POD for ::MailStore::FS

1 files changed, 110 insertions, 4 deletions

diff --git a/lib/Sietima/MailStore/FS.pm b/lib/Sietima/MailStore/FS.pm
index adc1c03..d34b388 100644
--- a/lib/Sietima/MailStore/FS.pm
+++ b/lib/Sietima/MailStore/FS.pm
@@ -11,8 +11,38 @@ use namespace::clean;
 # VERSION
 # ABSTRACT: filesystem-backed email store
 
+=head1 SYNOPSIS
+
+  my $store = Sietima::MailStore::FS->new({ root => '/tmp/my-store' });
+
+=head1 DESCRIPTION
+
+This class implements the L<< C<Sietima::MailStore> >> interface,
+storing emails as files on disk.
+
+=cut
+
 with 'Sietima::MailStore';
 
+=attr C<root>
+
+Required, a L<< C<Path::Tiny> >> object that points to an existing
+directory. Coercible from a string.
+
+It's a good idea for the directory to be readable and writable by the
+user who will run the mailing list, and also by all users who will run
+administrative commands (like those provided by L<<
+C<Sietima::Role::SubscriberOnly::Moderate> >>). A way to achieve that
+is to have a group dedicated to list owners, and set the directory
+group-writable and group-sticky, and owned by that group:
+
+  # chgrp-R mailinglists /tmp/my-store
+  # chmod -R g+rwXs /tmp/my-store
+
+=for Pod::Coverage BUILD
+
+=cut
+
 has root => (
     is => 'ro',
     required => 1,
@@ -29,10 +59,18 @@ sub BUILD($self,@) {
     return;
 }
 
-sub clear($self) {
-    do { $self->$_->remove_tree;$self->$_->mkpath } for qw(_tagdir _msgdir);
-    return;
-}
+=head2 C<store>
+
+  my $id = $store->store($email_mime_object,@tags);
+
+Stores the given email message inside the L<store root|/root>, and
+associates with the given tags.
+
+Returns a unique identifier for the stored message. If you store twice
+the same message (or two messages that stringify identically), you'll
+get the same identifier.
+
+=cut
 
 sub store($self,$mail,@tags) {
     state $check = compile(Object,EmailMIME,slurpy ArrayRef[TagName]);$check->(@_);
@@ -47,6 +85,19 @@ sub store($self,$mail,@tags) {
     return $id;
 }
 
+=head2 C<retrieve_by_id>
+
+  my $email_mime_object = $store->retrieve_by_id($id);
+
+Given an identifier returned by L<< /C<store> >>, this method returns
+the email message.
+
+If the message has been deleted, or the identifier is not recognised,
+this method returns C<undef> in scalar context, or an empty list in
+list context.
+
+=cut
+
 sub retrieve_by_id($self,$id) {
     state $check = compile(Object,Str);$check->(@_);
 
@@ -55,6 +106,20 @@ sub retrieve_by_id($self,$id) {
     return Email::MIME->new($msg_path->slurp_raw);
 }
 
+=head2 C<retrieve_ids_by_tags>
+
+  my @ids = $store->retrieve_ids_by_tags(@tags)->@*;
+
+Given a list of tags, this method returns an arrayref containing the
+identifiers of all (and only) the messages that were stored associated
+with (at least) all those tags. The order of the returned identifiers
+is essentially random.
+
+If there are no messages associated with the given tags, this method
+returns an empty arrayref.
+
+=cut
+
 sub _tagged_by($self,$tag) {
     my $tag_file = $self->_tagdir->child($tag);
     return unless -e $tag_file;
@@ -64,6 +129,7 @@ sub _tagged_by($self,$tag) {
 sub retrieve_ids_by_tags($self,@tags) {
     state $check = compile(Object,slurpy ArrayRef[TagName]);$check->(@_);
 
+    # this maps: id -> how many of the given @tags it has
     my %msgs;
     if (@tags) {
         for my $tag (@tags) {
@@ -76,12 +142,28 @@ sub retrieve_ids_by_tags($self,@tags) {
 
     my @ret;
     for my $id (keys %msgs) {
+        # if this message id does not have all the required tags, we
+        # won't return it
         next unless $msgs{$id} == @tags;
         push @ret, $id;
     }
     return \@ret;
 }
 
+=head2 C<retrieve_by_tags>
+
+  my @email_mime_objects = $store->retrieve_by_tags(@tags)->@*;
+
+This method is similar to L<< /C<retrieve_ids_by_tags> >>, but it
+returns an arrayref of hashrefs like:
+
+ $store->retrieve_ids_by_tags('t1') ==> [
+   { id => $id1, mail => $msg1 },
+   { id => $id2, mail => $msg2 },
+  ]
+
+=cut
+
 sub retrieve_by_tags($self,@tags) {
     state $check = compile(Object,slurpy ArrayRef[TagName]);$check->(@_);
 
@@ -96,6 +178,15 @@ sub retrieve_by_tags($self,@tags) {
     return \@ret;
 }
 
+=head2 C<remove>
+
+  $store->remove($id);
+
+This method removes the message corresponding to the given identifier
+from disk. Removing a non-existent message does nothing.
+
+=cut
+
 sub remove($self,$id) {
     state $check = compile(Object,Str);$check->(@_);
 
@@ -107,4 +198,19 @@ sub remove($self,$id) {
     return;
 }
 
+=method C<clear>
+
+  $store->clear();
+
+This method removes all messages from disk. Clearing as empty store
+does nothing.
+
+
+=cut
+
+sub clear($self) {
+    do { $self->$_->remove_tree;$self->$_->mkpath } for qw(_tagdir _msgdir);
+    return;
+}
+
 1;