Message Persistence API for PubNub C# SDK

The PubNub Message Persistence Service provides real-time access to history for all messages published to PubNub. Each published message is timestamped to the nearest 10 nanoseconds, and is stored across multiple availability zones in several geographical data center locations. Stored messages can be encrypted with AES-256 message encryption, ensuring that they are not readable while stored on PubNub's network.

Messages can be stored for a configurable duration or forever, as controlled by the retention policy that is configured on your account. The following options are available: 1, 3, 5, 7, 15, or 30 days, and Forever.

Fetch History

Requires Message Persistence add-onRequires that the Message Persistence add-on is enabled for your key. See this page on enabling add-on features on your keys:
https://support.pubnub.com/hc/en-us/articles/360051974791-How-do-I-enable-add-on-features-for-my-keys-

Description

This function fetches historical messages from one or multiple channels. The includeMessageActions flag also allows you to fetch message actions along with the messages.

It's possible to control how messages are returned and in what order.

if you specify only the start parameter (without end), you will receive messages that are older than the start timetoken
if you specify only the end parameter (without start), you will receive messages from that end timetoken and newer
if you specify values for both start and end parameters, you will retrieve messages between those timetokens (inclusive of the end value)

You will receive a maximum of 100 messages for a single channel or 25 messages for multiple channels (up to 500). If more messages meet the timetoken criteria, make iterative calls while adjusting the start timetoken to fetch the entire list of messages from storage.

Method(s)

To run Fetch History, you can use the following method(s) in the C# V4 SDK:

pubnub.FetchHistory().Channels(string[]).IncludeMeta(bool).IncludeMessageType(bool).IncludeUUID(bool).IncludeMessageActions(bool).Reverse(bool).Start(int).End(int).MaximumPerChannel(int).QueryParam(Dictionary<string, object>)

Parameter	Type	Required	Description
`Channels`	string[]	Yes	Specifies `channel` to return history messages from. Maximum of 500 channels are allowed.
`IncludeMeta`	bool	Optional	Whether meta (passed when Publishing the message) should be included in response or not.
`IncludeMessageType`	bool	Optional	Pass `true` to receive the message type with each history message. Default is `true`.
`IncludeUUID`	bool	Optional	Pass `true` to receive the publisher `uuid` with each history message. Default is `true`.
`IncludeMessageActions`	bool	Optional	The flag denoting to retrieve history messages with `message` actions. If `true`, the method is limited to one channel only. Default is `false`
`Reverse`	bool	Optional	Setting to `true` will traverse the time line in reverse starting with the oldest message first.
`Start`	long	Optional	Timetoken delimiting the `start` of time slice (exclusive) to pull messages from.
`End`	long	Optional	Timetoken delimiting the `end` of time slice (inclusive) to pull messages from.
`MaximumPerChannel`	int	Optional	Specifies the number of historical messages to return. Default and maximum is 100 for a single channel, 25 for multiple channels, and 25 if `IncludeMessageActions` is `true`.
`QueryParam`	Dictionary<string, object>	Optional	QueryParam accepts a Dictionary object, the keys and values are passed as the query string parameters of the URL called by the API.
`Execute`	PNCallback	Yes	`PNCallback` of type `PNFetchHistoryResult`.
`ExecuteAsync`	None	Optional	Returns `PNResult<PNFetchHistoryResult>`.

Truncated response

If you fetch messages with messages actions, the number of messages in the response may be truncated when internal limits are hit. If the response is truncated, a more property will be returned with additional parameters. Send iterative calls to history adjusting the parameters to fetch more messages.

