use v6;
use Crust::Middleware;

unit class Crust::Middleware::Lint is Crust::Middleware;

my sub validate-env(%env) {
    unless %env<REQUEST_METHOD> {
        die 'Missing env param: REQUEST_METHOD';
    }
    unless %env<REQUEST_METHOD> ~~ /^<[A..Z]>+$/ {
        die "Invalid env param: REQUEST_METHOD(%env<REQUEST_METHOD>)";
    }
    unless %env<SCRIPT_NAME>.defined { # allows empty string
        die 'Missing mandatory env param: SCRIPT_NAME';
    }
    if %env<SCRIPT_NAME> eq '/' {
        die 'SCRIPT_NAME must not be /';
    }
    unless %env<PATH_INFO>.defined { # allows empty string
        die 'Missing mandatory env param: PATH_INFO';
    }
    if %env<PATH_INFO> ne '' && %env<PATH_INFO> !~~ m!^'/'! {
        die "PATH_INFO must begin with / (%env<PATH_INFO>)";
    }
    unless %env<SERVER_NAME>.defined {
        die 'Missing mandatory env param: SERVER_NAME';
    }
    if %env<SERVER_NAME> eq '' {
        die 'SERVER_NAME must not be empty string';
    }
    unless %env<SERVER_PORT>.defined {
        die 'Missing mandatory env param: SERVER_PORT';
    }
    if %env<SERVER_PORT> eq '' {
        die 'SERVER_PORT must not be empty string';
    }
    if %env<SERVER_PROTOCOL>.defined && %env<SERVER_PROTOCOL> !~~ m{^HTTP'/'\d} {
        die "Invalid SERVER_PROTOCOL: %env<SERVER_PROTOCOL>";
    }

    # TODO validate p6w.xxx

    if %env<HTTP_CONTENT_TYPE> {
        die 'HTTP_CONTENT_TYPE should not exist';
    }
    if %env<HTTP_CONTENT_LENGTH> {
        die 'HTTP_CONTENT_LENGTH should not exist';
    }
}

my sub validate-ret(@ret) {
    unless @ret == 3 {
        die 'Response needs to be 3 element array';
    }

    unless @ret[0] ~~ /^\d+$/ && @ret[0] >= 100 {
        die "Status code needs to be an integer greater than or equal to 100: @ret[0]";
    }

    unless @ret[1].isa(List) {
        die "Headers needs to be an list: @ret[1]";
    }
    my $copy = @ret[1];
    {
	our %this-copy = $copy;
        %this-copy.pairup();
        CATCH {
            default {
                die 'The number of response headers needs to be even, not odd(', $copy, ')';
            }
        }
    }

    for $copy.kv -> $i, $v {
        my ($key, $val) = $v.kv;

        if $key.lc eq 'status' {
            die 'Response headers MUST NOT contain a key named Status';
        }
        if $key ~~ /[<[: \r \n]> | <[- _]>]$/ {
            die "Response headers MUST NOT contain a key with : or newlines, or that end in - or _: $key";
        }
        unless $key ~~ /^<[a..z A..Z]><[0..9 a..z A..Z \- _]>*$/ {
            die "Response headers MUST consist only of letters, digits, _ or - and MUST start with a letter: $key";
        }

        unless $val.defined {
            die 'Response headers MUST be a defined string';
        }

        if $val ~~ /<[\o00..\o37]>/ {
            die "Response headers MUST NOT contain characters below octal \o37: $val";
        }
    }

    my $res-body = @ret[2];
    unless $res-body.isa(List) || $res-body.isa(Supply) || $res-body.isa(Channel) || $res-body.isa(IO::Handle) {
        die 'Body is not suitable type: ' ~ $res-body.WHAT.perl;
    }

    return @ret;
}

method CALL-ME(%env) {
    validate-env(%env);
    my $ret = $.app()(%env);
    unless $ret.isa(Promise) {
        die "P6W app's return value must be a Promise: " ~ $ret.WHAT.perl;
    }
    my @ret = await $ret;
    return start { validate-ret(@ret) };
}



head

Crust::Middleware::Lint - Validate request and response


my $app = sub { ... }; # your app
$app = Crust::Middleware::Lint.new($app);


Crust::Middleware::Lint is a middleware component to validate request
and response environment formats. You are strongly suggested to use
this middleware when you develop a new framework adapter or a new P6W
web server that implements the P6W interface.


