Send a message in a chat room. Message types include text, image, audio, video, location, files, alert, and custom messages.

Flow control in chat rooms

The flow control mechanism in chat rooms may drop some messages when participants send a large number of messages in a chat room.

To ensure user experience (such as avoiding server overload), the following flow control mechanism is applied:

• For normal messages, users in chat room can receive up to 20 messages per second, and the excessive messages will be randomly dropped. To avoid losing important messages (server-side messages), you can set the HighPriority parameter to true to receive server-side messages with high priority and important messages will not be lost.
• For high-priority messages, at most 10 messages are received per seconds. The excessive messages may be dropped.

Overview

Users can send messages in chat rooms, such as text messages, picture messages, voice messages, and location messages.

This API can send or resend messages by setting resendFlag. For details, see the description of this parameter in Request Parameters below.

API rate limit

• Apps can call the API by 100 times per second. If API calls exceeds the rate limit, requests from the app will be blocked for 10 seconds before the API become available again.

Request URI

httpPOST https://api.netease.im/nimserver/chatroom/sendMsg.action HTTP/1.1
Content-Type:application/x-www-form-urlencoded;charset=utf-8

Request parameters

• For information about how to set the header in a POST request, see API Call methods.

• The settings of the body in a POST request:

Parameter	Type	Required	Description
roomid	Long	Yes	Chat room ID
msgId	String	Yes	message ID, using random strings such as uuid, messages with the same msgId will be deduplicated by the client.< /td>
attach	String	No	Message body as the body field in message format example, up to 4,069 characters long.
fromAccid	String	Yes	user account sending the message, accid
ignoreMute	Boolean	No	Whether to ignore the temporary mute of members, true: ignore; false: do not ignore, the default is false.< /td>
msgType	Integer	Yes	Message type: 0: Text message, 1: Image message, 2: Audio message, 3: Video message, 4: Location message, 6: File message, 10: Alert, 100: Custom messageFor applications that are not integrated to GuardEase moderation service, custom messages will not be forwarded to the moderation service for review
subType	Integer	No	Custom message subtype, a value greater than 0.
resendFlag	Integer	No	Flag for resending a message 0: Non-resent message, 1: Resent message. If users resend a message, the deduplication logic will be applied based on `msgId`.
ext	String	No	extension field for messages, JSON, up to 4,096 characters long.
route	Integer	No	Whether the message is synced using webhooks 0: No; 1: Yes (default)< /td>
skipHistory	Integer	No	Whether to store message history in the cloud 0: Yes (default); 1: No
abandonRatio	Integer	No	The probability for dropping a message, value range [0-9999]; 0: does not drop the message (default), 9999: 99.99% probability of dropping the message This parameter can be used to flow control messages for specific businessIf this parameter is specified, the following highPriority parameters becomes invalid /note>
highPriority	Boolean	No	true: high-priority message. High-priority messages are delivered first; false: low-priority message (default) High-priority messages can be set to be resent. For details, see the `needHighPriorityMsgResend` parameterUse this parameter to ensure high-priority messages are delivered first. If you set all messages to high priority, the setting has no effect. A single chat room can handle up to 10 high-priority messages per second, and any excessive messages will be processed as normal messages by default.
needHighPriorityMsgResend	Boolean	No	true: the message will be resent (default), false: the message will not be resent. If you set the value to true, a user will still receive this message during the validity period when the user leaves and rejoins the chat room. The current validity period last 30s by default. If the highPriority value is not specified, `needHighPriorityMsgResend` does not take effect
useYidun	Integer	No	Whether a message (including custom messages) uses GuardEase moderation service. Set the value to 0. Any other value indicates that the value is unspecified. 0: indicates that the message is not audited by the GuardEase moderation service when the moderation service is activated. If you do not specify this field, the message will be forwarded to GuardEase moderation service for review by default when the service is activated.
yidunAntiCheating	String	No	The parameter for anti-cheating detection transferred in pass-through mode to GuardEase, JSON, with a maximum length of 1024 characters, (For details, please see GuardEase anti-spam exclusive field)
yidunAntiSpamExt	String	No	The parameter for anti-spam enhanced transferred in pass-through mode to GuardEase, JSON, with a maximum length of 1024 characters, (for details, see GuardEase moderation service custom extension field)
bid	String	No	Custom business ID of GuardEase moderation service. Custom moderation allows you to review the content of a single message in addition to the default moderation service. To configure custom moderation rules, contact our technical support using WhatsApp or online support for help.
antispam	Boolean	No	For applications that have activated GuardEase moderation service, whether the message are reviewed by GuardEase (antispamCustom), default value:false Only valid for custom messages (message type: 100)
notifyTargetTags	String	No	Target tag expression, used to set the delivery targets in the chat room messages, the maximum length is 128 characters. For more information about how to use tags and examples, see Tag expression
antispamCustom	String	No	Custom moderation rules. Valid when the `antispam` parameter is set to `true`, JSON, length limit is the same as the body field. The maximum length is 5000 characters, the required antispamCustom format is as follows: {"type":1,"data":"custom content"} Field description: 1. type: 1: text; 2: image; 3: video 2. data: Text or image URL
env	String	No	The environment name specified in the CommsEase console sync webhooks as shown in the figure below. A maximum of 32 characters are allowed.
chatMsgPriority	Integer	No	The priority of messages sent through the CDN channel, optional values: 0 (default), 1, 2, 3
forbiddenIfHighPriorityMsgFreq	Integer	No	If high-priority messages are degraded as normal messages, return 403 error code 0: downgrade to normal message (default), 1: return 403 error code
locX	Double	No	Spatial coordinate X, used to send spatial messages within a specified range in scenarios. Client SDK v8.11.0 and later support.
locY	Double	No	Spatial coordinate Y, used to send spatial messages within a specified range. Client SDK v8.11.0 and later support.
locZ	Double	No	Spatial coordinate Z, used to send spatial messages within a specified range. Client SDK v8.11.0 and later support.