Basic Usage

Retrieve the last message on a channel:

PNResult<PNFetchHistoryResult> fetchHistoryResponse = await pubnub.FetchHistory()
    .Channels(new string[] { "my_channel" })
    .IncludeMeta(true)
    .MaximumPerChannel(25)
    .ExecuteAsync();

Returns

{
    "Messages":
        {
            "my_channel":
            [{
                "Timetoken":15717278253295153,
                "Entry":"sample message",
                "Meta":"",
                "Uuid":"user-1",
                "MessageType":null,
                "Actions":null
            }]
        },
    "More":null
}

Other Examples

Retrieve the last 25 messages on a channel synchronously:

pubnub.FetchHistory()
    .Channels(new string[] { "my_channel" })
    .IncludeMeta(true)
    .MaximumPerChannel(25)
    .Execute(new PNFetchHistoryResultExt((result, status) =>
    {

    }));

Delete Messages from History

Description

Removes the messages from the history of a specific channel.

Note

There is a setting to accept delete from history requests for a key, which you must enable by checking the Enable Delete-From-History checkbox in the key settings for your key in the Admin Portal.

Requires Initialization with secret key.

Method(s)

To Delete Messages from History you can use the following method(s) in the C# V4 SDK.

pubnub.DeleteMessages().Channel(string).Start(long).End(long).QueryParam(Dictionary<string,object>)

Parameter	Type	Required	Description
`Channel`	string	Yes	Specifies `channel` messages to be deleted from history.
`Start`	long	Optional	Timetoken delimiting the `Start` of time slice (inclusive) to delete messages from.
`End`	long	Optional	`Timetoken` delimiting the End of time slice (exclusive) to delete messages from.
`QueryParam`	Dictionary<string, object>	Optional	Dictionary `object` to pass name/value pairs as query `string` params with PubNub URL request for debug purpose.
`Async`	PNCallback	Deprecated	`PNCallback` of type `PNDeleteMessageResult`.
`Execute`	PNCallback	Yes	`PNCallback` of type `PNDeleteMessageResult`.
`ExecuteAsync`	None	Optional	Returns `PNResult<PNDeleteMessageResult>`.

Basic Usage

PNResult<PNDeleteMessageResult> delMsgResponse = await pubnub.DeleteMessages()
    .Channel("history_channel")
    .Start(15088506076921021)
    .End(15088532035597390)
    .ExecuteAsync();

PNDeleteMessageResult delMsgResult = delMsgResponse.Result;
PNStatus status = delMsgResponse.Status;

if (status != null && status.Error)
{
    //Check for any error
    Console.WriteLine(status.ErrorData.Information);
}
else if (delMsgResult != null)
{
    //Expect empty object
    Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(delMsgResult));
}

Returns

The DeleteMessages() operation returns a PNResult<PNDeleteMessageResult> which returns empty PNDeleteMessageResult object.

Other Examples

Delete messages sent in a particular timeframe

pubnub.DeleteMessages()
    .Channel("history_channel")
    .Start(15088506076921021)
    .End(15088532035597390)
    .Execute(new PNDeleteMessageResultExt(
        (result, status) => {
            if (status != null && status.Error) {
                //Check for any error
                Console.WriteLine(status.ErrorData.Information);
            }
            else if (result != null) {
                //Expect empty object
                Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(result));
            }
        }
    ));

Delete specific message from history
To delete a specific message, pass the publish timetoken (received from a successful publish) in the End parameter and timetoken +/- 1 in the Start parameter. e.g. if 15526611838554310 is the publish timetoken, pass 15526611838554309 in Start and 15526611838554310 in End parameters respectively as shown in the following code snippet.

PNResult<PNDeleteMessageResult> delMsgResponse = await pubnub.DeleteMessages()
    .Channel("history_channel")
    .Start(15526611838554310)
    .End(15526611838554309)
    .ExecuteAsync();

PNDeleteMessageResult delMsgResult = delMsgResponse.Result;
PNStatus status = delMsgResponse.Status;

if (status != null && status.Error)
{
    //Check for any error
    Console.WriteLine(status.ErrorData.Information);
}
else if (delMsgResult != null)
{
    //Expect empty object
    Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(delMsgResult));
}

Message Counts

Description

Returns the number of messages published on one or more channels since a given time. The count returned is the number of messages in history with a timetoken value greater than or equal to than the passed value in the ChannelsTimetokenparameter.

Note

For keys with unlimited message retention enabled, this method considers only messages published in the last 30 days.

