sample_set.py, sample_set/custom.html fix issues with helper instance

there were a couple issues with calls to in non-existant helper
instance, so now we have an instance to work with

server/web2py/applications/vidjil/controllers/sample_set.py

@@ -334,7 +334,11 @@ def custom():
         request.vars["custom_list"] = [request.vars["custom_list"]]
 
     myGroupBy = None
+    helper = None
     if request.vars["id"] and auth.can_view_sample_set(request.vars["id"]):
+        sample_set = db.sample_set[request.vars["id"]]
+        factory = ModelFactory()
+        helper = factory.get_instance(type=sample_set.sample_type)
         q = ((auth.vidjil_accessible_query(PermissionEnum.read_config.value, db.config))
                 & (db.sample_set.id == request.vars["id"])
                 & (db.sample_set_membership.sample_set_id == db.sample_set.id)
@@ -403,7 +407,8 @@ def custom():
 
     return dict(query=query,
                 config_id=config_id,
-                config=config)
+                config=config,
+                helper=helper)
 
 def confirm():
     if auth.can_modify_sample_set(request.vars["id"]):

server/web2py/applications/vidjil/views/sample_set/custom.html

@@ -6,7 +6,7 @@
 <div>
 
 	{{ if request.vars['id']: }}
-		<h3>Compare samples from {{=helper.get_type_display()}} {{=helper.get_name(request.vars['id'])}}</h3>
+		<h3>Compare samples from {{=helper.get_type_display()}} {{=get_sample_name(request.vars["id"])}}</h3>
 	{{ else: }}
 	        <h3>Compare samples</h3>
     {{pass}}
@@ -50,7 +50,7 @@ <h3>Compare samples</h3>
     <table class="db_table table_compare" id="table">
         <thead>
             <tr><td class="column5"> </td>
-                <td class="column_200"> {{=helper.get_type_display()}} </td>
+                <td class="column_200"> {{=helper.get_type_display() if helper is not None else "name"}} </td>
                 <td class="column_200"> file name </td>
                 <td class="column_100"> sampling date </td>
                 <td> info </td>