Manage server-side messages
Updated
Introduces how to use the Agora Chat SDK to retrieve messages from the server.
The Chat SDK stores historical messages on the chat server. When a chat user logs in from a different device, you can retrieve the historical messages from the server, so that the user can also browse these messages on the new device. Additionally, the Chat SDK supports adding tags to conversation, with a maximum of 20 tags allowed per conversation.
This page introduces how to use the Chat SDK to retrieve, delete, and tag messages and conversations.
Understand the tech
The Chat SDK uses ChatManager to retrieve historical messages from the server. The following are the core methods:
asyncFetchConversationsFromServer: Retrieves a list of conversations stored on the server.asyncFetchHistoryMessages: Retrieves historical messages of a conversation from the server according toFetchMessageOption, the parameter configuration class for retrieving historical messages.asyncPinConversation: Pins conversations.asyncFetchPinnedConversationsFromServer: Retrieves pinned conversations.asyncPinMessage: Pins a message in a conversation.asyncUnPinMessage: Unpin a message in a conversation.asyncGetPinnedMessagesFromServer: Get a list of pinned messages in a conversation.removeMessagesFromServer: One-way deletion of historical messages on the server based on message time or message ID.deleteConversationFromServer: Deletes conversations and their historical messages from the server.asyncAddConversationMark: Tags a conversation.asyncRemoveConversationMark: Removes a conversation tag.asyncGetConversationsFromServerWithCursor: Queries conversations from the server by a conversation tag.
The Chat SDK uses IChatManager to retrieve historical messages from the server. The following are the core methods:
GetConversationsFromServerWithPage: Retrieve conversations stored on the server with pagination.FetchHistoryMessagesFromServerBy: Retrieves historical messages of a conversation from the server according toFetchServerMessagesOption, the parameter configuration class for retrieving historical messages.PinConversation: Pins a conversation.GetConversationsFromServerWithCursor: Retrieves a list of pinned conversations.RemoveMessagesFromServer: Deletes historical messages from the server unidirectionally.DeleteConversationFromServer: Deletes conversations and their historical messages from the server.
Prerequisites
Before proceeding, ensure that you meet the following requirements:
- You have integrated the Chat SDK, initialized the SDK and implemented the functionality of registering accounts and login. For details, see Chat SDK quickstart.
- You understand the API call frequency limits as described in Limitations.
Implementation
This section shows how to implement retrieving conversations and messages.
Retrieve a list of conversations from the server
Call GetConversationsFromServerWithCursor to retrieve conversations from the server with pagination. You can set the pinOnly parameter in this method to determine whether to retrieve the list of pinned conversations:
- If
pinOnlyis set tofalse, you can retrieve the list of pinned and unpinned conversations. The SDK returns the conversation list in the reverse chronological order of when conversations are active (the timestamp of the last message in the conversation). - If
pinOnlyis set totrue, you can only retrieve the list of pinned conversations. The SDK returns the pinned conversations in the reverse chronological order of when they were pinned. Up to 50 pinned conversations can be retrieved.
In the conversation list, each conversation object contains the conversation ID, conversation type, whether the conversation is pinned, the pinned time (the value is 0 for an unpinned conversation), and the last message in the conversation. After the conversation list is retrieved from the server, the local conversation list will be updated accordingly. We recommend calling this method when the app is first installed, or when there is no conversation on the local device. Otherwise, you can call LoadAllConversations to retrieve conversations on the local device.
For each end user, the server stores 100 conversations by default. When this limit is exceeded, new conversations will start overwriting the old ones. If the entire message history in a conversation expires, the conversation becomes empty. When pulling the conversation list from the server, these empty conversations are not included by default. To include them, set Options#EnableEmptyConversation to true when initializing the SDK. In this case, empty conversations will occupy the conversations pull quota, regardless of whether they are needed when pulling. To change this, contact support@agora.io.
// limit: The number of conversations that you expect to get on each page. The value range is [1,50].
int limit = 10;
string cursor = "";
bool pinOnly = false; // `false`:Get the list of all conversations; `true`: Get the list of only pinned conversations.
SDKClient.Instance.ChatManager.GetConversationsFromServerWithCursor(pinOnly, cursor, limit, new ValueCallBack>(
onSuccess: (result) =>
{
// Traverse the obtained conversation list
foreach (var conv in result.Data)
{
}
// The cursor for the next request
string nextCursor = result.Cursor;
},
onError: (code, desc) =>
{
}
));Retrieve message history of the specified conversation
After retrieving conversations, you can retrieve historical messages from the server.
