

The REST client exposes the following public properties:

auth

A reference to the Auth authentication object configured for this client library.

push

A reference to the Push object in this client library.

channels

Channels is a reference to the Channel collection instance for this library indexed by the channel name. You can use the Get method of this to get a Channel instance. See channels and messages for more information.

Ably.Rest Methods

stats

stats(Object params?): Promise<PaginatedResult<Stats>>

This call queries the REST /stats API and retrieves your application's usage statistics. A PaginatedResult is returned, containing an array of Stats for the first page of results. PaginatedResult objects are iterable providing a means to page through historical statistics. See an example set of raw stats returned via the REST API.

See statistics for more information.

Parameters

ParameterDescription
paramsAn optional set of parameters used to specify which statistics are retrieved. If not specified the default parameters will be used

params properties

The following options, as defined in the REST /stats API endpoint, are permitted:

ParameterDescriptionTypeDefault
startEarliest time in milliseconds since the epoch for any stats retrievedNumberbeginning of time
endLatest time in milliseconds since the epoch for any stats retrievedNumbercurrent time
directionforwards or backwardsStringbackwards
limitMaximum number of stats to retrieve up to 1,000Number100
unit Based on the unit selected, the given start or end times are rounded down to the start of the relevant interval depending on the unit granularity of the queryStatsIntervalGranularityminute

Returns

Returns a promise. On success, the promise is fulfilled with a PaginatedResult object containing an array of Stats objects. On failure, the promise is rejected with an ErrorInfo object.

time

time(): Promise<Number>

Obtains the time from the Ably service as milliseconds since epoch. (Clients that do not have access to a sufficiently well maintained time source and wish to issue Ably TokenRequests with a more accurate timestamp should use the queryTime clientOptions instead of this method).

Returns

Returns a promise. On success, the promise is fulfilled with the time as milliseconds since the Unix epoch. On failure, the promise is rejected with an ErrorInfo object.

request

request(method, path, version, params?, body?, headers?): Promise<HttpPaginatedResponse>

Makes a REST request to a provided path. This is provided as a convenience for developers who wish to use REST API functionality that is either not documented or is not yet included in the public API, without having to handle authentication, paging, fallback hosts, MsgPack and JSON support, etc. themselves.

Parameters

ParameterDescriptionType
methodeither get, post, put, patch or deleteString
paththe path to queryString
versionversion of the REST API to useNumber
params(optional) any querystring parameters neededObject
body(optional; for post, put and patch methods) the body of the request, as anything that can be serialized into JSON, such as an Object or ArraySerializable
headers(optional) any headers needed. If provided, these will be mixed in with the default library headersObject

Returns

Returns a promise. On success, the promise is fulfilled with the HttpPaginatedResponse object returned by the HTTP request. The response object will contain an empty or JSON-encodable object. On failure, the promise is rejected with an ErrorInfo object.

Example

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const response = await rest.request(
  'get',
  '/channels/someChannel/messages',
  3,
  { limit: 1, direction: 'forwards' },
);
console.log('Success! status code was ' + response.statusCode);
console.log(response.items.length + ' items returned');
if (response.hasNext()) {
  const nextPage = await response.next();
  console.log(nextPage.items.length + ' more items returned');
}

batchPublish

There are two overloaded versions of this method:

batchPublish(BatchPublishSpec spec): Promise<BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>>

Publishes a BatchPublishSpec object to one or more channels, up to a maximum of 100 channels.

batchPublish(BatchPublishSpec[] specs): Promise<BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>[]>

Publishes one or more BatchPublishSpec objects to one or more channels, up to a maximum of 100 channels.

Parameters

ParameterDescriptionType
specAn object describing the messages to be batch published and to which channelsBatchPublishSpec
specsAn array of objects describing the messages to be batch published and to which channelsBatchPublishSpec[]

Returns

Returns a promise. On success, the promise is fulfilled with a BatchResult object, or an array of BatchResult objects, containing information about the result of the batch publish operation for each channel. The successful results of specific channels are returned as BatchPublishSuccessResult objects, whilst failures are BatchPublishFailureResult objects. If an array of BatchResult objects are returned, they are in the same order as the provided BatchPublishSpec. On failure, the promise is rejected with an ErrorInfo object.

batchPresence

batchPresence(String[] channels): Promise<BatchResult<BatchPresenceSuccessResult | BatchPresenceFailureResult>[]>

Retrieves the presence state for one or more channels, up to a maximum of 100 channels. Presence state includes the clientId of members and their current PresenceAction.

Parameters

ParameterDescriptionType
channelsAn array of one or more channel names, up to a maximum of 100 channelsString[]

Returns

Returns a promise. On success, the promise is fulfilled with a BatchResult object containing information about the result of the batch presence request for each channel. The successful results of specific channels are returned as BatchPresenceSuccessResult objects, whilst failures are BatchPresenceFailureResult objects. On failure, the promise is rejected with an ErrorInfo object.

