Platform API

Send a message

Use this endpoint to send one message from a business backend as a selected user or system account. It is intended for system messages, operational notifications, agent-assisted sending, and historical message migration. Normal user chat should generally be sent by the client SDK under the signed-in user's identity.

HTTP request

POST {API_ADDRESS}/msg/send_msg

Request example

curl --request POST "${API_ADDRESS}/msg/send_msg" \
  --header "Content-Type: application/json; charset=utf-8" \
  --header "operationID: ${OPERATION_ID}" \
  --header "token: ${ADMIN_TOKEN}" \
  --data-raw '{
  "sendID": "openIMAdmin",
  "recvID": "user_001",
  "groupID": "",
  "senderNickname": "System",
  "senderFaceURL": "https://example.com/system.png",
  "senderPlatformID": 10,
  "content": {"content": "hello"},
  "contentType": 101,
  "sessionType": 1,
  "isOnlineOnly": false,
  "notOfflinePush": false,
  "sendTime": 1719800000000,
  "offlinePushInfo": {
    "title": "OpenIM message",
    "desc": "You have a new message",
    "ex": "",
    "iOSPushSound": "default",
    "iOSBadgeCount": true,
    "signalInfo": ""
  },
  "ex": ""
}'

Request body

Parameter	Required	Type	Description
sendID	Yes	string	Sender user ID, including a system notification account or ordinary user.
recvID	One-to-one	string	Recipient user ID when `sessionType` is `1`.
groupID	Group	string	Target group ID when `sessionType` is `3`.
senderNickname	No	string	Sender nickname.
senderFaceURL	No	string	Sender avatar URL.
senderPlatformID	No	int	Sender platform. Administrative sending normally uses `10`; see `PlatformID`.
content	Yes	object	Message payload determined by `contentType`. See Message content types.
contentType	Yes	int	Message content type.
sessionType	Yes	int	Conversation type. See `ConversationType`.
isOnlineOnly	No	boolean	When `true`, deliver online only and disable history, persistence, sender synchronization, and conversation updates.
notOfflinePush	No	boolean	When `true`, do not trigger offline push.
sendTime	No	int	Send time as a Unix timestamp in milliseconds. Use it to preserve time during migration.
offlinePushInfo	No	object	Offline push title, description, extension data, iOS sound and badge behavior, and signaling data.
ex	No	string	Message extension data.

For one-to-one chat, use sessionType: 1 with recvID. For group chat, use sessionType: 3 with groupID.

Response

{
  "errCode": 0,
  "errMsg": "",
  "errDlt": "",
  "data": {
    "serverMsgID": "server_msg_001",
    "clientMsgID": "client_msg_001",
    "sendTime": 1719800000000,
    "modify": null
  }
}

Field	Type	Description
data.serverMsgID	string	Server message ID.
data.clientMsgID	string	Client message ID.
data.sendTime	int	Effective send time in Unix milliseconds.
data.modify	object	Message data modified by a Webhook or server rule; may be `null`.

For migration, write messages in conversation order, preserve the original sendTime, and retain a source message ID in extension data for idempotency. Import users, groups, and relationships before messages.

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HTTP request

Request example

Request body

Response

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