Add API endpoint to get service graphs (#15138)

* Add API endpoint to get service graphs

* Docs: Add missing title to get_graph_by_service

doc/API/Devices.md

@@ -564,6 +564,38 @@ Output:
 
 Output is an image.
 
+### `get_graph_by_service`
+
+Get the graph for a service
+
+Route: `/api/v0/devices/:hostname/services/:service_id/graphs/:datasource`
+
+- hostname can be either the device hostname or id
+- service id
+- datasource is the name of the service datasource
+
+Input:
+
+- from: This is the date you would like the graph to start - See
+  [http://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html](http://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html)
+  for more information.
+- to: This is the date you would like the graph to end - See
+  [http://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html](http://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html)
+  for more information.
+- width: The graph width, defaults to 1075.
+- height: The graph height, defaults to 300.
+
+  Example:
+
+```curl
+curl -H 'X-Auth-Token: YOURAPITOKENHERE' https://librenms.org/api/v0/services/localhost/35/graphs/loss
+```
+
+Output:
+
+Output is an image.
+
+
 ### `get_port_graphs`
 
 Get a list of ports for a particular device.

includes/html/api_functions.inc.php

@@ -248,6 +248,24 @@ function get_graph_generic_by_hostname(Request $request)
     });
 }
 
+function get_graph_by_service(Request $request)
+{
+    $vars = [];
+    $vars['id'] = $request->route('id');
+    $vars['type'] = 'service_graph';
+    $vars['ds'] = $request->route('datasource');
+
+    $hostname = $request->route('hostname');
+    // use hostname as device_id if it's all digits
+    $device_id = ctype_digit($hostname) ? $hostname : getidbyname($hostname);
+    $device = device_by_id_cache($device_id);
+    $vars['device'] = $device['device_id'];
+
+    return check_device_permission($device_id, function () use ($request, $vars) {
+        return api_get_graph($request, $vars);
+    });
+}
+
 function list_locations()
 {
     $locations = dbFetchRows('SELECT `locations`.* FROM `locations` WHERE `locations`.`location` IS NOT NULL');

routes/api.php

@@ -119,6 +119,7 @@ Route::prefix('v0')->namespace('\App\Api\Controllers')->group(function () {
         // consumes the route below, but passes to it when detected
         Route::get('{hostname}/ports/{ifname}', 'LegacyApiController@get_port_stats_by_port_hostname')->name('get_port_stats_by_port_hostname')->where('ifname', '.*');
         Route::get('{hostname}/ports/{ifname}/{type}', 'LegacyApiController@get_graph_by_port_hostname')->name('get_graph_by_port_hostname');
+        Route::get('{hostname}/services/{id}/graphs/{datasource}', 'LegacyApiController@get_graph_by_service')->name('get_graph_by_service');
 
         Route::get('{hostname}/{type}', 'LegacyApiController@get_graph_generic_by_hostname')->name('get_graph_generic_by_hostname');
         Route::get('', 'LegacyApiController@list_devices')->name('list_devices');