Addons that Require Licenses

If your script requires a commercial license, you have 3 options:

1. Handle the license requirements and entry from the installed addon.
2. Use the $meta_info key "vendor_license" to install regardless of whether a valid license was entered (ie, your addon script will just detect an invalid license and handle as you wish).
3. Use the $meta_info key "vendor_license" to install only if the license entered was valid.

The first step is to create an 'install_field' key called 'vendor_license', as well as a simple check in 'install_field_hook'.

After that:

To simply allow them to enter a ^\w+$ license key and put it in [% vendor_license %]:

'vendor_license' => {}, 

To allow them to enter a license key of any format you wish and put it in [% vendor_license %]:

'vendor_license' => {
    'string_is_ok' => sub {
        my($lisc_string) = @_; # 32 digits
        return 1 if length $lisc_string == 32 && $lisc_string =~ m/^\d+$/; # ^\d{32}$
        return 0;
    },
},

The following will allow the customer to enter anything into the field and have a script verify the license key is valid or else not install/upgrade it:

'vendor_license' => {
    'verify_url'      => 'http://foo.bar.baz/lisc.pl',
    #?lisc=license_string_from_input_here
    'url_says_its_ok' => sub {
        my ($url_result) = @_; # it is empty if url failed
        return 1 if $url_result =~ m/Vendor says Valid/;
        return 0;
    },
},