You can set the search direction to retrieve messages in the chronological or reverse chronological order of when the server receives them, the message type, the time period, the message sender, as well as whether to save the retrieved message to the local database.
If you have integrated Chat SDK after June 8, 2023, you can retrieve historical messages even before joining the Chat Group. For earlier implementations, contact support@agora.io to enable this.
The Agora Chat server stores the full message history for a certain period of time depending on your subscribed Chat plan. After an end user logs back into Agora Chat, the servers automatically send offline messages to them, that is, messages transmitted when that end user was offline. Offline messages are a subset of the full message history stored on Agora Chat server. Sending only a subset of messages prevents distributing too many messages to a single device, which can overwhelm it and slow down the end user login. Agora Chat server stores and manages these offline messages for every end user in the following way:
- 1 private chat: Store 500 offline messages by default;
- Chat Group: Store 200 offline messages by default;
- Chatroom: Doesn't store offline messages. However, by default, whenever an end user joins a chatroom, Agora Chat servers push the 10 latest messages/chatroom to them, and this number can be adjusted to 200 messages/chatroom without additional charges.
After the GA release of Agora Chat 1.3, you can log in to Agora Console and enable the chatroom message history retrieval feature. After that, Agora Chat servers will stop automatically pushing chatroom messages to new members and you can follow the guidance below to retrieve chatroom message history.
For users to receive more offline messages, use the client API or a webhook to sync with Agora Chat's server. End users can also store additional messages on their local database.
To ensure data reliability, we recommend retrieving less than 50 historical messages for each method call. To retrieve more than 50 historical messages, call this method multiple times. Once the messages are retrieved, the SDK automatically updates these messages in the local database.
We recommend that you retrieve 20 messages each time, with a maximum of 50. During paginated query, if the total number of messages that meet the query conditions is greater than the number of pageSize, the number of messages of pageSize will be returned. If it is less than the number of pageSize, the actual number will be returned. When the message query is completed, the number of returned messages is less than the number of pageSize.
Since SDK v1.4.0, for a single group conversation you can retrieve messages sent by specific members (rather than all members) by setting the FromIds list in FetchServerMessagesOption. FromIds replaces the deprecated From attribute.
Refer to the following code sample:
FetchServerMessagesOption option = new FetchServerMessagesOption();
option.IsSave = false;
option.Direction = MessageSearchDirection.UP;
// Since SDK v1.4.0, for a group conversation, set FromIds to retrieve messages sent by specific members.
option.FromIds = new List<string> { "id1", "id2" };
option.MsgTypes = new List();
option.MsgTypes.Add(MessageBodyType.TXT);
option.MsgTypes.Add(MessageBodyType.VIDEO);
option.StartTime = 1695720454000;
option.EndTime = 1695720554000;
SDKClient.Instance.ChatManager.FetchHistoryMessagesFromServerBy(conversationId, type, cursor, pageSize, option, new ValueCallBack>(
onSuccess: (result) =>
{
},
onError: (code, desc) =>
{
}
)) ;Search local messages sent by specific members
Since SDK v1.4.0, for a single conversation you can load messages from the local database that are sent by specific members.
Conversation conv = SDKClient.Instance.ChatManager.GetConversation(conversationId, convType);
conv.LoadMessagesWithScopeAndFromIds(keyword, timestamp, maxCount, fromIds, direction, scope, new ValueCallBack<List<Message>>(
onSuccess: (list) => { },
onError: (code, desc) => { }
));Search local conversations by keyword
Since SDK v1.4.0, you can call LoadConversationMessagesWithKeyword to search across all local conversations for messages that contain a keyword. The SDK returns the matching conversation IDs and message IDs, ordered by message timestamp in ascending or descending order according to the direction parameter.
SDKClient.Instance.ChatManager.LoadConversationMessagesWithKeyword(keywords, timestamp, from, direction, scope, new ValueCallBack<Dictionary<string, List<string>>>(
onSuccess: (result) => { },
onError: (code, desc) => { }
));Retrieve local messages by message ID
Since SDK v1.4.0, you can call LoadMessages to retrieve one or more messages from a single local conversation by message ID. To retrieve a single message, call LoadMessage.