Method(s)

You can use the following method(s) in the C# V4 SDK:

pubnub.MessageCounts().Channels(string[]).ChannelsTimetoken(long[]).QueryParam(Dictionary<string, object>)

Parameter	Type	Required	Description
`Channels`	string[]	Yes	The `channels` to fetch the message count
`ChannelsTimetoken`	long[]	Yes	Array of `timetokens`, in order of the channels list. Specify a single `timetoken` to apply it to all channels. Otherwise, the list of `timetokens` must be the same length as the list of channels, or the function returns a `PNStatus`with an error flag.
`Async`	PNCallback	Deprecated	PNCallback of type `PNMessageCountResult`.
`Execute`	PNCallback	Yes	PNCallback of type `PNMessageCountResult`.
`ExecuteAsync`	None	Optional	Returns `PNResult<PNMessageCountResult>`.

Basic Usage

PNResult<PNMessageCountResult> msgCountResponse = await pubnub.MessageCounts()
    .Channels(new string[] { "message_count_channel" })
    .ChannelsTimetoken(new long[] { 15088506076921021 })
    .ExecuteAsync();

PNMessageCountResult msgCountResult = msgCountResponse.Result;
PNStatus status = msgCountResponse.Status;

if (status != null && status.Error)
{
    //Check for any error
    Console.WriteLine(status.ErrorData.Information);
}
else
{
    Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(msgCountResult));
}

Returns

The operation returns a PNResult<PNMessageCountResult> which contains the following operations:

Property Name	Type	Description
`Result`	PNMessageCountResult	Returns a `PNMessageCountResult` object.
`Status`	PNStatus	Returns a `PNStatus` object

PNMessageCountResult contains the following properties:

Property Name	Type	Description
`Channels`	Dictionary<string, long>	Collection of `channels` along with the messages count. `channels` without messages have a count of 0. `channels` with 10,000 messages or more have a count of 10000.

Other Examples

Retrieve count of messages for a single channel

pubnub.MessageCounts()
    .Channels(new string[] { "message_count_channel" })
    .ChannelsTimetoken(new long[] { 15088506076921021 })
    .Execute(new PNMessageCountResultExt(
    (result, status) => {
        if (status != null && status.Error)
        {
            //Check for any error
            Console.WriteLine(status.ErrorData.Information);
        }
        else
        {
            Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(result));
        }
    }));

Retrieve count of messages using different timetokens for each channel

PNResult<PNMessageCountResult> msgCountResponse = await pubnub.MessageCounts()
    .Channels(new string[] { "message_count_channel", "message_count_channel2" })
    .ChannelsTimetoken(new long[] { 15088506076921021, 15088506076921131 })
    .ExecuteAsync();

PNMessageCountResult msgCountResult = msgCountResponse.Result;
PNStatus status = msgCountResponse.Status;

if (status != null && status.Error)
{
    //Check for any error
    Console.WriteLine(status.ErrorData.Information);
}
else
{
    Console.WriteLine(pubnub.JsonPluggableLibrary.SerializeToJsonString(msgCountResult));
}

History (deprecated)

Note

This method is deprecated. Use fetch history instead.

Description

This function fetches historical messages of a channel.

It is possible to control how messages are returned and in what order, for example you can:

Search for messages starting on the newest end of the timeline (default behavior - Reverse = false)
Search for messages from the oldest end of the timeline by setting Reverse to true.
Page through results by providing a Start OR End timetoken.
Retrieve a slice of the time line by providing both a Start AND End timetoken.
Limit the number of messages to a specific quantity using the Count parameter.

Start & End parameter usage clarity:

If only the Start parameter is specified (without End), you will receive messages that are older than and up to that Start timetoken value. If only the End parameter is specified (without Start) you will receive messages that match that End timetoken value and newer Specifying values for both Start and End parameters will return messages between those timetoken values (inclusive on the End value). Keep in mind that you will still receive a maximum of 100 messages even if there are more messages that meet the timetoken values. Iterative calls to history adjusting the Start timetoken is necessary to page through the full set of results if more than 100 messages meet the timetoken values.

