Refactor datastores to classes (#9179)

* Datastores to object oriented code, using the Laravel IoC container

Change instantiation
better DI
move OpenTSDB

Small re-orgs

remove unused stuff

Fix graphs and other scripts

Use DI for all except rrd

fix up connection error handling

Add tests, fix up a "few" things
Add Config::forget()

Style fixes

Don't reference legacy code

remove accidental code paste

Add datastores phpunit groups

some tests

* rebase fixes

* some test fixes

* shorter tests

* shorter tests

* Don't except when rrdtool can't be started.

* restore tests

* fix rrd tests

* fix iterable change upstream

* fix isValidDataset

* fix invalid data bug

* fix mysql incorrect ds

* fix issue with data that is too long

* use regular data_update()

* Use log facade

* OpenTSDB mis-ordered arguments fix

* Making a singleton with different options makes different singletons.  Just use the global config settings to disable datastores.

* only filter tags for datastores that won't it don't modify the tags permanently

* Update copyrights to include original authors.

* Stats for all datastores

* Fix mysql sends different rrd / other ds names

* fix snmp last stats not initialized
remove unused function

* remove unused function and move single use function closer to its use

* InfluxDB does not need to update null or U values.
Skip write if all fields are empty

* Fix smart value checks

* fix style issues

LibreNMS/Interfaces/Data/Datastore.php

@@ -0,0 +1,74 @@
+<?php
+/**
+ * Datastore.php
+ *
+ * Interface for datastores. Will be used to send them data through the put() method
+ *
+ * This program 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.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @package    LibreNMS
+ * @link       http://librenms.org
+ * @copyright  2018 Tony Murray
+ * @author     Tony Murray <murraytony@gmail.com>
+ */
+
+namespace LibreNMS\Interfaces\Data;
+
+interface Datastore
+{
+    /**
+     * Check if this is enabled by the configuration
+     *
+     * @return boolean
+     */
+    public static function isEnabled();
+
+    /**
+     * Checks if the datastore wants rrdtags to be sent when issuing put()
+     *
+     * @return boolean
+     */
+    public function wantsRrdTags();
+
+    /**
+     * The name of this datastore
+     *
+     * @return string
+     */
+    public function getName();
+
+    /**
+     * Array of stats should be [type => [count => n, time => s]]
+     *
+     * @return array
+     */
+    public function getStats();
+
+    /**
+     * Datastore-independent function which should be used for all polled metrics.
+     *
+     * RRD Tags:
+     *   rrd_def     RrdDefinition
+     *   rrd_name    array|string: the rrd filename, will be processed with rrd_name()
+     *   rrd_oldname array|string: old rrd filename to rename, will be processed with rrd_name()
+     *   rrd_step             int: rrd step, defaults to 300
+     *
+     * @param array $device
+     * @param string $measurement Name of this measurement
+     * @param array $tags tags for the data (or to control rrdtool)
+     * @param array|mixed $fields The data to update in an associative array, the order must be consistent with rrd_def,
+     *                            single values are allowed and will be paired with $measurement
+     */
+    public function put($device, $measurement, $tags, $fields);
+}