List<string> messageIdList = new List<string> { "msgId1", "msgId2" };
SDKClient.Instance.ChatManager.LoadMessages(messageIdList, conversationId, new ValueCallBack<List<Message>>(
onSuccess: (messages) => { },
onError: (code, desc) => { }
));Pin a conversation
To keep track of an important conversation, you can pin it to the top of your conversation list. You can pin up to 50 conversations. The pinned state is stored on the server. In a multi-device login use-case, if you pin or unpin a conversation, other login devices will receive the CONVERSATION_PINNED or CONVERSATION_UNPINNED events.
Refer to the following code example to pin a conversation:
SDKClient.Instance.ChatManager.PinConversation(convId, isPinned, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Retrieve the pinned conversations from the server with pagination
End users can pin up to 50 conversations. After you call this API, the SDK returns the pinned conversations in the reverse chronological order of when they are pinned.
Agora Chat servers store a list of conversations that remain active in the past 7 days, regardless of Agora Chat package subscription. A conversation is considered active if it is pinned or there are new messages in a conversation.
Refer to the following code example to get a list of pinned conversations from the server with pagination:
// limit: The number of sessions returned per page. The value range is [1,50].
// cursor: The cursor position to start getting data.
int limit = 10;
string cursor = "";
bool pinOnly = true; // `false`: Get the list of all conversations; `true`: Get the list of only pinned conversations.
SDKClient.Instance.ChatManager.GetConversationsFromServerWithCursor(pinOnly, cursor, limit, new ValueCallBack>(
onSuccess: (result) =>
{
// Traverse the obtained conversation list
foreach (var conv in result.Data)
{
}
// The cursor for the next query
string nextCursor = result.Cursor;
},
onError: (code, desc) =>
{
}
));Pin a message
To pin a message to the top of a one-to-one chat, chat group, or chat room, call ChatManager#PinMessage and set the isPinned parameter to true. When the pinned status of a message changes, other members in the one-to-one chat, group or chat room conversation receive the IChatManagerDelegate#OnMessagePinChanged event. In the case of multi-device login, the updated top status is synchronized to other logged-in devices, and other devices receive the IChatManagerDelegate#OnMessagePinChanged event, respectively.
Multiple users can pin the same message to the top. The latest pinned message overwrites the earlier information. That is, the PinnedInfo user ID and pin time correspond to the last pinned message.
If the message is stored locally but deleted on the server due to expiration, the message fails to be pinned to the top.
For a single conversation, 20 messages can be pinned to the top by default.
bool isPinned = true;
SDKClient.Instance.ChatManager.PinMessage(msgId, isPinned, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Unpin a message
To unpin a message in a one-to-one chat, chat group, or chat room, call ChatManager#PinMessage and set the isPinned parameter to false. As with pinned messages, other members of the one-to-one chat, chat group or chat room receive the IChatManagerDelegate#OnMessagePinChanged event when the pinned message is unpinned. In the case of multi-device login, the updated pin status is synchronized to other logged-in devices, and other devices receive the IChatManagerDelegate#OnMessagePinChanged event, respectively.
Any user in a one-to-one chat, group or room can unpin a message, regardless of who pinned it. After unpinning a message, PinnedBy and PinnedAt in Message#PinnedInfo are returned empty and set to 0, respectively, and the message is no longer included in the pinned message list.
bool isPinned = false;
SDKClient.Instance.ChatManager.PinMessage(msgId, isPinned, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Get pinned messages in a single conversation
You can call ChatManager#GetPinnedMessagesFromServer to get the pinned messages from a single conversation from the server. The SDK returns messages in the reverse order of pinning.
If a message expires on the server or the user deletes it unilaterally from the server after pinning, such user will not be able to pull it when pulling roaming messages. However, this user and other users will be able to pull this message from the pinned message list.If the user withdraws a message after pinning, the message will be removed from the server; other users will not be able to pull it when they pull the pinned message list from the server.
SDKClient.Instance.ChatManager.GetPinnedMessagesFromServer(convId, new ValueCallBack>(
onSuccess: (list) => {
foreach (var it in list)
{
// Traverse the message list
}
},
onError: (code, desc) => {
}
));Get pinned details of a single message
You can call PinnedInfo to get the pinned details of a single message.
- If the message is pinned, this class returns the time of pinning and the user ID of the user who has pinned it.
