# Message history (Beta) (/en/realtime-media/rtm/build/send-and-receive-messages/message-history/ios)

> For AI agents: see the complete documentation index at [llms.txt](/llms.txt).

The Signaling message history feature allows you to store messages when publishing them to a channel. For example, if a user joins a channel midway through a conversation, you can retrieve messages that were published before the user joined. You can configure the message retention period for each project, ranging from 1 day to permanent storage.

    When a message is published, it is stored using the channel name and the message timestamp. You can use this information to retrieve historical messages.

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        The historical message feature is currently available for User Channels and Message Channels, but not for Stream Channels.
      </CalloutDescription>
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    ## Prerequisites [#prerequisites-2]

    Before implementing this feature, ensure that you have:

    * Integrated the Signaling SDK in your project, and implemented the framework functionality from the [SDK quickstart](../../index) page.
    * Enabled the message history feature by contacting [support@agora.io](mailto\:support@agora.io). You can request a storage duration of 1, 7, 30, 90, or 365 days, or opt for permanent storage.

      <CalloutContainer type="info">
        <CalloutDescription>
          Changes to storage duration only affect future messages.
        </CalloutDescription>
      </CalloutContainer>

    ## Implement message history [#implement-message-history-2]

    This section shows how to store and retrieve messages from history.

    ### Store messages [#store-messages-2]

    To store a message on the server, set `setStoreInHistory` to `true` in the `publish()` method. The following example shows the minimum code to store a message published to a message channel:

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        ```swift
        let message = "Hello Agora!"
        let channel = "your_channel"

        let publishOption = AgoraRtmPublishOptions()
        publishOption.storeInHistory = true;

        rtmKit.publish(channelName: channel, message: message, option: publishOption, completion: { res, error in
            if error != nil {
                print("\(error?.operation) failed! error reason is \(error?.reason)")
            } else {
                print("success")
            }
        })
        ```
      </CodeBlockTab>

      <CodeBlockTab value="Objc">
        ```objc
        NSString* message = @"Hello Agora!";
        NSString* channel = @"your_channel";

        AgoraRtmPublishOptions* publish_option = [[AgoraRtmPublishOptions alloc] init];
        publish_option.storeInHistory = true;

        [_kit publish:channel message:message option:publish_option completion:^(AgoraRtmCommonResponse * _Nullable response, AgoraRtmErrorInfo * _Nullable errorInfo) {
            if (errorInfo == nil) {
                NSLog(@"publish success!!");
            } else {
                NSLog(@"publish failed, errorCode %d, reason %@", errorInfo.errorCode, errorInfo.reason);
            }
        }];
        ```
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    To store a message in the history of a user channel, use the same parameter:

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        ```swift
        let message = "Hello Agora!"
        let user = "Tony"

        let publishOption = AgoraRtmPublishOptions()
        publishOption.channelType = .user
        publishOption.storeInHistory = true;

        rtmKit.publish(channelName: user, message: message, option: publishOption, completion: { res, error in
            if error != nil {
                print("\(error?.operation) failed! error reason is \(error?.reason)")
            } else {
                print("success")
            }
        })
        ```
      </CodeBlockTab>

      <CodeBlockTab value="Objc">
        ```objc
        NSString* message = @"Hello Agora!";
        NSString* user = @"Tony";

        AgoraRtmPublishOptions* publish_option = [[AgoraRtmPublishOptions alloc] init];
        publish_option.channelType = AgoraRtmChannelTypeUser;
        publish_option.storeInHistory = true;

        [_kit publish:user message:message option:publish_option completion:^(AgoraRtmCommonResponse * _Nullable response, AgoraRtmErrorInfo * _Nullable errorInfo) {
            if (errorInfo == nil) {
                NSLog(@"publish success!!");
            } else {
                NSLog(@"publish failed, errorCode %d, reason %@", errorInfo.errorCode, errorInfo.reason);
            }
        }];
        ```
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    ### Retrieve messages [#retrieve-messages-2]

    The SDK provides the `getMessages()` method to retrieve up to 100 history messages at a time. You can filter messages by setting the `start` and `end` parameters to define a time range. To retrieve only the most recent messages, such as those sent between the last offline time and now, set only the `end` parameter.

    The following example retrieves the latest 50 messages sent before a specific time:

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        ```swift
        var option = AgoraRtmGetHistoryMessagesOptions()
         option.messageCount = 50
         option.end = 1688978391800

        rtmKit.getHistory()?.getMessages(channelName: "channel_name", channelType: .message, options: option, completion: { response, error in
            if response != nil {
                print("total message count is: \(response!.messageList.count)")
                    for msg in response!.messageList {
                        print("publisher: \(msg.publisher)message content: \(msg.message.stringData!)time stamp: \(msg.timestamp)")
                    }
                    print("new start: \(response!.newStart)")
            } else {
                print("get history message failed")
            }
        })
        ```
      </CodeBlockTab>

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        ```objc
        AgoraRtmGetHistoryMessagesOptions *option = [[AgoraRtmGetHistoryMessagesOptions alloc] init];
        option.messageCount = 50;
        option.end = 1688978391800;

        [_kit getMessages:@"channel_name"
                    channelType:AgoraRtmChannelTypeMessage
                        options:option
                     completion:^(AgoraRtmGetHistoryMessagesResponse *response, NSError *error) {
            if (response != nil) {
                NSLog(@"total message count is: %lu", (unsigned long)response.messageList.count);

                for (AgoraRtmMessage *msg in response.messageList) {
                    NSLog(@"publisher: %@message content: %@time stamp: %lld", msg.publisher, msg.message.stringData, msg.timestamp);
                }

                NSLog(@"new start: %@", response.newStart);
            } else {
                NSLog(@"get history message failed: %@", error.localizedDescription);
            }
        }];
        ```
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    The `response` includes a `newStart` field, which indicates whether there are unread messages in the history:

    * If `newStart` is `0`, all messages have been retrieved.
    * If `newStart` is not `0`, use this value as the new `start` parameter in the next `getMessages()` call to continue retrieving messages.

    The following use-cases show how to specify the `start` and `end` parameters to retrieve messages in a specific range:

    #### Retrieve before a start timestamp [#retrieve-before-a-start-timestamp-2]

    | Parameter | Behavior                                                                                |
    | --------- | --------------------------------------------------------------------------------------- |
    | `start`   | Returns messages sent before the specified timestamp. The timestamp itself is excluded. |

    ```text
    Timeline:
    [Older messages] ------------ start timestamp ------------ [Newer messages]
    [             ←-- n messages]
    ```

    #### Retrieve messages up to an end timestamp [#retrieve-messages-up-to-an-end-timestamp-2]

    | Parameter | Behavior                                                                             |
    | --------- | ------------------------------------------------------------------------------------ |
    | `end`     | Returns the n most recent messages sent up to and including the specified timestamp. |

    ```text
    Timeline:
    [Older messages] ------------ end timestamp ------------ [Newer messages]
                                           [  ←-- n messages]
    ```

    #### Retrieve messages between two timestamps [#retrieve-messages-between-two-timestamps-2]

    | Parameter | Behavior                                                  |
    | --------- | --------------------------------------------------------- |
    | `start`   | Returns messages sent before this timestamp (excluded).   |
    | `end`     | Returns messages sent up to and including this timestamp. |

    ```text
    Timeline:
    [Older messages] ---- end timestamp ------------ start timestamp ---- [Newer messages]
                                   [ ←-- n messages]
    ```