Channel Groups API for PubNub Objective-C SDK

Channel Groups allows PubNub developers to bundle thousands of channels into a group that can be identified by name. These Channel Groups can then be subscribed to, receiving data from the many back-end channels the channel group contains.

Learn more about our Channel Groups here.

Channel Group operations

You can't publish to a Channel Group. You can only subscribe to it. To publish within Channel Group, you need to publish to each channel individually.

Adding Channels

Requires Stream Controller add-on

This method requires that the Stream Controller add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

Description

This function adds a channel to a channel group.

Method(s)

Adding Channels is accomplished by using the following method(s) in the Objective-C SDK:

- (void)addChannels:(NSArray<NSString *> *)channels toGroup:(NSString *)group withCompletion:(nullable PNChannelGroupChangeCompletionBlock)block;

Parameter	Type	Required	Description
channels	NSArray	Yes	List of channel names which should be added to the group.
group	NSString	Yes	Name of the group into which channels should be added.
block	PNChannelGroupChangeCompletionBlock	No	Channels addition process completion block which pass only one argument - request processing status to report about how data pushing was successful or not.

Basic Usage

Adding Channels

NSString *channelGroup = @"family";

[self.client addChannels: @[@"wife"] toGroup:channelGroup
          withCompletion:^(PNAcknowledgmentStatus *status) {

    if (!status.isError) {

        // Handle successful channels list modification for group.
    }
    else {

        /**
         Handle channels list modification for group error. Check 'category' property
         to find out possible reason because of which request did fail.
         Review 'errorData' property (which has PNErrorData data type) of status
         object to get additional information about issue.

show all 19 lines

Response

Response objects which is returned by client when Add Channels to Group API is used:

@interface PNAcknowledgmentStatus : PNErrorStatus

@end

Listing Channels

Requires Stream Controller add-on

This method requires that the Stream Controller add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

Description

This function lists all the channels of the channel group.

Method(s)

Listing Channels is accomplished by using the following method(s) in the Objective-C SDK:

- (void)channelsForGroup:(NSString *)group withCompletion:(PNGroupChannelsAuditCompletionBlock)block;

Parameter	Type	Required	Description
group	NSString	Yes	Name of the group from which channels should be fetched.
block	PNClientChannelsForGroupRequestHandlingBlock	Yes	Channels audition process completion block which pass two arguments: result - in case of successful request processing data field will contain results of channel groups channels audition operation; status - in case if error occurred during request processing.

Basic Usage

Listing Channels

NSString *channelGroup = @"family";

[self.client channelsForGroup:channelGroup withCompletion:^(PNChannelGroupChannelsResult *result,
                                                            PNErrorStatus *status) {

    if (!status) {

        // Handle downloaded list of chanels using: result.data.channels
    }
    else {

        /**
         Handle channels for group audition error. Check 'category' property
         to find out possible reason because of which request did fail.
         Review 'errorData' property (which has PNErrorData data type) of status
         object to get additional information about issue.

show all 19 lines

Response

Response objects which is returned by client when Add Channels to Group API is used:

@interface PNChannelGroupChannelsData : PNServiceData

// Registered channels within channel group.
@property (nonatomic, readonly, strong) NSArray<NSString *> *channels;

@end

@interface PNChannelGroupChannelsResult : PNResult

// Stores reference on channel group's channels list audit request processing information.
@property (nonatomic, nonnull, readonly, strong) PNChannelGroupChannelsData *data;

@end

Removing Channels

Requires Stream Controller add-on

This method requires that the Stream Controller add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

Description

This function removes the channels from the channel group.

Method(s)

Removing Channels is accomplished by using the following method(s) in the Objective-C SDK:

- (void)removeChannels:(NSArray<NSString *> *)channels fromGroup:(NSString *)group withCompletion:(nullable PNChannelGroupChangeCompletionBlock)block;

Parameter	Type	Required	Description
channels	NSArray	Yes	List of channel names which should be removed from group. If empty list passed whole channel group will be removed.
group	NSString	Yes	Channel group from which channels should be removed.
block	PNChannelGroupChangeCompletionBlock	No	Channels removal process completion block which pass only one argument - request processing status to report about how data pushing was successful or not.

Basic Usage

Removing channels

NSString *channelGroup = @"family";

[self.client removeChannels:@[@"son"] fromGroup:channelGroup
             withCompletion:^(PNAcknowledgmentStatus *status) {

    if (!status.isError) {

        // Handle successful channels list modification for group.
    }
    else {

        /**
         Handle channels list modification for group error. Check 'category' property
         to find out possible reason because of which request did fail.
         Review 'errorData' property (which has PNErrorData data type) of status
         object to get additional information about issue.

show all 19 lines

Response

Response objects which is returned by client when Remove Channels to Group API is used:

@interface PNAcknowledgmentStatus : PNErrorStatus

@end

Deleting Channel Group

Requires Stream Controller add-on

This method requires that the Stream Controller add-on is enabled for your key in the Admin Portal. Read the support page on enabling add-on features on your keys.

Description

This function removes the channel group.

Method(s)

Deleting Channel Group is accomplished by using the following method(s) in the Objective-C SDK:

- (void)removeChannelsFromGroup:(NSString *)group withCompletion:(nullable PNChannelGroupChangeCompletionBlock)block;

Parameter	Type	Required	Description
group	NSString	Yes	Name of the group from which all channels should be removed.
block	PNChannelGroupChangeCompletionBlock	No	Channel group removal process completion block which pass only one argument - request processing status to report about how data pushing was successful or not.

Basic Usage

Deleting Channel Group :

NSString *channelGroup = @"family";

[self.client removeChannelsFromGroup:channelGroup withCompletion:^(PNAcknowledgmentStatus *status) {

    if (!status.isError) {

        // Handle successful channel group removal.
    }
    else {

        /**
         Handle channel group removal error. Check 'category' property
         to find out possible reason because of which request did fail.
         Review 'errorData' property (which has PNErrorData data type) of status
         object to get additional information about issue.

         Request can be resent using: [status retry];

show all 18 lines

Response

Response objects which is returned by client when Remove Channel Group API is used:

@interface PNAcknowledgmentStatus : PNErrorStatus

@end