Bug 20582: Turn Koha into a Mojolicious application

This patch is a proof-of-concept of Koha as a Mojolicious application

This has several benefits:
- Development setup is easier. No need for apache or nginx. Just run
  `morbo bin/intranet` or `morbo bin/opac` and go to
  http://localhost:3000 (URL rewrites and static files are handled by
  the app)
- apache2/nginx configuration is simpler too (an example of nginx
  configuration is included in the patch)
- starman and plack middlewares can still be used for debug or gzip
  compression for instance (see app.psgi)
- Using Test::Mojo we can test the whole application, as we do with the
  REST API (which is a Mojolicious application too)
- It opens a way for converting CGI scripts into Mojolicious
  controllers and actions (even if that's not possible at the moment
  because of the authentication code)

It uses the same mechanism as Plack::App::CGIBin to deal with CGI
scripts, so it should be equivalent in terms of performance

How to test ?
- Run `morbo bin/intranet`, then go to http://localhost:3000/ and try to
  find bugs. Check the REST API at http://localhost:3000/api/v1
- Run `morbo bin/opac`, then go to http://localhost:3000/ and try to
  find bugs. Check the REST API at http://localhost:3000/api/v1
- Run `starman -l :5000 -l :5001` and verify that intranet
  (http://localhost:5000) and opac (http://localhost:5001) work normally
- Read the code (and the comments), it's not very long

Signed-off-by: Jerome Charaoui <jcharaoui@cmaisonneuve.qc.ca>
Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>

Koha/App/Intranet.pm

@@ -0,0 +1,85 @@
+package Koha::App::Intranet;
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Mojo::Base 'Mojolicious';
+
+use Koha::Caches;
+use Koha::Cache::Memory::Lite;
+
+sub startup {
+    my ($self) = @_;
+
+    push @{$self->plugins->namespaces}, 'Koha::App::Plugin';
+    push @{$self->static->paths}, $self->home->rel_file('koha-tmpl');
+
+    # Create route for all CGI scripts, need to be loaded first because of
+    # CGI::Compile
+    $self->plugin('CGIBinKoha');
+
+    # Create routes for API
+    # FIXME This generates routes like this: /api/api/v1/...
+    $self->plugin('RESTV1');
+
+    $self->hook(before_dispatch => \&_before_dispatch);
+    $self->hook(around_action => \&_around_action);
+
+    my $r = $self->routes;
+
+    $r->any('/')->to(cb => sub { shift->redirect_to('/cgi-bin/koha/mainpage.pl') });
+}
+
+sub _before_dispatch {
+    my $c = shift;
+
+    my $path = $c->req->url->path->to_string;
+
+    # Remove Koha version from URL
+    $path =~ s/_\d{2}\.\d{7}\.(js|css)/.$1/;
+
+    # See FIXME above
+    if ($path =~ m|^/api/v|) {
+        $path = '/api' . $path;
+    }
+
+    $c->req->url->path->parse($path);
+}
+
+sub _around_action {
+    my ($next, $c, $action, $last) = @_;
+
+    # Flush memory caches before every request
+    my $caches = $Koha::Caches::singleton_caches;
+    if ($caches) {
+        foreach my $key (keys %$caches) {
+            my $cache = $caches->{$key};
+            if (ref $cache->{cache} eq 'Cache::Memory') {
+                $cache->flush_all;
+            }
+            $cache->flush_L1_cache;
+        }
+    }
+    $Koha::Caches::singleton_caches = {};
+    Koha::Cache::Memory::Lite->flush();
+
+    return $next->();
+}
+
+1;

Koha/App/Opac.pm

@@ -0,0 +1,85 @@
+package Koha::App::Opac;
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Mojo::Base 'Mojolicious';
+
+use Koha::Caches;
+use Koha::Cache::Memory::Lite;
+
+sub startup {
+    my ($self) = @_;
+
+    push @{$self->plugins->namespaces}, 'Koha::App::Plugin';
+    push @{$self->static->paths}, $self->home->rel_file('koha-tmpl');
+
+    # Create route for all CGI scripts, need to be loaded first because of
+    # CGI::Compile
+    $self->plugin('CGIBinKoha', opac => 1);
+
+    # Create routes for API
+    # FIXME This generates routes like this: /api/api/v1/...
+    $self->plugin('RESTV1');
+
+    $self->hook(before_dispatch => \&_before_dispatch);
+    $self->hook(around_action => \&_around_action);
+
+    my $r = $self->routes;
+
+    $r->any('/')->to(cb => sub { shift->redirect_to('/cgi-bin/koha/opac-main.pl') });
+}
+
+sub _before_dispatch {
+    my $c = shift;
+
+    my $path = $c->req->url->path->to_string;
+
+    # Remove Koha version from URL
+    $path =~ s/_\d{2}\.\d{7}\.(js|css)/.$1/;
+
+    # See FIXME above
+    if ($path =~ m|^/api/v|) {
+        $path = '/api' . $path;
+    }
+
+    $c->req->url->path->parse($path);
+}
+
+sub _around_action {
+    my ($next, $c, $action, $last) = @_;
+
+    # Flush memory caches before every request
+    my $caches = $Koha::Caches::singleton_caches;
+    if ($caches) {
+        foreach my $key (keys %$caches) {
+            my $cache = $caches->{$key};
+            if (ref $cache->{cache} eq 'Cache::Memory') {
+                $cache->flush_all;
+            }
+            $cache->flush_L1_cache;
+        }
+    }
+    $Koha::Caches::singleton_caches = {};
+    Koha::Cache::Memory::Lite->flush();
+
+    return $next->();
+}
+
+1;

Koha/App/Plugin/CGIBinKoha.pm

@@ -0,0 +1,100 @@
+package Koha::App::Plugin::CGIBinKoha;
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Mojo::Base 'Mojolicious::Plugin';
+
+use CGI::Compile;
+use CGI::Emulate::PSGI;
+use IO::Scalar;
+
+sub register {
+    my ($self, $app, $conf) = @_;
+
+    my $opac = $conf->{opac};
+
+    my $r = $app->routes;
+
+    $r->any('/cgi-bin/koha/*script' => sub {
+        my ($c) = @_;
+
+        my $script = $c->stash('script');
+
+        # Special case for installer which can takes a long time
+        $c->inactivity_timeout(300) if $script eq 'installer/install.pl';
+
+        # Remove trailing slash, if any (e.g. .../svc/config/systempreferences/)
+        $script =~ s|/$||;
+
+        if ($opac) {
+            $script = "opac/$script";
+        }
+
+        unless (-e $c->app->home->rel_file($script)) {
+            return $c->reply->not_found;
+        }
+
+        my $sub = CGI::Compile->compile($script);
+        my $app = CGI::Emulate::PSGI->handler($sub);
+        my $response = $app->($self->_psgi_env($c));
+
+        $c->res->code($response->[0]);
+        $c->res->headers->from_hash({ @{ $response->[1] } });
+        $c->res->body(join('', @{$response->[2]}));
+        $c->rendered;
+    })->name('cgi');
+}
+
+sub _psgi_env {
+    my ($self, $c) = @_;
+
+    my $env = $c->req->env;
+
+    my $body = $c->req->build_body;
+    $env = {
+        %$env,
+        'psgi.input' => IO::Scalar->new(\$body),
+        'psgi.errors' => *STDERR,
+        REQUEST_METHOD => $c->req->method,
+        QUERY_STRING => $c->req->url->query->to_string,
+        SERVER_NAME => $c->req->url->to_abs->host,
+        SERVER_PORT => $c->req->url->to_abs->port,
+        SERVER_PROTOCOL => 'HTTP/1.1',
+        CONTENT_LENGTH => $c->req->headers->content_length,
+        CONTENT_TYPE => $c->req->headers->content_type,
+        REMOTE_ADDR => $c->tx->remote_address,
+        SCRIPT_NAME => $c->req->url->path->to_string,
+    };
+
+    # Starman sets PATH_INFO to the same value of SCRIPT_NAME, which confuses
+    # CGI and causes the redirect after OPAC login to fail
+    delete $env->{PATH_INFO} if ($env->{PATH_INFO} eq $env->{SCRIPT_NAME});
+
+    for my $name (@{ $c->req->headers->names }) {
+        my $value = $c->req->headers->header($name);
+        $name =~ s/-/_/g;
+        $name = 'HTTP_' . uc($name);
+        $env->{$name} = $value;
+    }
+
+    return $env;
+}
+
+1;

Koha/App/Plugin/RESTV1.pm

@@ -0,0 +1,32 @@
+package Koha::App::Plugin::RESTV1;
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Mojo::Base 'Mojolicious::Plugin';
+
+use Koha::REST::V1;
+
+sub register {
+    my ($self, $app) = @_;
+
+    $app->routes->any('/api')->detour(app => Koha::REST::V1->new);
+}
+
+1;

app.psgi

@@ -0,0 +1,52 @@
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use FindBin;
+use Plack::Builder;
+use Mojo::Server::PSGI;
+
+sub psgi_app {
+    my ($script) = @_;
+
+    my $server = Mojo::Server::PSGI->new;
+    $server->load_app("$FindBin::Bin/$script");
+
+    return $server->to_psgi_app;
+}
+
+my $opac = psgi_app('bin/opac');
+my $intranet = psgi_app('bin/intranet');
+
+my $opac_port = $ENV{KOHA_OPAC_PORT} || 5001;
+my $intranet_port = $ENV{KOHA_INTRANET_PORT} || 5000;
+my $port2app = {
+    $opac_port => $opac,
+    $intranet_port => $intranet,
+};
+
+builder {
+    enable 'ReverseProxy';
+    enable '+Koha::Middleware::SetEnv';
+    enable '+Koha::Middleware::RealIP';
+    sub {
+        my $env = shift;
+        my $app = $port2app->{$env->{SERVER_PORT}} || $intranet;
+        $app->($env);
+    };
+}

bin/intranet

@@ -0,0 +1,43 @@
+#!/usr/bin/env perl
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use FindBin;
+use lib "$FindBin::Bin/..";
+
+use Mojolicious::Commands;
+
+Mojolicious::Commands->start_app('Koha::App::Intranet');

bin/opac

@@ -0,0 +1,27 @@
+#!/usr/bin/env perl
+
+# Copyright 2020 BibLibre
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use FindBin;
+use lib "$FindBin::Bin/..";
+
+use Mojolicious::Commands;
+
+Mojolicious::Commands->start_app('Koha::App::Opac');

etc/nginx.conf

@@ -0,0 +1,33 @@
+# This config file assume you are using starman with the app.psgi that can be
+# found in the root directory of Koha, and that it listens on ports 5000-5001
+
+upstream intranet {
+    server 127.0.0.1:5000;
+}
+upstream opac {
+    server 127.0.0.1:5001;
+}
+
+server {
+    listen 80;
+    listen [::]:80;
+
+    server_name intranet.koha-dev; # CHANGEME
+
+    location / {
+        include proxy_params;
+        proxy_pass http://intranet;
+    }
+}
+
+server {
+    listen 80;
+    listen [::]:80;
+
+    server_name opac.koha-dev; # CHANGEME
+
+    location / {
+        include proxy_params;
+        proxy_pass http://opac;
+    }
+}