Response fields

Parameter	Type	Description
code	Integer	Response status code
desc	String	Detailed description of the sent message.

desc representation

Parameter	Type	Description
time	Long	Timestamp of a sent message in milliseconds.
fromAvator	String	Avatar of the message sender.
msgid_client	Long	Client message ID
fromClientType	String	Type of the client sending a message.
roomId	Long	Chat room ID
fromAccount	String	User account sending a message. accid
fromNick	String	Nickname of the sender.
attach	String	Message body
type	Integer	Message type
ext	String	Extension field
highPriorityFlag	Integer	High priority message flag. Normal messages have no such flag.
msgAbandonFlag	Integer	The message drop flag. This flag will be returned only when the abandonRatio parameter is passed. If this flag is not returned, a message is not dropped.

Example

Example request (cURL)

curlcurl -X POST -H "CheckSum: 51eb13ea***1c65c7866c366" -H "AppKey: f541664***6ad7799" -H "Nonce: 1" -H "CurTime: 1451207708" -H "Content-Type: application/x-www-form-urlencoded" -d 'roomid=36&fromAccid=zhangsan&msgType=0&attach=This+is+test+msg&msgId=c9e6c306-804f-4ec3-b8f0-573778829419' 'https://api.netease.im/nimserver/chatroom/sendMsg.action'

Example success response

json"Content-Type": "application/json; charset=utf-8"
{
"code":200,
"desc":{
  "time": "1456396333115",
  "fromAvator":"http://b12026.nos.netease.com/MTAxMTAxMA==/bmltYV84NDU4OF8xNDU1ODczMjA2NzUwX2QzNjkxMjI2LWY2NmQtNDQ3Ni0E2LTg4NGE4MDNmOGIwMQ==",
  "msgid_client": "c9e6c306-804f-4ec3-b8f0-573778829419",
  "fromClientType": "REST",
  "attach": "This+is+test+msg",
  "roomId": "36",
  "fromAccount": "zhangsan",
  "fromNick": "Zhangsan",
  "type": "0",
  "ext": "",
  "highPriorityFlag":1, //High priority message flag, a normal message does not have such flag. 
  "msgAbandonFlag":"1" //The dropped message flag. This flag will be returned only when the abandonRatio parameter is passed. If this flag is not returned, the message has not been discarded.
}
}

Example error response

json"Content-Type": "application/json; charset=utf-8"
{
    "code":414
    "desc":"msgContents size exceeded" //Message body exceeded the size limit.
}

Status codes

The following status codes are related to responses of this API. For the complete error codes, see Status codes.

Code	Description	Recommendation
200	Success	-
414	Parameter error	Check the format and restrictions of arguments based on the error message
403	Illegal operation	Exceptions, such as invalid chat room name, hit moderation rules or without the chat room permission.
416	API call rate limit. Too many requests within a short period of time	Lower the number of requests
419	Limit of chat rooms exceeded.	-
500	Internal Server Error	-
13009	The scheduled closing of chat rooms is disabled	Enable the scheduled closing function for chat rooms in the CommsEase console.