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NAME

Catalyst::Plugin::Session::Store::Cookie - Store session data in the cookie

SYNOPSIS

    package MyApp;

    use Catalyst qw/
      Session
      Session::State::Cookie
      Session::Store::Cookie
    /;

    __PACKAGE__->config(
      'Plugin::Session' => {
        storage_cookie_name => ...,
        storage_cookie_expires => ...,
        storage_secret_key => ...,
        storage_cookie_secure => ...,
        storage_cookie_httponly => ...,
        storage_cookie_samesite => ...,
      },
      ## More configuration
    );

    __PACKAGE__->setup;

DESCRIPTION

What's old is new again...

Store session data in the client cookie, like in 1995. Handy when you don't want to setup yet another storage system just for supporting sessions and authentication. Can be very fast since you avoid the overhead of requesting and deserializing session information from whatever you are using to store it. Since Sessions in Catalyst are global you can use this to reduce per request overhead. On the other hand you may just use this for early prototying and then move onto something else for production. I'm sure you'll do the right thing ;)

The downsides are that you can really only count on about 4Kb of storage space on the cookie. Also, that cookie data becomes part of every request so that will increase overhead on the request side of the network. In other words a big cookie means more data over the wire (maybe you are paying by the byte...?)

Also there are some questions as to the security of this approach. We encrypt information with Session::Storage::Secure so you should review that and the notes that it includes. Using this without SSL/HTTPS is not recommended. Buyer beware.

In any case if all you are putting in the session is a user id and a few basic things this will probably be totally fine and likely a lot more sane that using something non persistant like memcached. On the other hand if you like to dump a bunch of stuff into the user session, this will likely not work out.

NOTE Since we need to store all the session info in the cookie, the session state will be set at ->finalize_headers stage (rather than at ->finalize_body which is the default for session storage plugins). What this means is that if you use the streaming or socket interfaces ($c->response->write, $c->response->write_fh and $c->req->io_fh) your session state will get saved early. For example you cannot do this:

    $c->res->write("some stuff");
    $c->session->{key} = "value";

That key 'key' will not be recalled when the session is recovered for the following request. In general this should be an easy issue to work around, but you need to be aware of it.

CONFIGURATION

This plugin supports the following configuration settings, which are stored as a hash ref under the configuration key 'Plugin::Session::Store::Cookie'. See "SYNOPSIS" for example.

The name of the cookie that stores your session data on the client. Defaults to '${$myapp}_sstore' (where $myappp is the lowercased version of your application subclass). You may wish something less obvious.

How long before the cookie that is storing the session info expires. defaults to '+1d'. Lower is more secure but bigger hassle for your user. You choose the right balance.

storage_secret_key

Used to fill the 'secret_key' initialization parameter for Session::Storage::Secure. Don't let this be something you can guess or something that escapes into the wild...

There is no default for this, you need to supply.

If this attribute set to 0 the cookie will not have the secure flag.

If this attribute set to 1 the cookie sent by the server to the client will get the secure flag that tells the browser to send this cookie back to the server only via HTTPS.

If this attribute set to 2 then the cookie will get the secure flag only if the request that caused cookie generation was sent over https (this option is not good if you are mixing https and http in your application).

Default value is 0.

If this attribute set to 0, the cookie will not have HTTPOnly flag.

If this attribute set to 1, the cookie will got HTTPOnly flag that should prevent client side Javascript accessing the cookie value - this makes some sort of session hijacking attacks significantly harder. Unfortunately not all browsers support this flag (MSIE 6 SP1+, Firefox 3.0.0.6+, Opera 9.5+); if a browser is not aware of HTTPOnly the flag will be ignored.

Default value is 1.

Note1: Many people are confused by the name "HTTPOnly" - it does not mean that this cookie works only over HTTP and not over HTTPS.

Note2: This parameter requires Catalyst::Runtime 5.80005 otherwise is skipped.

This attribute configures the value of the SameSite flag.

If set to None, the cookie will be sent when making cross origin requests, including following links from other origins. This requires the "cookie_secure" flag to be set.

If set to Lax, the cookie will not be included when embedded in or fetched from other origins, but will be included when following cross origin links.

If set to Strict, the cookie will not be included for any cross origin requests, including links from different origins.

Default value is Lax. This is the default modern browsers use.

Note: This parameter requires Catalyst::Runtime 5.90125 otherwise is skipped.

sereal_decoder_options

sereal_encoder_options

This should be a hashref of options passed to init args of same name in Session::Storage::Secure. Defaults to:

    sereal_encoder_options => +{ snappy => 1, stringify_unknown => 1 },
    sereal_decoder_options => +{ validate_utf8 => 1 },

Please note the default allows object serealization. You may wish to not allow this for production setups.

AUTHOR

John Napiorkowski email:jjnapiork@cpan.org Alexander Hartmaier email:abraxxa@cpan.org

SEE ALSO

Catalyst, Catalyst::Plugin::Session, Session::Storage::Secure

COPYRIGHT & LICENSE

Copyright 2022, John Napiorkowski email:jjnapiork@cpan.org

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.