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Plack::Middleware::Auth::Basic - Simple basic authentication middleware


  use Plack::Builder;
  my $app = sub { ... };

  builder {
      enable "Auth::Basic", authenticator => \&authen_cb;

  sub authen_cb {
      my($username, $password, $env) = @_;
      return $username eq 'admin' && $password eq 's3cr3t';


Plack::Middleware::Auth::Basic is a basic authentication handler for Plack.



A callback function that takes username, password and PSGI environment supplied and returns whether the authentication succeeds. Required.

Authenticator can also be an object that responds to authenticate method that takes username and password and returns boolean, so backends for Authen::Simple is perfect to use:

  use Authen::Simple::LDAP;
  enable "Auth::Basic", authenticator => Authen::Simple::LDAP->new(...);

Realm name to display in the basic authentication dialog. Defaults to restricted area.


This middleware expects that the application has a full access to the headers sent by clients in PSGI environment. That is normally the case with standalone Perl PSGI web servers such as Starman or HTTP::Server::Simple::PSGI.

However, in a web server configuration where you can't achieve this (i.e. using your application via Apache's mod_cgi), this middleware does not work since your application can't know the value of Authorization: header.

If you use Apache as a web server and CGI to run your PSGI application, you can either a) compile Apache with -DSECURITY_HOLE_PASS_AUTHORIZATION option, or b) use mod_rewrite to pass the Authorization header to the application with the rewrite rule like following.

  RewriteEngine on
  RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization},L]


Tatsuhiko Miyagawa