This middleware is inspired by L<Plack::Middleware::Lint|https://metacpan.org/pod/Plack::Middleware::Lint> and most of code is taken from that.


root

ReverseProxy

ErrorDocument

React

=begin React :component<HeaderCol> :id<menu> 
=para L<Documentation|/doc/introduction>
=para L<Modules| /mods>
=para L<Examples| file:../examples/index.podlite>
=para L<Download |file:../download/index.podlite>
=para L<About|file:../about/index.podlite>
=para 🔍 K<⌘K>/K<ctrl-K>
=end React


=begin React :component<HeaderCol> :id<footer>  
=begin nested :!nested
=item1 B<Language>
    =item2 L<Get started|file:../getting-started/getting-started.podlite>
    =item2 L<Why Raku?|/doc/language/faq#Why-should-I-learn-Raku-What's-so-great-about-it>
    =item2 L<Try Raku|https://glot.io/new/raku>
    =item2 L<Raku cheat sheet|https://github.com/Raku/mu/blob/master/docs/Perl6/Cheatsheet/cheatsheet.txt>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<Raku on Exercism|https://exercism.org/tracks/raku>
    =item2 L<Wikipedia|https://en.wikipedia.org/wiki/Raku_(programming_language)>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=end nested
=begin nested :!nested

=item1 B<L<Documentation|/doc>>
    =item2 L<Getting started, Migration guides from other languages, & Tutorials | file:../doc/introduction.podlite>
    =item2 L<Language References|file:../doc/reference.podlite>
    =item2 L<Type Reference| file:../doc/types.podlite>
    =item2 L<Miscellaneous| file:../doc/miscellaneous.podlite>
    =item2 L<FAQs (Frequently Asked Questions)|/doc/language/faq>
    =item2 L<Community|/doc/language/community>
    =item2 L<The list of all documents|file:../doc/index.podlite>

=item1 B<Resources>
    =item2 L<The Raku Guide|https://raku.guide/>
    =item2 L<Books |https://perl6book.com/>
    =item2 L<Rosetta Code | https://www.raku.org/community/rosettacode>

=end nested
=begin nested :!nested

=item1 B<Resoures>
    =item2 L<Download | file:../download/index.podlite>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=item1 B<Learning>
    =item2 L<The Raku Guide|https://raku.guide/>
    =item2 L<Wikibook |https://en.wikibooks.org/wiki/Raku_Programming>
    =item2 L<Books |https://perl6book.com/>
    =item2 L<Rosetta Code | https://www.raku.org/community/rosettacode>
    =item2 L<Learn Raku in Y minutes|https://learnxinyminutes.com/docs/raku/>
    =item2 L<Golfing |https://github.com/AlexDaniel/raku-golf-cheatsheet>
=end nested
=begin nested :!nested

=item1 B<Explore>
    =item2 L<Raku Blog Aggregator|https://planet.raku.org/>
    =item2 L<Rakudo Weekly|https://rakudoweekly.blog/>
    =item2 L<The Weekly Challenge |https://perlweeklychallenge.org/>
    =item2 L<Raku Advent Calendar|https://raku-advent.blog/>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>
    =item2 L<empty|#>

=end nested
=end React


=begin React :component<CookieConsent> :id<CookieConsent> :buttonCaption("Got it!")
=para
This website uses cookies for analytics.
=end React


Lint

NAME

SYNOPSIS

DESCRIPTION

AUTHOR