Bug: Service shows panic message when i send custom message by endpoint '/msg/send_msg'

[yfPanne]

What happened?

I tested sending custom messages, but it failed and caused an error on the server. I have already set the "content" field according to the prompt returned by the request, which needs to follow "CustomElem".
Service error message:

2023/08/01 10:29:07 [Recovery] 2023/08/01 - 10:29:07 panic recovered:
interface conversion: interface {} is nil, not string
/usr/local/go/src/runtime/iface.go:262 (0x40d689)
/Open-IM-Server/internal/api/msg.go:58 (0xf51228)
/Open-IM-Server/internal/api/msg.go:212 (0xf51ec5)
/go/pkg/mod/github.com/gin-gonic/[email protected]/context.go:174 (0xf4dc24)
/Open-IM-Server/pkg/common/mw/gin.go:107 (0xf4d8fc)
/go/pkg/mod/github.com/gin-gonic/[email protected]/context.go:174 (0xf4d3cd)
/Open-IM-Server/pkg/common/mw/gin.go:50 (0xf4d3b9)
/go/pkg/mod/github.com/gin-gonic/[email protected]/context.go:174 (0xf4d20d)
/Open-IM-Server/pkg/common/mw/gin.go:34 (0xf4d1f9)
/go/pkg/mod/github.com/gin-gonic/[email protected]/context.go:174 (0x97b281)
/go/pkg/mod/github.com/gin-gonic/[email protected]/recovery.go:102 (0x97b26c)
/go/pkg/mod/github.com/gin-gonic/[email protected]/context.go:174 (0x97a0b0)
/go/pkg/mod/github.com/gin-gonic/[email protected]/gin.go:620 (0x979d18)
/go/pkg/mod/github.com/gin-gonic/[email protected]/gin.go:576 (0x97985c)
/usr/local/go/src/net/http/server.go:2947 (0x6e7f0b)
/usr/local/go/src/net/http/server.go:1991 (0x6e3126)
/usr/local/go/src/runtime/asm_amd64.s:1594 (0x470420)

The information sent to /msg/send_msg through postman:

{
  "sendID": "1684367366441406464",
  "recvID": "1685906179542224896",
  "groupID": "",
  "senderNickname": "pan",
  "senderFaceURL": "http://www.pan.com",
  "senderPlatformID": 7,
  "content": {
    "data": "123",
    "extension": "a",
    "description": "v"
  },
  "contentType": 110,
  "sessionType": 1,
  "isOnlineOnly": false,
  "notOfflinePush": false,
  "offlinePushInfo": {
    "title": "send message",
    "desc": "",
    "ex": "",
    "iOSPushSound": "default",
    "iOSBadgeCount": true
  }
}

What did you expect to happen?

I hope the recipient can receive the customized message normally.

How can we reproduce it (as minimally and precisely as possible)?

Try to call endpoint /msg/send_msg and set contentType as 110.
Also should set content as the struct like:

  "content": {
    "data": "123",
    "extension": "a",
    "description": "v"
  }

Anything else we need to know?

I deploy it by docker-compose.
open-im-server image is openim/open_im_server:v3.0.1

version

$ {name} version
v3.0.1

Cloud provider

Tencent

OS version

# On Linux:
$ cat /etc/os-release
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
$ uname -a
Linux VM-4-16-debian 5.10.0-19-amd64 #1 SMP Debian 5.10.149-2 (2022-10-21) x86_64 GNU/Linux

Install tools

docker compose

[yfPanne]

@wangchuxiao-dev Is there anything helpful please?

[yfPanne]

This bug was fixed in version 3.2.