Method(s)

To run History you can use the following method(s) in the C# V4 SDK:

pubnub.History().Channel(string).IncludeMeta(bool).Reverse(bool).IncludeTimetoken(bool).Start(long).End(long).count(int).QueryParam(Dictionary<string,object>)

Parameter	Type	Required	Description
`Channel`	string	Yes	Specifies `Channel`to return history messages from.
`IncludeMeta`	bool	Optional	Whether meta (passed when Publishing the message) should be included in response or not.
`Reverse`	bool	Optional	Setting to `true` will traverse the time line in reverse starting with the oldest message first.
`IncludeTimetoken`	bool	Optional	Whether event dates `timetokens` should be included in response or not.
`Start`	long	Optional	Timetoken delimiting the `Start` of time slice (exclusive) to pull messages from.
`End`	long	Optional	Timetoken delimiting the `End` of time slice (inclusive) to pull messages from.
`Count`	int	Optional	Specifies the number of historical messages to return.
`QueryParam`	Dictionary<string, object>	Optional	Dictionary `object` to pass name/value pairs as query `string` params with PubNub URL request for debug purpose.
`Async`	PNCallback	Deprecated	`PNCallback` of type `PNHistoryResult`.
`Execute`	PNCallback	Yes	`PNCallback` of type `PNHistoryResult`.
`ExecuteAsync`	None	Optional	Returns `PNResult<PNHistoryResult>`.

Using the `reverse` parameter:

Messages are always returned sorted in ascending time direction from history regardless of Reverse. The Reverse direction matters when you have more than 100 (or Count, if it's set) messages in the time interval, in which case Reverse determines the end of the time interval from which it should start retrieving the messages.

Basic Usage

Retrieve the last 100 messages on a channel:

PNResult<PNHistoryResult> historyResponse = await pubnub.History()
    .Channel("history_channel") // where to fetch history from
    .Count(100) // how many items to fetch
    .ExecuteAsync();

Returns

The History() operation returns a PNResult<PNHistoryResult> which contains the following properties:

Property Name	Type	Description
`Result`	PNHistoryResult	Returns a `PNHistoryResult` object.
`Status`	PNStatus	Returns a `PNStatus` object.

PNHistoryResult which contains the following properties:

Property Name	Type	Description
`Messages`	List	List of messages of type `PNHistoryItemResult`. See PNHistoryItemResult for more details.
`StartTimetoken`	long	Start `timetoken`.
`EndTimetoken`	long	End `timetoken`.

PNHistoryItemResult:

Property Name	Type	Description
`Timetoken`	long	`Timetoken` of the message.
`Entry`	object	Message.

Other Examples

Retrieve the last 100 messages on a channel synchronously:

pubnub.History()
    .Channel("history_channel") // where to fetch history from
    .Count(100) // how many items to fetch
    .Execute(new PNHistoryResultExt(
        (result, status) => {
        }
    ));

Use History() to retrieve the three oldest messages by retrieving from the time line in reverse:

PNResult<PNHistoryResult> historyResponse = await pubnub.History()
    .Channel("my_channel") // where to fetch history from
    .Count(3) // how many items to fetch
    .Reverse(true) // should go in reverse?
    .ExecuteAsync();

Response:

{
    "Messages":[
        {
            "Timetoken": 0,
            "Entry": "Pub1"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub2"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub3"
        }
    ],
    "StartTimeToken": 13406746729185766,
    "EndTimeToken": 13406746780720711
}

Use History() to retrieve messages newer than a given timetoken by paging from oldest message to newest message starting at a single point in time (exclusive):

PNResult<PNHistoryResult> historyResponse = await pubnub.History()
    .Channel("my_channel") // where to fetch history from
    .Start(13847168620721752L) // first timestamp
    .Reverse(true) // should go in reverse?
    .ExecuteAsync();

Response:

