feat: add RestClient#batchPresence specs

textile/features.textile

@@ -162,6 +162,7 @@ h3(#restclient). RestClient
 * @(RSC22)@ @RestClient#batchPublish@ function:
 ** @(RSC22a)@ Takes a @BatchPublishSpec@ or an array of @BatchPublishSpec@s and sends then in a POST request to @/messages@ with the @newBatchResponse@ query param set to "true".
 ** @(RSC22b)@ Returns an array of @BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>@s. Optionally, in languages where this is idiomatic, an overload may be implemented whereby the method can be called with a single @BatchPublishSpec@ and return a single @BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>@. This is not a feature of the REST API, whose response will still be an array, so if implementing this overload, the SDK will have to extract the element from the array.
+* @(RSC23)@ @RestClient#batchPresence@ function takes an array of channel name strings and sends them as a comma separated string in the @channels@ query parameter in a GET request to @/presence@ with the @newBatchResponse@ query param set to "true", returning a @BatchResult<BatchPresenceSuccessResult | BatchPresenceFailureResult>@ object.
 
 h3(#rest-auth). Auth
 
@@ -1531,6 +1532,20 @@ h4. BatchPublishFailureResult
 ** @(BPF2a)@ @channel@ string - the name of the channel
 ** @(BPF2b)@ @error@ @ErrorInfo@ - an @ErrorInfo@ indicating the reason the message(s) failed to publish
 
+h4. BatchPresenceSuccessResult
+
+* @(BGR1)@ Contains information about the result of a successful batch presence request for a single channel
+* @(BGR2)@ The attributes of @BatchPresenceSuccessResult@ consist of:
+** @(BGR2a)@ @channel@ string - the name of the channel
+** @(BGR2b)@ @presence@ @PresenceMessage[]@ - an array containing all members present on the channel if the request succeeded
+
+h4. BatchPresenceFailureResult
+
+* @(BGF1)@ Contains information about the result of an unsuccessful batch presence request for a single channel
+* @(BGF2)@ The attributes of @BatchPresenceFailureResult@ consist of:
+** @(BGF2a)@ @channel@ string - the name of the channel
+** @(BGF2b)@ @error@ @ErrorInfo@ - @ErrorInfo@ indicating the reason the presence request failed for the given channel, if unsuccessful
+
 h4. MessageFilter
 * @(MFI1)@ Supplies filter options to subscribe as defined in #RTL22
 * @(MFI2)@ Contains the following attributes:
@@ -1748,6 +1763,7 @@ class RestClient: // RSC*
   time() => io Time // RSC16
   batchPublish(BatchPublishSpec) => io BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult> // RSC22
   batchPublish(BatchPublishSpec[]) => io BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>[] // RSC22
+  batchPresence(string[]) => io BatchResult<BatchPresenceSuccessResult | BatchPresenceFailureResult>[] // RSC23
 
 class RealtimeClient: // RTC*
   constructor(keyOrTokenStr: String) // RTC12
@@ -1777,6 +1793,7 @@ class RealtimeClient: // RTC*
   time() => io Time // RTC6
   batchPublish(BatchPublishSpec) => io BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult> // RSC22
   batchPublish(BatchPublishSpec[]) => io BatchResult<BatchPublishSuccessResult | BatchPublishFailureResult>[] // RSC22
+  batchPresence(string[]) => io BatchResult<BatchPresenceSuccessResult | BatchPresenceFailureResult>[] // RSC23
 
 class ClientOptions: // TO*
   embeds AuthOptions // This is not currently documented in the spec and needs to be – see https://github.com/ably/docs/issues/1476
@@ -2380,6 +2397,14 @@ class BatchPublishSuccessResult:
 class BatchPublishFailureResult:
   channel: string // BPF2a
   error: ErrorInfo // BPF2c
+
+class BatchPresenceSuccessResult:
+  channel: string // BGR2a
+  presence?: [PresenceMessage] // BGR2b
+
+class BatchPresenceFailureResult
+  channel: string // BGF2a
+  error?: ErrorInfo // BGF2b
 </pre>
 
 h2(#old-specs). Old specs