Continuing from my previous discussion about connecting to LinkedIn - see Injecting a value into HTTP::Header

I have managed to authenticate with LinkedIn using LWP::Authen::OAuth2::ServiceProvider::LinkedIn which I am writing. This is used by LWP::Authen::OAuth2. LinkedIn doesn't obey the OAuth2 standard which is why there was a need to add extra information.

But now I am having difficulty posting anything to LinkedIn and I am getting an error from LWP::Authen::OAuth2
Can't call method "request" on an undefined value at /home/shoples1/perl5/lib/perl5/LWP/Authen/OAuth2.pm line 107.

I've looked at the source code of LWP::Authen::OAuth2 to try and see what I need to do differently to make this work. However, I cannot fathom how that module is supposed to work. Clearly, it does work and it is my understanding that is missing because it is a working module. But these two subroutines just seem to be calling each other: 

sub request {
    my ($self, $request, @rest) = @_;
    return $self->access_token->request($self, $request, @rest); # <- 
+line 107
}

sub access_token {
    my $self = shift;
 
    return $self->{access_token};
}

[download]
Having gone through the authentication and obtained a token, I am trying to make a post using the following code. I am not expecting it to actually make a post yet but I was expecting to get an error from LinkedIn and not an error from Perl. 
my $params = {
    'content'    => {
        'title'       => 'Test Title',
        'descrition'  => 'Test message',
    },
};
my $res = $linkedin->post('https://api.linkedin.com/v2/shares', $param
+s);
if ($res) {
    print "Content-type: text/plain\n\n";
    print $res;
    exit 0;
}

[download]
Can you help me understand what the two subroutines in LWP::Authen::OAuth2 are actually doing?

In reply to Subs calling themselves by Bod

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