preshared_key is a per-peer option

this commit also handles removal of preshared keys. Fixes #5.

_states/wireguard.py

     return False
 
 
-def present(name, listen_port=None, fwmark=None, private_key=None,
-        preshared_key=None):
+def present(name, listen_port=None, fwmark=None, private_key=None):
     """
     Make sure a wireguard interface exists.
     """
         __salt__['wg.set'](name, private_key=private_key)
         ret['changes']['private key'] = 'private key changed.'
 
-    if show.get('preshared key') != preshared_key:
-        __salt__['wg.set'](name, preshared_key=preshared_key)
-        ret['changes']['preshared key'] = 'preshared key changed.'
-
     ret['result'] = True
 
     return ret
 
 
 def peer_present(name, interface, endpoint=None, persistent_keepalive=None,
-                 allowed_ips=None):
+                 allowed_ips=None, preshared_key=None):
     ret = dict(name=name, changes=dict(), result=False, comment=None)
 
     show = __salt__['wg.show'](interface)
     if not show:
         __salt__['wg.set'](interface, peer=name, endpoint=endpoint,
                 persistent_keepalive=persistent_keepalive,
-                allowed_ips=','.join(allowed_ips))
+                allowed_ips=','.join(allowed_ips), preshared_key=preshared_key)
         ret['changes'][name] = 'Peer created.'
         ret['result'] = True
         return ret
     if sorted(show.get('allowed ips')) != sorted(allowed_ips):
         __salt__['wg.set'](interface, peer=name, allowed_ips=','.join(allowed_ips))
         ret['changes']['allowed ips'] = dict(new=allowed_ips, old=show.get('allowed ips'))
+    if show.get('preshared key') and preshared_key and show.get('preshared key') != preshared_key:
+        __salt__['wg.set'](interface, peer=name, preshared_key=preshared_key)
+        ret['changes']['preshared key'] = 'preshared key changed.'
+    if show.get('preshared key') and not preshared_key:
+        __salt__['wg.set'](interface, peer=name, preshared_key='')
+        ret['changes']['preshared key'] = 'preshared key deleted.'
+
 
 
     ret['result'] = True

pillar.example

       listen_port: 51820
       # fwmark: 0x1
       private_key: secret
-      # preshared_key: secret
       peers:
         - peer: 1ymBfBty05PNhD/QJKUlu4aL2p4jKSWVVqVQWIQG6wM=
 	  # the note: will not go into wireguard configuration
             - 10.0.0.2/32
             - 'fdff::2/128'
           persistent_keepalive: 25
+          # preshared_key: secret
         - peer: 2ymBfBty05PNhD/QJKUlu4aL2p4jKSWVVqVQWIQG6wM=
           endpoint: '[2001:db8::1]:1339'
           allowed_ips:

wireguard/init.sls

   wg.present:
     - name: {{ interface }}
 {% for k, v in values.items() %}
-{% if k in ['listen_port', 'fwmark', 'private_key', 'preshared_key'] %}
+{% if k in ['listen_port', 'fwmark', 'private_key'] %}
     - {{k}}: {{v}}
 {% endif %}
 {% endfor %} {# values.items() #}
 {% for subnet in peer.get('allowed_ips', []) %}
       - {{subnet}}
 {% endfor %}
+{% if peer.get('preshared_key') != None %}
+    - preshared_key: {{ peer.get('preshared_key') }}
+{% endif %}
 {% endif %}
 {% endfor %}