{
    "Messages":[
        {
            "Timetoken": 0,
            "Entry": "Pub3"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub4"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub5"
        }
    ],
    "StartTimeToken": 13406746780720711,
    "EndTimeToken": 13406746845892666
}

Use History() to retrieve messages until a given timetoken by paging from newest message to oldest message until a specific end point in time (inclusive):

PNResult<PNHistoryResult> historyResponse = await pubnub.History()
    .Channel("my_channel") // where to fetch history from
    .Count(100) // how many items to fetch
    .Start(-1) // first timestamp
    .End(13847168819178600L) // last timestamp
    .Reverse(true) // should go in reverse?
    .ExecuteAsync();

Response:

{
    "Messages":[
        {
            "Timetoken": 0,
            "Entry": "Pub3"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub4"
        },
        {
            "Timetoken": 0,
            "Entry": "Pub5"
        }
    ],
    "StartTimeToken": 13406746780720711,
    "EndTimeToken": 13406746845892666
}

History Paging Example

Usage!

You can call the method by passing 0 or a valid timetoken as the argument.

public class PubnubRecursiveHistoryFetcher {
    private static Pubnub pubnub;

    public abstract class CallbackSkeleton {
        public abstract void HandleResponse(PNHistoryResult result);
    }

    public PubnubRecursiveHistoryFetcher() {
        // NOTICE: for demo/demo pub/sub keys Message Persistence is disabled,
        // so use your pub/sub keys instead
        PNConfiguration pnConfiguration = new PNConfiguration pnConfiguration = new PNConfiguration(new UserId("myUniqueUserId"));
        pnConfiguration.SubscribeKey = "demo";
        pubnub = new Pubnub(pnConfiguration);
    }

    static public void Main() {
        PubnubRecursiveHistoryFetcher fetcher = new PubnubRecursiveHistoryFetcher();
        GetAllMessages(new DemoCallbackSkeleton());
    }

    public static void GetAllMessages(CallbackSkeleton callback) {
        GetAllMessages(-1L, callback);
    }

    public static void GetAllMessages(long startTimestamp, CallbackSkeleton callback) {
        CountdownEvent latch = new CountdownEvent(1);

        pubnub.History()
            .Channel("history_channel") // where to fetch history from
            .Count(100) // how many items to fetch
            .Start(startTimestamp) // first timestamp
            .Execute(new DemoHistoryResult(callback));
    }

    public class DemoHistoryResult : PNCallback<PNHistoryResult> {
        CallbackSkeleton internalCallback;
        public DemoHistoryResult(CallbackSkeleton callback) {
            this.internalCallback = callback;
        }
        public override void OnResponse(PNHistoryResult result, PNStatus status) {
            if (!status.Error && result != null && result.Messages != null && result.Messages.Count > 0) {
                Console.WriteLine(result.Messages.Count);
                Console.WriteLine("start:" + result.StartTimeToken.ToString());
                Console.WriteLine("end:" + result.EndTimeToken.ToString());

                internalCallback.HandleResponse(result);
                GetAllMessages(result.EndTimeToken, this.internalCallback);
            }
        }
    };

    public class DemoCallbackSkeleton : CallbackSkeleton {
        public override void HandleResponse(PNHistoryResult result) {
            //Handle the result
        }
    }
}

Include timetoken in history response:

PNResult<PNHistoryResult> historyResponse = await pubnub.History()
    .Channel("history_channel") // where to fetch history from
    .Count(100) // how many items to fetch
    .IncludeTimetoken(true) // include timetoken with each entry
    .ExecuteAsync();

Fetch History

Description

Method(s)

Truncated response

Basic Usage

Returns

Other Examples

Delete Messages from History

Description

Note

Method(s)

Basic Usage

Returns

Other Examples

Message Counts

Description

Note

Method(s)

Basic Usage

Returns

Other Examples

History (deprecated)

Note

Description

Start & End parameter usage clarity:

Method(s)

Using the reverse parameter:

Basic Usage

Returns

Other Examples

Usage!

Using the `reverse` parameter: