first commit

lib/classes/aws/admin_settings_aws_region.php

@@ -0,0 +1,77 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Admin setting for AWS regions.
+ *
+ * @package    core
+ * @author     Dmitrii Metelkin <dmitriim@catalyst-au.net>
+ * @copyright  2020 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\aws;
+
+defined('MOODLE_INTERNAL') || die();
+
+require_once($CFG->dirroot . '/lib/adminlib.php');
+
+/**
+ * Admin setting for a list of AWS regions.
+ *
+ * @package    core
+ * @copyright  2020 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class admin_settings_aws_region extends \admin_setting_configtext {
+
+    /**
+     * Return part of form with setting.
+     *
+     * @param mixed $data array or string depending on setting
+     * @param string $query
+     * @return string
+     */
+    public function output_html($data, $query='') {
+        global $CFG, $OUTPUT;
+
+        $default = $this->get_defaultsetting();
+        $options = [];
+        // We do require() not require_once() here, as the file returns a value and we may need to get
+        // this value more than once.
+        $all = require($CFG->dirroot . '/lib/aws-sdk/src/data/endpoints.json.php');
+        $ends = $all['partitions'][0]['regions'];
+        if ($ends) {
+            foreach ($ends as $key => $value) {
+                $options[] = [
+                    'value' => $key,
+                    'label' => $key . ' - ' . $value['description'],
+                ];
+            }
+        }
+
+        $context = [
+            'list' => $this->get_full_name(),
+            'name' => $this->get_full_name(),
+            'id' => $this->get_id(),
+            'value' => $data,
+            'size' => $this->size,
+            'options' => $options,
+        ];
+        $element = $OUTPUT->render_from_template('core/aws/setting_aws_region', $context);
+        return format_admin_setting($this, $this->visiblename, $element, $this->description, true, '', $default, $query);
+    }
+}

lib/classes/aws/aws_helper.php

@@ -0,0 +1,100 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * AWS helper class. Contains useful functions when interacting with the SDK.
+ *
+ * @package    core
+ * @author     Peter Burnett <peterburnett@catalyst-au.net>
+ * @copyright  2020 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\aws;
+
+use Aws\CommandInterface;
+use Aws\AwsClient;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * This class contains functions that help plugins to interact with the AWS SDK.
+ *
+ * @copyright  2020 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class aws_helper {
+
+    /**
+     * This creates a proxy string suitable for use with the AWS SDK.
+     *
+     * @return string the string to use for proxy settings.
+     */
+    public static function get_proxy_string(): string {
+        global $CFG;
+        $proxy = '';
+        if (empty($CFG->proxytype)) {
+            return $proxy;
+        }
+        if ($CFG->proxytype === 'SOCKS5') {
+            // If it is a SOCKS proxy, append the protocol info.
+            $protocol = 'socks5://';
+        } else {
+            $protocol = '';
+        }
+        if (!empty($CFG->proxyhost)) {
+            $proxy = $CFG->proxyhost;
+            if (!empty($CFG->proxyport)) {
+                $proxy .= ':'. $CFG->proxyport;
+            }
+            if (!empty($CFG->proxyuser) && !empty($CFG->proxypassword)) {
+                $proxy = $protocol . $CFG->proxyuser . ':' . $CFG->proxypassword . '@' . $proxy;
+            }
+        }
+        return $proxy;
+    }
+
+    /**
+     * Configure the provided AWS client to route traffic via the moodle proxy for any hosts not excluded.
+     *
+     * @param AwsClient $client
+     * @return AwsClient
+     */
+    public static function configure_client_proxy(AwsClient $client): AwsClient {
+        $client->getHandlerList()->appendBuild(self::add_proxy_when_required(), 'proxy_bypass');
+        return $client;
+    }
+
+    /**
+     * Generate a middleware higher order function to wrap the handler and append proxy configuration based on target.
+     *
+     * @return callable Middleware high order callable.
+     */
+    protected static function add_proxy_when_required(): callable {
+        return function (callable $fn) {
+            return function (CommandInterface $command, ?RequestInterface $request = null) use ($fn) {
+                if (isset($request)) {
+                    $target = (string) $request->getUri();
+                    if (!is_proxybypass($target)) {
+                        $command['@http']['proxy'] = self::get_proxy_string();
+                    }
+                }
+
+                $promise = $fn($command, $request);
+                return $promise;
+            };
+        };
+    }
+}

lib/classes/aws/client_factory.php

@@ -0,0 +1,62 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * AWS Client factory. Retrieves a client with moodle specific HTTP configuration.
+ *
+ * @package    core
+ * @author     Peter Burnett <peterburnett@catalyst-au.net>
+ * @copyright  2022 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\aws;
+use Aws\AwsClient;
+
+/**
+ * AWS Client factory. Retrieves a client with moodle specific HTTP configuration.
+ *
+ * @copyright  2022 Catalyst IT
+ * @author     Peter Burnett <peterburnett@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class client_factory {
+    /**
+     * Get an AWS client with moodle specific HTTP configuration.
+     *
+     * @param string $class Fully qualified AWS classname e.g. \Aws\S3\S3Client
+     * @param array $opts array of constructor options for AWS Client.
+     * @return AwsClient
+     */
+    public static function get_client(string $class, array $opts): AwsClient {
+        // Modify the opts to add HTTP timeouts.
+        if (empty($opts['http'])) {
+            $opts['http'] = ['connect_timeout' => HOURSECS];
+        } else if (!array_key_exists('connect_timeout', $opts['http'])) {
+            // Try not to override existing settings.
+            $opts['http']['connect_timeout'] = HOURSECS;
+        }
+
+        // Blindly trust the call here. If it exceptions, the raw message is the most useful.
+        $client = new $class($opts);
+        if (!$client instanceof \Aws\AwsClient) {
+            throw new \moodle_exception('clientnotfound', 'factor_sms');
+        }
+
+        // Now we can configure the proxy with the routing aware middleware.
+        return aws_helper::configure_client_proxy($client);
+    }
+}