[fpc-pascal] fcl-web: Trequest.RemoteAddr is empty (sometimes)

[Santiago A.]

El 08/01/2021 a las 10:16, Luca Olivetti via fpc-pascal escribió:
> El 7/1/21 a les 16:59, Luca Olivetti via fpc-pascal ha escrit:
>> El 7/1/21 a les 16:15, Luca Olivetti via fpc-pascal ha escrit:
>>> Hello,
>>>
>>> I need to tailor the content based on the remote ip address.
>>> I use the property RemoteAddr of a TRequest, but sometimes it is empty.
>>> I see that it is a header, what I didn't see (yet, I'll trace 
>>> through the code later) is if it is sent from the remote host or is 
>>> it filled based on the ip address of the connection.
>>> If the former, is there a more reliable way to obtain the connected 
>>> ip address?
>>> If the latter is it a bug?
>>
>> I now see that it set in TFPHTTPConnection.ReadRequestHeaders:
>>
>>     Result.RemoteAddress := SocketAddrToString(FSocket.RemoteAddress)
>>
>> In turn SocketAddrToString returns an empty string if the address is 
>> ipv6, but in my case it shouldn't be (the clients, firefox under 
>> windows 10 uses the ipv4 address of the server and most of the time I 
>> get the correct remote address, even from the same client).
>
> Besides, it seems that the server only listens on ipv4.
> I'm puzzled, I really can't see where this empty RemoteAddress could 
> come from.
>
> Bye
In windows 10 when you connect to localhost, it may connect with IPV6 
and route to ipv4 with weird results.
Try to connect using IP 127.0.0.1 http://127.0.0.1
You may also add in C:\Windows\System32\drivers\etc\hosts a line like
localhost4 127.0.0.1
and then http://localhost4
You may also disable IPV6 service if you don't use it. I have, because 
it is seldom used, it looks like every device/system still works only 
with IPV4

-- 
Saludos

Santiago A.