- If the message is not pinned, then
PinnedByis returned empty andPinnedAtis set to0.
// ...
const msg: ChatMessage;
const info = await msg.getPinInfo;
// todo: Get the pin information of the messageDelete historical messages from the server unidirectionally
Call RemoveMessagesFromServer to delete historical messages one way from the server. You can remove a maximum of 50 messages from the server each time. Once the messages are deleted, you can no longer retrieve them from the server. The deleted messages are automatically removed from your local device. Other chat users can still get the messages from the server.
To use this function, you need to contact support@agora.io to enable it.
SDKClient.Instance.ChatManager.RemoveMessagesFromServer(convId, ctype, time, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));
SDKClient.Instance.ChatManager.RemoveMessagesFromServer(convId, ctype, msgList, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Delete conversations and related messages from the server unidirectionally
Call DeleteConversationFromServer to delete conversations and their historical messages unidirectionally from the server. After the conversations and messages are deleted from the server, you can no longer get them from the server. The deleted conversations still exist on your local device, but the messages are automatically removed from the device. Other chat users can still get the conversations and their historical messages from the server.
SDKClient.Instance.ChatManager.DeleteConversationFromServer(conversationId, conversationType, isDeleteServerMessages, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Tag a conversation
To tag a conversation, use the MarkConversations method. This method allows you to add tags to both local and server-side conversations, that is, set the isMark parameter to 'true'. Each conversation can have up to 20 tags. This feature applies only to private chats and chat groups.
After adding a tag, you can retrieve the tagged conversations from the server by calling the GetConversationsFromServerWithCursor method. The returned conversation objects will include the conversation tag, which you can obtain using the marks property.
If the server conversation list reaches its limit (default 100 conversations per user), inactive conversations will be deleted based on conversation activity (timestamp of the latest message). Consequently, the conversation tags of these deleted conversations will also be removed.
Adding tags to a conversation, such as stars, does not affect other logic of the conversation, such as the number of unread messages in it.
List list = new List();
list.Add("huanhuan");
bool isMarked = true;
SDKClient.Instance.ChatManager.MarkConversations(list, isMarked, (MarkType)mark, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Remove conversation tag
You can call MarkConversations and set the isMark parameter to 'false' to untag a conversation. Tags can be removed for up to 20 conversations at a time. Calling this method removes both the local and server-side tags.
List list = new List();
list.Add("huanhuan");
bool isMarked = false;
SDKClient.Instance.ChatManager.MarkConversations(list, isMarked, (MarkType)mark, new CallBack(
onSuccess: () =>
{
},
onError: (code, desc) =>
{
}
));Query conversations from the server by the conversation tag
You can use the GetConversationsFromServerWithCursor method to retrieve a list of conversations from the server based on the tag. The SDK returns the conversation list in reverse order of the conversation tag's timestamp. Each conversation object includes the following information:
- Conversation ID
- Conversation type
- Pinned status (whether it is pinned or not)
- Pin time (For an unpinned conversation, the value is 0)
- Conversation tag
- Latest message
After fetching the conversation list from the server, the local conversation list is updated accordingly:
SDKClient.Instance.ChatManager.GetConversationsFromServerWithCursor((MarkType)mark, cursor, limit, new ValueCallBack>(
onSuccess: (result) =>
{
foreach (var conv in result.Data)
{
//Iterate over the sessions in result.Data
}
},
onError: (code, desc) =>
{
}
));Query local conversations by the conversation tag
For local conversations, you can call the LoadAllConversations method to obtain all local conversations and then perform conversation filtering yourself. The following is an example of querying all local conversations marked with EMConversation.EMMarkType.MARK_0:
// All final query results are put into result.
List result = new List();
List localConversations = SDKClient.Instance.ChatManager.LoadAllConversations();
foreach(var conv in localConversations)
{
List Marks = conv.Marks();
foreach(var mark in Marks)
{
if (MarkType.MarkType0 == mark)
{
result.Add(conv);
}
}
}Get all tags of a local conversation
You can call Conversation#Marks to get all the tags of a local conversation. The sample code is as follows:
Conversation conv = SDKClient.Instance.ChatManager.GetConversation("conversationId", conversationType);
List Marks = conv.Marks();Next steps
After implementing retrieving messages, you can refer to the following documents to add more messaging functionalities to your app:
