Reconnect when connection is lost

Signed-off-by: Florian Pritz <bluewind@xinu.at>

12 files changed, 301 insertions, 31 deletions

diff --git a/README.md b/README.md
index 6de1231..eb939d1 100644
--- a/README.md
+++ b/README.md
@@ -22,3 +22,20 @@ it under the same terms as Perl itself.
 # AUTHOR
 
 Florian Pritz <bluewind@xinu.at>
+
+### loop\_reconnect
+
+    $app->loop_reconnect();
+
+Same as loop(), but automatcally calls loop() again if the connection is lost.
+
+### loop
+
+    $app->loop();
+
+Open a connection and wait for NOTIFY notifications. When a NOTIFY notification
+arrives, show a notification to the user.
+
+This method throws an exception when the connection to the server is lost. If
+you want to continue waiting for new notifications, you may call this method
+again. Also look at loop\_reconnect().
diff --git a/cpanfile b/cpanfile
index 5f314dd..d650d5c 100644
--- a/cpanfile
+++ b/cpanfile
@@ -3,6 +3,8 @@ requires 'IO::Socket::SSL';
 requires 'Log::Any';
 requires 'Log::Any::Adapter';
 requires 'MCE::Hobo';
+requires 'Path::Tiny';
+requires 'Syntax::Keyword::Try';
 requires 'Time::Out';
 requires 'autodie';
 requires 'perl', 'v5.24.0';
@@ -13,6 +15,7 @@ on configure => sub {
 
 on test => sub {
     requires 'Test::Differences';
+    requires 'Test::Exception';
     requires 'Test::MockObject';
     requires 'Test::More', '0.98';
 };
diff --git a/lib/App/ImapNotify.pm b/lib/App/ImapNotify.pm
index e7aba6f..b7b1cf7 100644
--- a/lib/App/ImapNotify.pm
+++ b/lib/App/ImapNotify.pm
@@ -11,6 +11,7 @@ use App::ImapNotify::Notifier;
 use Carp;
 use Function::Parameters;
 use Log::Any qw($log);
+use Syntax::Keyword::Try;
 
 =encoding utf-8
 
@@ -55,10 +56,47 @@ method new_no_defaults($class: $config, $deps = {}) {
 	return $self;
 }
 
+=head3 loop_reconnect
+
+ $app->loop_reconnect();
+
+Same as loop(), but automatcally calls loop() again if the connection is lost.
+
+=cut
+
+method loop_reconnect() {
+	my $holdoff_time = 10;
+	my $holdoff_repeat = 0;
+	my $holdoff_limit = 300;
+
+	while (1) {
+		my $last_time = time;
+		try {
+			$self->loop();
+		} catch {
+			die $@ unless $@ =~ m/^Lost connection while .*/;
+		}
+		$holdoff_repeat = 0 if (time - $last_time) > $holdoff_limit;
+		sleep($holdoff_time * $holdoff_repeat++);
+	}
+}
+
+=head3 loop
+
+ $app->loop();
+
+Open a connection and wait for NOTIFY notifications. When a NOTIFY notification
+arrives, show a notification to the user.
+
+This method throws an exception when the connection to the server is lost. If
+you want to continue waiting for new notifications, you may call this method
+again. Also look at loop_reconnect().
+
+=cut
+
 method loop() {
-	#my $imap = $self->{deps}->{imap_client}->connect($self->{config}->@{qw(host port log_id)});
-	#$imap->login($self->{config}->@{qw(username password)});
 	my $imap = $self->{deps}->{imap_client};
+	$imap->reconnect();
 	$imap->select($self->{config}->{mailboxes}->@[0]);
 
