Simplify processing input file sections

src/yaml2wireviz.py

@@ -47,43 +47,33 @@ with open(filename, 'r') as stream:
         print(exc)
 
 h = wireviz.Harness()
-# add nodes
-if 'nodes' in input and type(input['nodes']) == dict:
-    if len(input['nodes']) > 0:
-        for k, o in input['nodes'].items():
+
+# add items
+sections = ['nodes','wires','ferrules','connections']
+types    = [dict, dict, dict, list]
+for sec, ty in zip(sections, types):
+    if sec in input and type(input[sec]) == ty:
+        if len(input[sec]) > 0:
+            if ty == dict:
+                for k, o in input[sec].items():
+                    if sec == 'nodes':
                         h.add_node(name=k, **o)
-    else:
-        print('Node list empty')
-else:
-    print('No node list found')
-    input['nodes'] = {}
-
-# add wires
-if 'wires' in input and type(input['wires']) == dict:
-    if len(input['wires']) > 0:
-        for k, o in input['wires'].items():
+                    elif sec == 'wires':
                         h.add_cable(name=k, **o)
-    else:
-        print('Wire list empty')
-else:
-    print('No wire list found')
-    input['wires'] = {}
-
-if 'ferrules' in input and type(input['ferrules']) == dict:
-    if len(input['wires']) > 0:
+                    elif sec == 'ferrules':
                         pass
         else:
-        print('Ferrule list empty')
+            print('{} section empty'.format(sec))
     else:
-    print('No ferrule list found')
-    input['ferrules'] = {}
+        print('No {} section found'.format(sec))
+        if ty == dict:
+            input[sec] = {}
+        elif ty == list:
+            input[sec] = []
 
 # add connections
-if 'connections' in input:
-    if len(input['connections']) > 0:
 ferrule_counter = 0
-        conlist = input['connections']
-        for con in conlist:
+for con in input['connections']:
     if len(con) == 3: # format: connector -- wire -- conector
 
         for c in con:
@@ -188,10 +178,5 @@ if 'connections' in input:
 
     else:
         raise Exception('Wrong number of connection parameters')
-    else:
-        print('Connection list empty')
-else:
-    print('No connection list found')
-    input['connections'] = {}
 
 h.output(filename='output', format=('png','svg'), view=False)