can update etcd with device id

syncthing_monitor/__main__.py

@@ -1,9 +1,9 @@
 from syncthing_monitor.config_xml import parse_api_key, set_listen_ip_to_any
+from syncthing_monitor.etcd_cluster_info import append_device_id
 from syncthing_monitor.syncthing_rest import get_device_id
 
 
 def loop(gui_port="8384", host="sync"):
-
     api_key = parse_api_key()
     print("Found API Key: {0}".format(api_key))
 
@@ -12,6 +12,8 @@ def loop(gui_port="8384", host="sync"):
     device_id = get_device_id(host, gui_port, api_key)
     print("Found Device ID: {0}".format(device_id))
 
+    append_device_id(device_id, 'etcd')
+
 
 if __name__ == "__main__":
     loop()

syncthing_monitor/etcd_cluster_info.py

@@ -0,0 +1,25 @@
+import json
+
+import etcd3 as etcd3
+from retrying import retry
+
+CLUSTER_INFO_KEY = '/syncthing_monitor/cluster_info'
+
+
+@retry
+def append_device_id(device_id, host, port=2379):
+    cluster_info = {'devices': []}
+
+    etcd = etcd3.client(host=host, port=port)
+
+    with etcd.lock('syncthing_monitor'):
+        raw_value = etcd.get(CLUSTER_INFO_KEY)[0]
+
+        if raw_value is not None:
+            cluster_info = json.loads(raw_value)
+
+        if not any(device_id in element for element in cluster_info['devices']):
+            cluster_info['devices'].append(device_id)
+
+        print("Updating etcd value for '{0}': {1}".format(CLUSTER_INFO_KEY, json.dumps(cluster_info)), flush=True)
+        etcd.put(CLUSTER_INFO_KEY, json.dumps(cluster_info))