 	$imap->send_command("notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (".join(' ', $self->{config}->{mailboxes}->@*).") (MessageNew MessageExpunge MailboxName))");
@@ -75,8 +113,6 @@ method loop() {
 			my $mailbox = $+{mailbox};
 			my $uid = $+{uidnext} - 1;
 			$log->debugf("Got status change: '%s'", $line =~ s/\r\n$//r);
-			#$imap2->select($mailbox);
-			#my $message = $imap2->send_command("uid fetch $uid (body.peek[header.fields (from to subject)])");
 			$imap->select($mailbox);
 			my $message = $imap->send_command("uid fetch $uid (body.peek[header.fields (from to subject)])");
 			pop @{$message};
diff --git a/lib/App/ImapNotify/ImapClient.pm b/lib/App/ImapNotify/ImapClient.pm
index 6e5e21b..ae91c78 100644
--- a/lib/App/ImapNotify/ImapClient.pm
+++ b/lib/App/ImapNotify/ImapClient.pm
@@ -53,27 +53,33 @@ method new_no_defaults($class: $config, $deps = {}) {
 	$self->{keepalive_timeout} = $config->{keepalive_timeout};
 	$self->{line_buffer} = [];
 	$self->{deps} = $deps;
-	$self->_connect();
-	$self->_login($config->@{qw(username password)});
+	$self->{config} = $config;
 	return $self;
 }
 
-method _connect() {
-	# wait for server greeting
+method reconnect() {
+	$self->{command_counter} = 0;
+	$self->{deps}->{sock}->reconnect();
 	my $response = $self->readline_block();
+	croak("Lost connection while waiting for server greeting") if not defined $response;
+
 	if ($response !~ m/^\* OK (.*)/) {
-		confess "Invalid server greeting. Got reply: $response";
+		confess "Invalid server greeting. Got reply: '$response'";
 	}
 
 	$self->{capabilities} = $1;
+
+	$self->_login();
 }
 
-method _login($username, $password) {
+method _login() {
 	if ($self->{capabilities} !~ m/\bAUTH=PLAIN\b/) {
 		croak "Server doesn't support AUTH=PLAIN";
 	}
 
-	my $response = $self->send_command("login $username $password");
+	my $response = $self->send_command("login $self->{config}->{username} $self->{config}->{password}");
+	return if not defined $response;
+
 	confess "No capabilities found in response: '".$response->[0]."'" unless $response->[0] =~ m/^OK \[(.*)\].*$/;
 	$self->{capabilities} = $1;
 
@@ -92,15 +98,10 @@ method select($mailbox) {
 
 
 method send_command($command) {
-	state $counter = 0;
-
-	my $id = "CMD-".$counter++;
+	my $id = "CMD-".$self->{command_counter}++;
 
 	chomp($command);
 
-	#print "Sending $command\n";
-	#sleep (5) if $command eq "noop";
-
 	$self->writeline("$id $command\r\n");
 
 	my @lines;
@@ -125,8 +126,10 @@ method send_command($command) {
 		if ($line =~ /^(.*\r\n)$/) {
 			push @lines, $1;
 		}
-
 	}
+
+	croak("Lost connection while waiting for reply to command '$command'");
+	return;
 }
 
 method get_uids($mailbox) {
diff --git a/lib/App/ImapNotify/Socket/SSL.pm b/lib/App/ImapNotify/Socket/SSL.pm
index 18d7ffa..2654cdc 100644
--- a/lib/App/ImapNotify/Socket/SSL.pm
+++ b/lib/App/ImapNotify/Socket/SSL.pm
@@ -8,24 +8,26 @@ use Function::Parameters;
 use IO::Socket::SSL;
 use Log::Any qw($log);
 
-method new($class: $host, $port, $deps = {}) {
-	$deps->{sock} //= IO::Socket::SSL->new("$host:$port");
-	return $class->new_no_defaults($deps);
-}
-
-method new_no_defaults($class: $deps = {}) {
+method new($class: $host, $port) {
 	my $self = {};
+	$self->{config} = {
+		host => $host,
+		port => $port,
+	};
 	bless $self, $class;
-	$self->{deps} = $deps;
 	return $self;
 }
 