ClientOptions

ClientOptions is a plain JavaScript object and is used in the Ably.Rest constructor's options argument. The following attributes can be defined on the object:

Properties

ParameterDescriptionType
keyThe full key string, as obtained from the application dashboard. Use this option if you wish to use Basic authentication, or wish to be able to issue Ably Tokens without needing to defer to a separate entity to sign Ably TokenRequests. Read more about Basic authenticationString
tokenAn authenticated token. This can either be a TokenDetails object, a TokenRequest object, or token string (obtained from the token property of a TokenDetails component of an Ably TokenRequest response, or a JSON Web Token satisfying the Ably requirements for JWTs). This option is mostly useful for testing: since tokens are short-lived, in production you almost always want to use an authentication method that allows the client library to renew the token automatically when the previous one expires, such as authUrl or authCallback. Read more about Token authenticationString, TokenDetails or TokenRequest
authCallbackA functionfunction with the form function(tokenParams, callback(err, tokenOrTokenRequest)) which is called when a new token is required. The role of the callback is to obtain a fresh token, one of: an Ably Token string (in plain text format); a signed TokenRequest; a TokenDetails (in JSON format); an Ably JWT. See our authentication documentation for details of the Ably TokenRequest format and associated API calls.Callable
authUrlA URL that the library may use to obtain a fresh token, one of: an Ably Token string (in plain text format); a signed TokenRequest; a TokenDetails (in JSON format); an Ably JWT. For example, this can be used by a client to obtain signed Ably TokenRequests from an application server.String
authMethodThe HTTP verb to use for the request, either GET or POST
default: GET
String
authHeadersA set of key value pair headers to be added to any request made to the authUrl. Useful when an application requires these to be added to validate the request or implement the response. If the authHeaders object contains an authorization key, then withCredentials will be set on the xhr request.Object
authParamsA set of key value pair params to be added to any request made to the authUrl. When the authMethod is GET, query params are added to the URL, whereas when authMethod is POST, the params are sent as URL encoded form data. Useful when an application require these to be added to validate the request or implement the response.Object
tokenDetailsAn authenticated TokenDetails object (most commonly obtained from an Ably Token Request response). This option is mostly useful for testing: since tokens are short-lived, in production you almost always want to use an authentication method that allows the client library to renew the token automatically when the previous one expires, such as authUrl or authCallback. Use this option if you wish to use Token authentication. Read more about Token authenticationTokenDetails
tlsA boolean value, indicating whether or not a TLS ("SSL") secure connection should be used. An insecure connection cannot be used with Basic authentication as it would lead to a possible compromise of the private API key while in transit. Find out more about TLS
default: true
Boolean
clientIdA client ID, used for identifying this client when publishing messages or for presence purposes. The clientId can be any non-empty string. This option is primarily intended to be used in situations where the library is instantiated with a key; note that a clientId may also be implicit in a token used to instantiate the library; an error will be raised if a clientId specified here conflicts with the clientId implicit in the token. Find out more about client identitiesString
useTokenAuthWhen true, forces Token authentication to be used by the library. Please note that if a clientId is not specified in the ClientOptions or TokenParams, then the Ably Token issued will be anonymous.
default: false
Boolean
endpointEnables enterprise customers to use their own custom endpoints, which support dedicated, isolated clusters and regional message routing and storage constraints. See our platform customization guide for more details.
default: null
String
environmentDeprecated, use endpoint. Enables enterprise customers to use their own custom environments, which support dedicated, isolated clusters and regional message routing and storage constraints. See our platform customization guide for more details.
default: null
String
idempotentRestPublishingWhen true, enables idempotent publishing by assigning a unique message ID client-side, allowing the Ably servers to discard automatic publish retries following a failure such as a network fault. We recommend you enable this by default. In version 1.2 onwards, idempotent publishing for retries will be enabled by default.
default: false
Boolean
fallbackHostsAn array of fallback hosts to be used in the case of an error necessitating the use of an alternative host. When a custom environment is specified, the fallback host functionality is disabled. If your customer success manager has provided you with a set of custom fallback hosts, please specify them here.
default: [a.ably-realtime.com, b.ably-realtime.com, c.ably-realtime.com, d.ably-realtime.com, e.ably-realtime.com]
String []
transportParamsOptional. Can be used to pass in arbitrary connection parameters, such as heartbeatInterval and remainPresentForObject
logLevelA number controlling the verbosity of the log output of the library. Valid values are: 0 (no logs), 1 (errors only), 2 (errors plus connection and channel state changes), 3 (high-level debug output), and 4 (full debug output).Integer
logHandlerA function to handle each line of the library's log output. If logHandler is not specified, console.log is used.Callable
transportsAn optional array of transports to use, in descending order of preference. In the browser environment the available transports are: web_socket, xhr_polling.String[]
useBinaryProtocolIf set to true, will enable the binary protocol (MessagePack) if it is supported. It's disabled by default on browsers for performance considerations (browsers are optimized for decoding JSON). Find out more about the benefits of binary encoding
default: false
Boolean
queryTimeIf true, the library will query the Ably servers for the current time when issuing TokenRequests instead of relying on a locally-available time of day. Knowing the time accurately is needed to create valid signed Ably TokenRequests, so this option is useful for library instances on auth servers where for some reason the server clock cannot be kept synchronized through normal means, such as an NTP daemon. The server is queried for the current time once per client library instance (which stores the offset from the local clock), so if using this option you should avoid instancing a new version of the library for each request.
default: false
Boolean
defaultTokenParamsWhen a TokenParams object is provided, it will override the client library defaults when issuing new Ably Tokens or Ably TokenRequestsTokenParams

Stats object

A Stats object represents an application's statistics for the specified interval and time period. Ably aggregates statistics globally for all accounts and applications, and makes these available both through our statistics API as well as your application dashboard.

