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-----Original Message-----
> From: Giulio Troccoli
> Sent: 08 December 2009 11:18
> To: us...@subversion.tigris.org; users@subversion.apache.org
> Subject: Authentication with Perl bindings
>
> I'm desperately trying to write something in Perl to authenticate.
>
> The functionality I want to reproduce is:
> - use the chached username and password if any
> - if not, ask for a password for the current username
> - if that fails, ask for a username and a password
>
> This is what the SVN client does, I think. But I'm not able
> to do it in Perl. I'm using the following code, which I found
> in the perldoc for SVN::Client
>
> use SVN::Client;
> my $ctx = new SVN::Client(
> auth => [
> SVN::Client::get_simple_provider(),
>
> SVN::Client::get_simple_prompt_provider(\&simple_prompt,2),
> SVN::Client::get_username_provider()
> ]
> );
>
> sub simple_prompt {
> my $cred = shift;
> my $realm = shift;
> my $default_username = shift;
> my $may_save = shift;
> my $pool = shift;
>
> print "Enter authentication info for realm: $realm\n";
> print "Username: ";
> my $username = <>;
> chomp($username);
> $cred->username($username);
> print "Password: ";
> my $password = <>;
> chomp($password);
> $cred->password($password);
> }
>
> (I know the password is in clear, but I can fix that later).
>
> If the username and password are cached this works perfectly
> well. When I comment out the get_simple_provider line (to
> simulate authentication data not being cached) I am asked for
> a username and password. If I enter the correct ones
> everything works. Otherwise I am asked two more times, and
> eventually the authentication fails.
>
> So, my questions are:
>
> 1) What is get_username_provider used for? When would I want
> to get the chached username only?
>
> 2) How can I implement my second point "ask for a password
> for the current username" ? I have tried changing
> simple_prompt as follows
>
> print "Enter authentication info for realm: $realm\n";
> # print "Username: ";
> my $username = $default_username;
> # chomp($username);
> $cred->username($username);
>
> And it works if I enter the correct password the first time.
> But if the password is wrong, not only I'm not asked again
> but I get a "Memory fault" error. I wasn't really expecting
> to be asked for the username but at least for the password
> for two more times.
>
> Anyone has done what I'm trying to do already? Anyone has any
> hints or suggestions?
>
> Thanks in advance
> Giulio
>
> P.S. I post this email to both mailing list @tigris and
> @apache, just becuase the apache one doesn't seem to be very active.
Well, after some experimentation I ahve found the solution, so I'm posting it
here for future reference.
The trick is to use two separate callback subroutines to
get_simple_prompt_provider: one to use the default username (and to not retry)
and one to ask for both username and password (with 1 retry, so a total of 3
attempts).
I have also used the IO::Prompt package to mask the password.
my $ctx = SVN::Client->new(
auth => [
SVN::Client::get_simple_provider(),
SVN::Client::get_simple_prompt_provider(\&ask_for_password,0),
SVN::Client::get_simple_prompt_provider(\&ask_for_username_and_password,1),
]
);
sub ask_for_password {
my ($cred, $realm, $default_username, $may_save, $pool) = @_;
print "Enter authentication info for realm: $realm\n";
$cred->username($default_username);
my $password = IO::Prompt::prompt('Password: ', -le => '*');
chomp($password);
$cred->password($password);
}
sub ask_for_username_and_password {
my ($cred, $realm, $default_username, $may_save, $pool) = @_;
print "Enter authentication info for realm: $realm\n";
print "Username: ";
my $username = <>;
chomp($username);
$cred->username($username);
my $password = IO::Prompt::prompt('Password: ', -le => '*');
chomp($password);
$cred->password($password);
}