+method reconnect() {
+	$self->{sock} = IO::Socket::SSL->new("$self->{config}->{host}:$self->{config}->{port}");
+}
+
 method readline() {
-	return CORE::readline $self->{deps}->{sock};
+	return CORE::readline $self->{sock};
 }
 
 method writeline($line) {
-	print {$self->{deps}->{sock}} $line;
+	print {$self->{sock}} $line;
 }
 
 
diff --git a/script/imap-notify.pl b/script/imap-notify.pl
index d540e76..234c5e8 100755
--- a/script/imap-notify.pl
+++ b/script/imap-notify.pl
@@ -101,7 +101,7 @@ for my $single_conf ($config->{watches}->@*) {
 	$single_conf->{password} = `$single_conf->{passwordeval}`;
 	push @workers, mce_async {
 		my $app = App::ImapNotify->new($single_conf);
-		$app->loop();
+		$app->loop_reconnect();
 	}
 }
 
diff --git a/t/01_basic.t b/t/01_basic.t
index 6f9d076..7afc839 100644
--- a/t/01_basic.t
+++ b/t/01_basic.t
@@ -31,7 +31,7 @@ $socket->set_series('readline',
 	")\r\n",
 );
 
-$socket->set_true(qw(writeline));
+$socket->set_true(qw(writeline reconnect));
 
 my $config = {
 	log_id => 'test-id1',
diff --git a/t/02_noop.t b/t/02_noop.t
index f1d4ab5..d479efc 100644
--- a/t/02_noop.t
+++ b/t/02_noop.t
@@ -39,7 +39,7 @@ my @input_lines = (
 
 my $socket = Test::MockObject->new();
 $socket->mock('readline', sub {my $x = shift @input_lines; ref($x) eq "CODE" ? $x->() : $x;});
-$socket->set_true(qw(writeline));
+$socket->set_true(qw(writeline reconnect));
 
 my $config = {
 	log_id => 'test-id1',
diff --git a/t/03_other_mailbox.t b/t/03_other_mailbox.t
index a1ef59a..443fc68 100644
--- a/t/03_other_mailbox.t
+++ b/t/03_other_mailbox.t
@@ -47,7 +47,7 @@ my @input_lines = (
 
 my $socket = Test::MockObject->new();
 $socket->mock('readline', sub {my $x = shift @input_lines; ref($x) eq "CODE" ? $x->() : $x;});
-$socket->set_true(qw(writeline));
+$socket->set_true(qw(writeline reconnect));
 
