I'm writing a program to perform checks on websites to test they're current status, e.g. 200 OK. I'm using Indy HTTP shipped with Delphi 2010 for this task and have the current code.
procedure TCheckSiteIndividual.Execute;
var
http : TIdhttp;
begin
try
try
http := Tidhttp.create(nil); //Create indy
http.Get(CSiteURL,nil); //Send Request To Check Site
except
on E: EIdHTTPProtocolException do
status := http.ResponseText; // or: code := E.ErrorCode;
end;
status := http.ResponseText; //Return Status of Site
synchronize(updateform); //Update data to form
finally
http.Free;
end;
end;
The CSiteURL variable is set in the Thread Constructor, and the status variable is a variable to the entire thread.
The try, except parts of this code came from Remy Lebeau - TeamB here which was a question I asked when initially fiddling around with this idea. The problem I'm having is that this code only works if the site returns a 200 OK code. Anything else causes an exception, including if I disable the internet. This also causes exceptions on sites that redirect e.g. www.google.com causes an exception during debugging I presume causes it's redirecting to www.google.co.uk for me, however if I continue past the exception then it returns a 301 FOUND code with no problems.
The final result I'm looking for it for it to give me a return based on whether the site is online or having error (e.g. HTML RETURN CODE) additionally giving feedback when the site doesn't exist (e.g. a non-registered URL) or just can't be contacted.
The other peices of advice I'm looking for are into how to get some more information back from the request. Specifically at the moment I'm looking to also get the IP of the site that was checked.
It would also be nice to have it work without needing to have http:// before any URL, so for example www.google.com will work which at the moment it doesn't because of unknown protocol.
Basically it would be great if someone had a link to some nice documentation for IndyHTTP because it seems to be sparse,
Answer
Yes, of course it causes an exception. That's how Indy works, and that's why Remy advised you to catch exceptions.
What you're confused by now is that even though you have code to catch exceptions, the Delphi debugger still intercepts them and pauses execution of your program to notify you that an exception occurred. I've written about that phenomenon before.
Since you're apparently not interested in knowing about non-status-200 exceptions while you're debugging — because your program is designed to handle all those errors itself — your best option is probably to add EIdHTTPProtocolException to the debugger's list of ignored exceptions. The easiest way to do that is to choose "Ignore this exception type" the next time the debugger notifies you.