request help: response_rewrite plugin can not return result

[zhangweidongyyl]

Issue description

when i write plugin like response_rewrite ,curl can not return result, but the log is all right,this is why。response_rewrite plugin can right exec
`

do

function _M.body_filter(conf, ctx)

local function push_data(premature, uri,args,result)
    if premature then
        return
    end
    local httpc, err = http:new()
    if err then
        result = "fail create http conn"
    end
    httpc:set_timeout(time)
    httpc:set_timeout(connect_timeout,
            send_timeout, read_timeout)
    local url = "http://" .. host_str ..":" .. host_port
    local res, err = httpc:request_uri(url,{path = uri,query = args})
    if not res then
        result = "fail to request"
        core.log.error("failed to request : ", err)
        return
    end
    result = result .. res.body
    core.log.info("res.body：",res.body)                                               -- 输出响应体
    core.log.info("result:", result)
end
local ok, err = ngx.timer.at(0, push_data,ngx.var.uri, ngx.var.args,result)
if err then
    ngx.log(ngx.ERR, "failed to create timer: ", err)
    return
end
if not ok then
    ngx.log(ngx.ERR, "failed to create timer: ", err)
    return
end
ngx.arg[1] = result
ngx.arg[2] = true

end
end
`

Environment

• apisix version (cmd: apisix version):
• OS (cmd: uname -a):
• OpenResty / Nginx version (cmd: nginx -V or openresty -V):
• etcd version, if have (cmd: run curl http://127.0.0.1:9090/v1/server_info to get the info from server-info API):
• apisix-dashboard version, if have:
• the plugin runner version, if the issue is about a plugin runner (cmd: depended on the kind of runner):
• luarocks version, if the issue is about installation (cmd: luarocks --version):

Steps to reproduce

do plugin like this

Actual result

can right return res

Error log

no err log

Expected result

No response

[zhangweidongyyl]

plugin log is right ,but curl return

curl: (52) Empty reply from server

[tzssangglass]

We do not check the code written by the user himself. If the issue is not relevant to the project, I will turn it into a discussion.