 my $config = {
 	log_id => 'test-id1',
diff --git a/t/04_reconnect.t b/t/04_reconnect.t
new file mode 100644
index 0000000..987db8e
--- /dev/null
+++ b/t/04_reconnect.t
@@ -0,0 +1,66 @@
+use strict;
+use warnings;
+use Test::Differences;
+use Test::More;
+use Test::MockObject;
+
+use Log::Any::Adapter ('Stderr', log_level => "warn");
+
+use App::ImapNotify;
+use App::ImapNotify::ImapClient;
+
+=head1 DESCRIPTION
+
+Simulate a connection loss (readline on socket returns undef).
+
+=cut
+
+my @input_lines = (
+	"* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ AUTH=PLAIN AUTH=LOGIN] Fake server ready.\r\n",
+	"CMD-0 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY LITERAL+ NOTIFY SPECIAL-USE COMPRESS=DEFLATE] Logged in\r\n",
+	"CMD-1 OK [READ-WRITE] Select completed (0.001 + 0.000 secs).\r\n",
+	"CMD-2 OK NOTIFY completed (0.001 + 0.000 secs).\r\n",
+	# "connection loss"
+	undef,
+	# client should reconnect
+	"* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ AUTH=PLAIN AUTH=LOGIN] Fake server ready.\r\n",
+	"CMD-0 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY LITERAL+ NOTIFY SPECIAL-USE COMPRESS=DEFLATE] Logged in\r\n",
+	"CMD-1 OK [READ-WRITE] Select completed (0.001 + 0.000 secs).\r\n",
+	"CMD-2 OK NOTIFY completed (0.001 + 0.000 secs).\r\n",
+);
+
+my $socket = Test::MockObject->new();
+$socket->mock('readline', sub {my $x = shift @input_lines; ref($x) eq "CODE" ? $x->() : $x;});
+$socket->set_true(qw(writeline reconnect));
+
+my $config = {
+	log_id => 'test-id1',
+	host => 'localhost.localdomain',
+	port => 993,
+	username => 'tester1',
+	password => 'secretPW42',
+	mailboxes => [qw(INBOX INBOX.test)],
+	keepalive_timeout => 300,
+};
+
+my $imap_client = App::ImapNotify::ImapClient->new_no_defaults($config, {sock => $socket});
+
+my $app = App::ImapNotify->new_no_defaults($config, {imap_client => $imap_client});
+
+$app->loop();
+$app->loop();
+
+is(scalar(@input_lines), 0, "all input lines are read");
+
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+		['writeline', [$socket, "CMD-2 notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (INBOX INBOX.test) (MessageNew MessageExpunge MailboxName))\r\n"]],
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+		['writeline', [$socket, "CMD-2 notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (INBOX INBOX.test) (MessageNew MessageExpunge MailboxName))\r\n"]],
+	], "socket writeline is called correctly");
+
+is(scalar(grep { $_->[0] eq "reconnect" } $socket->_calls()->@*), 2, "socket reconnect is called twice");
+
+done_testing;
diff --git a/t/05_reconnect_noop.t b/t/05_reconnect_noop.t
new file mode 100644
index 0000000..008b461
--- /dev/null
+++ b/t/05_reconnect_noop.t
@@ -0,0 +1,70 @@
+use strict;
+use warnings;
+use Test::Differences;
+use Test::More;
+use Test::MockObject;
+use Test::Exception;
+
+use Log::Any::Adapter ('Stderr', log_level => "warn");
+
+use App::ImapNotify;
+use App::ImapNotify::ImapClient;
+
+=head1 DESCRIPTION
+
+Simulate a connection loss when sending noop (readline on socket returns undef).
+
+=cut
+
+my @input_lines = (
+	"* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ AUTH=PLAIN AUTH=LOGIN] Fake server ready.\r\n",
+	"CMD-0 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY LITERAL+ NOTIFY SPECIAL-USE COMPRESS=DEFLATE] Logged in\r\n",
+	"CMD-1 OK [READ-WRITE] Select completed (0.001 + 0.000 secs).\r\n",
+	"CMD-2 OK NOTIFY completed (0.001 + 0.000 secs).\r\n",
+	# wait for client to send noop
+	sub {sleep 10; fail("Keepalive failed to kill readline() operation");},
+	# "connection loss"
+	undef,
+	# client should reconnect
+	"* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ AUTH=PLAIN AUTH=LOGIN] Fake server ready.\r\n",
+	"CMD-0 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY LITERAL+ NOTIFY SPECIAL-USE COMPRESS=DEFLATE] Logged in\r\n",
+	"CMD-1 OK [READ-WRITE] Select completed (0.001 + 0.000 secs).\r\n",
+	"CMD-2 OK NOTIFY completed (0.001 + 0.000 secs).\r\n",
+);
+
+my $socket = Test::MockObject->new();
+$socket->mock('readline', sub {my $x = shift @input_lines; ref($x) eq "CODE" ? $x->() : $x;});
+$socket->set_true(qw(writeline reconnect));
+
+my $config = {