ParameterDescriptionType
appIdThe ID of the Ably application the statistics relate to.String
entriesThe statistics for the requested time interval and time period. The schema property provides further informationPartial<Record<String, Number>>
inProgressOptional. For entires that are still in progress, such as the current month, the last sub-interval included in the stats entry. In the format yyyy-mm-dd:hh:mm:ssString
intervalIdThe UTC time period that the stats coverage begins at. If unit was requested as minute this will be in the format YYYY-mm-dd:HH:MM, if hour it will be YYYY-mm-dd:HH, if day it will be YYYY-mm-dd:00 and if month it will be YYYY-mm-01:00String
schemaThe URL of a JSON schema describing the structure of the Stats objectString

StatsIntervalGranularity

StatsIntervalGranularity is an enum specifying the granularity of a Stats interval.

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const StatsIntervalGranularity = [
    'minute',
    'hour',
    'day',
    'month'
]

HttpPaginatedResponse

An HttpPaginatedResponse is a superset of PaginatedResult, which is a type that represents a page of results plus metadata indicating the relative queries available to it. HttpPaginatedResponse additionally carries information about the response to an HTTP request. It is used when making custom HTTP requests.

Properties

PropertyDescriptionType
statusCodeThe HTTP status code of the responseNumber
successWhether the HTTP status code indicates success. This is equivalent to 200 <= statusCode < 300Boolean
headersThe headers of the responseObject
errorCodeThe error code if the X-Ably-Errorcode HTTP header is sent in the responseNumber
errorMessageThe error message if the X-Ably-Errormessage HTTP header is sent in the responseString

Methods

first

first(): Promise<HttpPaginatedResponse>

Returns a promise. On success, the promise is fulfilled with a new HttpPaginatedResponse for the first page of results. On failure, the promise is rejected with an ErrorInfo object that details the reason why it was rejected.

hasNext

Boolean hasNext()

Returns true if there are more pages available by calling next and returns false if this page is the last page available.

isLast

Boolean isLast()

Returns true if this page is the last page and returns false if there are more pages available by calling next available.

next

next(callback(err, resultPage))

next(): Promise<HttpPaginatedResponse>

Returns a promise. On success, the promise is fulfilled with a new HttpPaginatedResponse loaded with the next page of results. If there are no further pages, then null is returned. On failure, the promise is rejected with an ErrorInfo object that details the reason why it was rejected.

current

current(): Promise<HttpPaginatedResponse>

Returns a promise. On success, the promise is fulfilled with a new HttpPaginatedResponse loaded with the current page of results. On failure, the promise is rejected with an ErrorInfo object that details the reason why it was rejected.

Example

The HttpPaginatedResponse interface is a superset of PaginatedResult, see the PaginatedResult example

BatchPublishSpec

A BatchPublishSpec describes the messages that should be published by a batch publish operation, and the channels to which they should be published.

Properties

PropertyDescriptionType
channelsThe names of the channels to publish the messages toString[]
messagesAn array of Message objectsMessage[]

BatchResult

A BatchResult contains information about the results of a batch operation.

Properties

PropertyDescriptionType
successCountThe number of successful operations in the requestNumber
failureCountThe number of unsuccessful operations in the requestNumber
messagesAn array of results for the batch operation (for example, an array of BatchPublishSuccessResult or BatchPublishFailureResult for a channel batch publish request)Object[]

BatchPublishSuccessResult

A BatchPublishSuccessResult contains information about the result of successful publishes to a channel requested by a single BatchPublishSpec.

Properties

PropertyDescriptionType
channelThe name of the channel the message(s) was published toString
messageIdA unique ID prefixed to the Message.id of each published messageString

BatchPublishFailureResult

A BatchPublishFailureResult contains information about the result of unsuccessful publishes to a channel requested by a single BatchPublishSpec.

Properties

PropertyDescriptionType
channelThe name of the channel the message(s) failed to be published toString
errorDescribes the reason for which the message(s) failed to publish to the channel as an ErrorInfo objectErrorInfo

BatchPresenceSuccessResult

A BatchPresenceSuccessResult contains information about the result of a successful batch presence request for a single channel.

Properties

PropertyDescriptionType
channelThe channel name the presence state was retrieved forString
presenceAn array of PresenceMessage describing members present on the channelPresenceMessage[]

BatchPresenceFailureResult

A BatchPresenceFailureResult contains information about the result of an unsuccessful batch presence request for a single channel.

Properties

PropertyDescriptionType
channelThe channel name the presence state failed to be retrieved forString
errorDescribes the reason for which presence state could not be retrieved for the channel as an ErrorInfo objectErrorInfo
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