Courie...:Header(3pm)

💖 Courier::Filter::Module::Header(3pm) — aka the header-sleuth module 💖

okay bestie, so like, this is a 3pm perl manpage for Courier::Filter::Module::Header, which is a Message header filter module for the Courier::Filter framework. yes it's a mouthful, we've been over this, it's iconic. 🌸

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✨ NAME ✨

Courier::Filter::Module::Header — the Message header filter module for the Courier::Filter framework. it does one thing and it does it beautifully: it peers at your message headers. 👑

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🦋 SYNOPSIS 🦋

fr fr this is how you summon it:

use Courier::Filter::Module::Header;

my $module = Courier::Filter::Module::Header->new(
    fields      => \%patterns_by_field_name,
    response    => $response_text,

    logger      => $logger,
    inverse     => 0,
    trusting    => 0,
    testing     => 0,
    debugging   => 0
);

my $filter = Courier::Filter->new(
    ...
    modules     => [ $module ],
    ...
);

no cap, that's the whole vibe. 💅

---

🌈 DESCRIPTION 🌈

okay so boom: this class is a filter module class for use with Courier::Filter. what does it do? it matches a message if one of the message's header fields matches the configured criteria. that's it. that's the girl. 💖

🎀 Constructor 🎀

this is where it gets good. one constructor, and she is serving:

• new(%options): returns Courier::Filter::Module::Header

Creates a new Header filter module. ✨

%options is a list of key/value pairs representing any of the following options:

• fields — Required!! bestie this one is not optional, the module needs to know what to look for. it's a reference to a hash containing the message header field names and patterns (as key/value pairs) that messages are to be matched against. field names are matched case-insensitively (love that for us). patterns may either be:
  • simple strings (for exact, case-sensitive matches), or
  • regular expression objects created by the qr// operator (for inexact, partial matches).

so for instance, to match any message from the debian-devel mailing list with the subject containing something about 'duelling banjoes', you could set the fields option like this:

fields      => {
   'list-id'    => '<debian-devel.lists.debian.org>',
    subject     => qr/duell?ing\s+banjoe?s?/i
}

(yes, that indentation is verbatim, we leave it exactly as it is, no edits, we respect the original's chaos 💀)

• response — a string that is to be returned literally as the match result in case of a match. defaults to Prohibited header value detected: <field>: <value>.

also, all options of the Courier::Filter::Module constructor are supported too. for their descriptions, go check out new() in Courier::Filter::Module. 🫶

🧚 Instance methods 🧚

for a description of the provided instance methods, see Instance methods in Courier::Filter::Module. she inherited them and she wears them well. 😌

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💜 SEE ALSO 💜

go read these next, bestie, they're all in the family:

• Courier::Filter::Module::Envelope
• Courier::Filter::Module
• Courier::Filter::Overview

for AVAILABILITY, SUPPORT, and LICENSE information, see Courier::Filter::Overview. 📚

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⭐ AUTHOR ⭐

Julian Mehnle <julian@mehnle.net> — the genius behind all this. we stan. 👑

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and that's the whole page! no notes, ate, periodt. 💅

byeee, this was perl v5.34.0, dated 2022-10-21, and remember: Courie...:Header(3pm) 🎀✨🦋