+	log_id => 'test-id1',
+	host => 'localhost.localdomain',
+	port => 993,
+	username => 'tester1',
+	password => 'secretPW42',
+	mailboxes => [qw(INBOX INBOX.test)],
+	keepalive_timeout => 0.01,
+};
+
+my $imap_client = App::ImapNotify::ImapClient->new_no_defaults($config, {sock => $socket});
+
+my $app = App::ImapNotify->new_no_defaults($config, {imap_client => $imap_client});
+
+throws_ok {$app->loop();} qr/^Lost connection while waiting for reply to command 'noop'/, "Expect connection loss";
+$app->loop();
+
+is(scalar(@input_lines), 0, "all input lines are read");
+
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+		['writeline', [$socket, "CMD-2 notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (INBOX INBOX.test) (MessageNew MessageExpunge MailboxName))\r\n"]],
+		['writeline', [$socket, "CMD-3 noop\r\n"]],
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+		['writeline', [$socket, "CMD-2 notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (INBOX INBOX.test) (MessageNew MessageExpunge MailboxName))\r\n"]],
+	], "socket writeline is called correctly");
+
+is(scalar(grep { $_->[0] eq "reconnect" } $socket->_calls()->@*), 2, "socket reconnect is called twice");
+
+done_testing;
diff --git a/t/06_early_connection_loss.t b/t/06_early_connection_loss.t
new file mode 100644
index 0000000..105ea29
--- /dev/null
+++ b/t/06_early_connection_loss.t
@@ -0,0 +1,73 @@
+use strict;
+use warnings;
+use Test::Differences;
+use Test::More;
+use Test::MockObject;
+use Test::Exception;
+
+use Log::Any::Adapter ('Stderr', log_level => "trace");
+
+use App::ImapNotify;
+use App::ImapNotify::ImapClient;
+
+=head1 DESCRIPTION
+
+Simulate a connection loss during early stages of the connection.
+
+=cut
+
+my @input_lines = (
+	"* OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ AUTH=PLAIN AUTH=LOGIN] Fake server ready.\r\n",
+	"CMD-0 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY LITERAL+ NOTIFY SPECIAL-USE COMPRESS=DEFLATE] Logged in\r\n",
+	"CMD-1 OK [READ-WRITE] Select completed (0.001 + 0.000 secs).\r\n",
+	"CMD-2 OK NOTIFY completed (0.001 + 0.000 secs).\r\n",
+);
+
+my $socket = Test::MockObject->new();
+$socket->set_true(qw(writeline reconnect));
+
+my $config = {
+	log_id => 'test-id1',
+	host => 'localhost.localdomain',
+	port => 993,
+	username => 'tester1',
+	password => 'secretPW42',
+	mailboxes => [qw(INBOX INBOX.test)],
+	keepalive_timeout => 300,
+};
+
+my $imap_client = App::ImapNotify::ImapClient->new_no_defaults($config, {sock => $socket});
+
+my $app = App::ImapNotify->new_no_defaults($config, {imap_client => $imap_client});
+
+$socket->set_series('readline',	undef);
+throws_ok {$app->loop();} qr/^Lost connection while waiting for server greeting/, "Expect connection loss";
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+	], "Connection loss before receiving greeting");
+$socket->clear();
+
+$socket->set_series('readline',	@input_lines[0..0], undef);
+throws_ok {$app->loop();} qr/^Lost connection while waiting for reply to command 'login tester1 secretPW42'/, "Expect connection loss";
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+	], "Connection loss after sending login");
+$socket->clear();
+
+$socket->set_series('readline',	@input_lines[0..1], undef);
+throws_ok {$app->loop();} qr/^Lost connection while waiting for reply to command 'select INBOX'/, "Expect connection loss";
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+	], "Connection loss after sending select");
+$socket->clear();
+
+$socket->set_series('readline',	@input_lines[0..2], undef);
+throws_ok {$app->loop();} qr/^Lost connection while waiting for reply to command 'notify set \(.*\)'/, "Expect connection loss";
+eq_or_diff([grep { $_->[0] eq "writeline" } $socket->_calls()->@*], [
+		['writeline', [$socket, "CMD-0 login tester1 secretPW42\r\n"]],
+		['writeline', [$socket, "CMD-1 select INBOX\r\n"]],
+		['writeline', [$socket, "CMD-2 notify set (selected (MessageExpunge MessageNew (uid body.peek[header.fields (from to subject)]))) (mailboxes (INBOX INBOX.test) (MessageNew MessageExpunge MailboxName))\r\n"]],
+	], "Connection loss after sending notify");
+$socket->clear();
+
+done_testing;