Http request sent an empty body
According to post function document https://pub.dev/documentation/http/latest/http/post.html
If body is String , the content-type of the request will default to "text/plain".
If body is Map , the content-type of the request will default to "application/x-www-form-urlencoded".
You can set header to application/json
code snippet
http.post(url, headers: {"Content-Type": "application/json"}, body: body