# Differences in requests after access to the gateway

1. After accessing the gateway, the request to access the rear source station is no longer the user terminal IP on the IP, but the gateway's exit node IP.

A. If you need to configure the IP frequency limiting policy, be sure to add the gateway exit node to the white list

B. If you need to get the user's actual IP, you can use the following header: xwx-client-ip, xforwarded-for, x-real-ip

2.After accessing the gateway, the requested UA and Referer may not meet expectations, please avoid using the UA and Referer to determine whether it is Weixin Mini Program access

A. The Referer requested by the gateway may not be able to identify the version of Weixin Mini Program (i.e. the Mini Program version may be 0)

B. The User-Agent requested by the gateway may be the default UA: Mozilla / 4.0

3. After accessing the gateway, all headers of the request are changed to lowercase by default

A. If a cookie: xxx = yyy, the header received by the background will become cookie: xxx = yyy

4. After accessing the gateway, all headers beginning with x - wx- will be discarded

A. Such as x-wx-my-custom-header, these headers will be discarded in the gateway layer, the background can not receive

5.After accessing the gateway, if there is a complex query in URL, its behavior may differ from wx.request

A. If the Chinese query is not urlencode:?Chinese = 123, whose parameters are converted with encodeURIComponent

6.After accessing the gateway, the Weixin Mini Program request may behave differently from wx.request if it is not labeled dataType

A. If the back packet is binary, Weixin Mini Program may receive a UTF-8 character string or enter a fail callback.To use binary backpacks, be sure to use the dataType: "arraybuffer" when requesting

7. After accessing the gateway, res.errMsg will change to "gateway.call: ok" instead of "request: ok"