[fpc-devel] fphttpclient cannot download a file from w3.org

[Michael Van Canneyt]

I tested:

If I run a strace, it just hangs on the read operation:

connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("128.30.52.100")}, 16) = -1 EINPROGRESS (Operation now in progress)
select(4, NULL, [3], NULL, {tv_sec=3, tv_usec=0}) = 1 (out [3], left {tv_sec=2, tv_usec=884913})
getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
fcntl(3, F_GETFL)                       = 0x802 (flags O_RDWR|O_NONBLOCK)
fcntl(3, F_SETFL, O_RDWR)               = 0
sendto(3, "GET /TR/2002/REC-xmldsig-core-20"..., 112, 0, NULL, 0) = 112
recvfrom(3,

If I do the same with 'wget' it also hangs but in the end gets through..

But if you add some headers, you get a proper error response.

There is little I can do about that. I can only surmise Indy & wget send different
headers (E.G.user-agent) and the server reacts differently on that.



Michael.

On Mon, 1 Jul 2019, Ondrej Pokorny wrote:

> Hello,
>
> I cannot download 
> http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/xmldsig-core-schema.xsd 
> with TFPHTTPClient. Delphi INDY downloads it just fine. Does anybody 
> know what I am missing?
>
> Test code:
>
> program Project1;
> uses Classes, SysUtils, fphttpclient;
> procedure DownloadFile(const aURI: string; out outStream: TStream);
> var
>   xClient: TFPHTTPClient;
> begin
>   outStream := nil;
>   xClient := TFPHTTPClient.Create(nil);
>   try
>     xClient.AllowRedirect := True;
>     outStream := TMemoryStream.Create;
>     xClient.Get(aURI, outStream);
>     outStream.Position := 0;
>   except
>     on E: Exception do
>     begin
>       FreeAndNil(outStream);
>       Writeln(E.ClassName);
>       Writeln(E.Message);
>     end;
>   end;
>   xClient.Free;
> end;
> var
>   S: TStream;
> begin
> DownloadFile('http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/xmldsig-core-schema.xsd', 
> S);
>   S.Free;
>   Readln;
> end.
>
> Fails with exception:
>
> EHTTPClient
> Error reading data from socket
>
> #0 fpc_raiseexception(0x145fb14, 0x0, 0xffffffff) at ..\inc\except.inc:158
> #1 FILLBUFFER(0x145fb14) at fcl-web\src\base\fphttpclient.pp:731
> #2 READSTRING(0x15e1c30, 0x0) at fcl-web\src\base\fphttpclient.pp:749
> #3 READRESPONSEHEADERS(0x15e1c30) at fcl-web\src\base\fphttpclient.pp:854
> #4 READRESPONSE(0x15e1c30, 0x15b5dc0, 0x145fdb8, 0, false) at 
> fcl-web\src\base\fphttpclient.pp:1132
> #5 DONORMALREQUEST(0x15e1c30, {PROTOCOL = 0x15b5e4c 'http', USERNAME = 
> 0x0, PASSWORD = 0x0, HOST = 0x15b5ecc 'www.w3.org', PORT = 0, PATH = 
> 0x1601c9c '/TR/2002/REC-xmldsig-core'..., DOCUMENT = 0x15bc58c 
> 'xmldsig-core-schema.xsd', PARAMS = 0x0, BOOKMARK = 0x0, HASAUTHORITY = 
> true}, 0x449d58 'GET', 0x15b5dc0, 0x145fdb8, 0, false, false) at 
> fcl-web\src\base\fphttpclient.pp:1226
> #6 DOMETHOD(0x15e1c30, 0x449d58 'GET', 0x443060 
> 'http://www.w3.org/TR/2002'..., 0x15b5dc0, 0x145fdb8, 0) at 
> fcl-web\src\base\fphttpclient.pp:1283
> #7 HTTPMETHOD(0x15e1c30, 0x449d58 'GET', 0x443060 
> 'http://www.w3.org/TR/2002'..., 0x15b5dc0, 0x145fdb8, 0) at 
> fcl-web\src\base\fphttpclient.pp:1397
> #8 GET(0x15e1c30, 0x443060 'http://www.w3.org/TR/2002'..., 0x15b5dc0) at 
> fcl-web\src\base\fphttpclient.pp:1439
> #9 DOWNLOADFILE(0x443060 'http://www.w3.org/TR/2002'..., 0x15b5dc0) at 
> project1.lpr:14
> #10 main at project1.lpr:30
>
> Ondrej
>
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