# NAME

Plack::Middleware::EmulateOPTIONS - handle OPTIONS requests as HEAD

# VERSION

version v0.3.2

# SYNOPSIS

```perl
use Plack::Builder;

builder {

  enable "EmulateOPTIONS",
    filter => sub {
        my $env = shift;
        return $env->{PATH_INFO} =~ m[^/static/];
      };

  ...

};
```

# DESCRIPTION

This middleware adds support for handling HTTP `OPTIONS` requests, by internally rewriting them as `HEAD` requests.

If the requests succeed, then it will add `Allow` headers using the ["callback"](#callback) method.

If the requests do not succeed, then the responses are passed unchanged.

You can add the ["filter"](#filter) attribute to determine whether it will proxy `HEAD` requests.

# ATTRIBUTES

## filter

This is an optional code reference for a function that takes the [PSGI](https://metacpan.org/pod/PSGI) environment and returns true or false as to
whether the request should be proxied.

For instance, if you have CORS handler for a specific path, you might return false for those requests. Alternatively,
you might use the ["callback"](#callback).

If you need a different value for the `Allow` headers, then you should handle the requests separately.

## callback

This is an optional code reference that modifies the response headers.

By default, it sets the `Allow` header to "GET, HEAD, OPTIONS".

If you override this, then you will need to manually set the header yourself, for example:

```perl
use Plack::Util;

enable "EmulateOPTIONS",
  callback => sub {
      my $res = shift;
      my $env = shift;

      my @allowed = qw( GET HEAD OPTIONS );
      if ( $env->{PATH_INFO} =~ m[^/api/] ) {
         push @allowed, qw( POST PUT DELETE );
      }

      Plack::Util::header_set( $res->[1], 'allow', join(", ", @allowed) );

    };
```

This was added in v0.2.0.

# SUPPORT FOR OLDER PERL VERSIONS

Since v0.3.0, the this module requires Perl v5.14 or later.

If you need this module on Perl v5.10, please use one of the v0.2.x
versions of this module.  Significant bug or security fixes may be
backported to those versions.

# SOURCE

The development version is on github at [https://github.com/robrwo/Plack-Middleware-EmulateOPTIONS](https://github.com/robrwo/Plack-Middleware-EmulateOPTIONS)
and may be cloned from [git://github.com/robrwo/Plack-Middleware-EmulateOPTIONS.git](git://github.com/robrwo/Plack-Middleware-EmulateOPTIONS.git)

# BUGS

Please report any bugs or feature requests on the bugtracker website
[https://github.com/robrwo/Plack-Middleware-EmulateOPTIONS/issues](https://github.com/robrwo/Plack-Middleware-EmulateOPTIONS/issues)

When submitting a bug or request, please include a test-file or a
patch to an existing test-file that illustrates the bug or desired
feature.

# AUTHOR

Robert Rothenberg <rrwo@cpan.org>

# COPYRIGHT AND LICENSE

This software is Copyright (c) 2022-2023 by Robert Rothenberg.

This is free software, licensed under:

```
The Artistic License 2.0 (GPL Compatible)
```