Custom HTTP header in client request

jaclas · 2017-07-14 09:45:10

How to add custom HTTP header to client request?

Last edited by jaclas (2017-07-14 09:45:38)

jaclas · 2017-07-21 08:38:09

Any suggestion?
Do I have to override this method:

function TSQLHttpClientRequest.InternalRequest(const url, method: RawUTF8; var Header, Data, DataType: RawUTF8): Int64Rec;

?

ab · 2017-07-21 12:11:31

Why do you need to mess the HTTP headers?

Do you expect this with interface-based services or method-based services?

jaclas · 2017-07-21 13:12:03

I work with interface-based service.
I want add some header for debug purpose. In header because I can add in one place to debug in all services at once.

ab · 2017-07-21 13:37:37

There is no simple way of doing this on the client side... unless you override the low-level HTTP classes...

jaclas · 2017-07-22 07:09:37

I did this:

type
  TMySQLHttpClientRequest = class(TSQLHttpClientWinHTTP)
  protected
    function InternalRequest(const url, method: RawUTF8; var Header, Data, DataType: RawUTF8): Int64Rec; override;
  end;


implementation

function TMySQLHttpClientRequest.InternalRequest(const url, method: RawUTF8; var Header, Data, DataType: RawUTF8): Int64Rec;
begin
  Header := 'myheader: somedata';
  Result := inherited InternalRequest(url, method, Header, Data, DataType);
end;

And it works :-)

Are there any hidden side effects here?

ab · 2017-07-22 16:12:27

If the caller set a header, it won't work.
You should test for any existing header.

jaclas · 2017-07-25 13:23:29

You mean should I do something like this:

 if Header <> '' then
 begin
  Header := Header + #13#10 + 'myheader: somedata';
 end;

?

ab · 2017-07-25 16:32:32

Or more correctly:

if Header <> '' then
  Header := Header + #13#10;
Header := Header + 'myheader: somedata';

Or even:

Header := AddToCSV('myheader: somedata', Header, #13#10);

jaclas · 2017-07-25 18:47:17

Thanks for tip with AddToCSV!

But I have one question.

This code:

if Header <> '' then
  Header := Header + #13#10;
Header := Header + 'myheader: somedata';

is better than:

if Header <> '' then
 begin
  Header := Header + #13#10 + 'myheader: somedata';
 end;

...because? You mean better memory management? Less allocations? Or...?

ab · 2017-07-25 19:39:14

The 2nd do not append 'myheader: somedata' to Header.

jaclas · 2017-07-25 20:37:38

Oops... My total disgrace! Sorry :-)

mORMot Open Source

#1 2017-07-14 09:45:10

Custom HTTP header in client request

#2 2017-07-21 08:38:09

Re: Custom HTTP header in client request

#3 2017-07-21 12:11:31

Re: Custom HTTP header in client request

#4 2017-07-21 13:12:03

Re: Custom HTTP header in client request

#5 2017-07-21 13:37:37

Re: Custom HTTP header in client request

#6 2017-07-22 07:09:37

Re: Custom HTTP header in client request

#7 2017-07-22 16:12:27

Re: Custom HTTP header in client request

#8 2017-07-25 13:23:29

Re: Custom HTTP header in client request

#9 2017-07-25 16:32:32

Re: Custom HTTP header in client request

#10 2017-07-25 18:47:17

Re: Custom HTTP header in client request

#11 2017-07-25 19:39:14

Re: Custom HTTP header in client request

#12 2017-07-25 20:37:38

Re: Custom HTTP header in client request

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