Re: [pgadmin-hackers] [pgAdmin4][runtime][patch]: RM#2398 - Proxy notbypassed for embedded server in runtime on Windows

Good catch - thanks Neel. I don't have my main dev laptop with me, so
I'll have to test this next week. Watch this space :-)

On Wed, May 24, 2017 at 4:22 AM, Neel Patel <neel.patel@enterprisedb.com> wrote:
> Hi,
>
> After debugging the issue in windows, we came to know that "random port"
> generation logic in runtime is getting failed if we configured proxy server
> in windows.
>
> Below are the code where we are finding random free port and use with our
> URL "localhost:<port>". Below code return "0" as port value so application
> is not able to start and it hangs on splash screen. Here, if we configured
> proxy server in windows then "bind" method always return false and gives
> message "Operation not permitted" but when we disable proxy server then
> below code gives valid random port number.
>
> QTcpSocket socket;
> socket.bind(0, QTcpSocket::ShareAddress);
> port = socket.localPort();
>
> Same happens with Linux OS - when user defined "http_proxy" environment
> variable and run pgAdmin4 application then above code fails and gives "0" as
> random port number and application hangs on splash screen.
>
>
> From the below Qt 5.8 released link, we came to know that "random port"
> generation work well after setting application level proxy.
> http://blog.qt.io/blog/2017/01/23/qt-5-8-released/
>
> QNetworkProxy::setApplicationProxy(QNetworkProxy());
>
> After setting above, "bind" method return true and gives correct port number
> and application starts working. We are also setting
> "setUseSystemConfiguration=true" after setting application level proxy which
> will override the setting and use platform specific system proxy
> configuration.
>
> From the below link, it looks like fixed in Qt 5.9.
> https://bugreports.qt.io/browse/QTBUG-58374
> https://codereview.qt-project.org/#/c/186124/
>
> I have tested with Qt 5.8 Web Engine and webkit in windows. Do review it and
> let me know for comments.
>
> Thanks,
> Neel Patel
>
> On Fri, May 19, 2017 at 4:37 PM, Dave Page <dpage@pgadmin.org> wrote:
>>
>> On Thu, May 18, 2017 at 3:42 PM, Neel Patel <neel.patel@enterprisedb.com>
>> wrote:
>> > Hi Dave,
>> >
>> > Please find attached patch for the fix of RM#2398 - "Proxy not bypassed
>> > for
>> > embedded server in runtime on Windows".
>> >
>> > Observation:-
>> > We have observed this issue only with Qt WebEngine. We have not observed
>> > this issue with Webkit ( Tested with Qt 5.3 ).
>> >
>> > Issue:-
>> > If user set option "Bypass proxy server for local addresses" then
>> > WebEngine
>> > doesn't bypass the request for local addresses even if that option is
>> > set.
>> >
>> > Solution:-
>> > Now if user set option "Bypass proxy server for local addresses" then
>> > Web
>> > Engine bypass the request for localhost and if user unset then request
>> > will
>> > not be bypassed.
>> >
>> > Please find attached fix for this issue. Do review and test it and let
>> > me
>> > know for any issue.
>>
>> Noted on the ticket:
>>
>> ====
>> Right, but as Maxim has noted, the proxy code is there to allow users
>> to browse to online docs, so it can't just be disabled.
>>
>> This likely worked in 1.3 as that used QtWebEngine (which had a bunch
>> of other issues). We need to fix it for QtWebKit, so that it honors
>> the bypass proxy for local addresses option.
>> ====
>>
>>
>> --
>> Dave Page
>> Blog: http://pgsnake.blogspot.com
>> Twitter: @pgsnake
>>
>> EnterpriseDB UK: http://www.enterprisedb.com
>> The Enterprise PostgreSQL Company
>
>



--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

EnterpriseDB UK: http://www.enterprisedb.com
The Enterprise PostgreSQL Company