Adiciona leitura de layout a partir de yaml

crispy_layout_mixin.py

@@ -1,3 +1,6 @@
+from math import ceil
+
+import rtyaml
 from crispy_forms.bootstrap import FormActions
 from crispy_forms.helper import FormHelper
 from crispy_forms.layout import HTML, Div, Fieldset, Layout, Submit
@@ -99,3 +102,30 @@ class CrispyLayoutFormMixin(object):
                        for fieldname, span in row]
                       for row in rows]
              } for legend, *rows in self.layout]
+
+
+# TODO cache this
+def read_yaml_from_file(filename):
+    with open(filename, 'r') as yamlfile:
+        return rtyaml.load(yamlfile)
+
+
+def read_layout_from_yaml(filename, key):
+    # TODO cache this
+    yaml = read_yaml_from_file(filename)
+    base = yaml[key]
+
+    def line_to_namespans(line):
+        split = [cell.split(':') for cell in line.split()]
+        namespans = [[s[0], int(s[1]) if len(s) > 1 else 0] for s in split]
+        remaining = 12 - sum(s for n, s in namespans)
+        nondefined = [ns for ns in namespans if not ns[1]]
+        while nondefined:
+            span = ceil(remaining / len(nondefined))
+            namespan = nondefined.pop(0)
+            namespan[1] = span
+            remaining = remaining - span
+        return list(map(tuple, namespans))
+
+    return [(legend, [line_to_namespans(l) for l in lines])
+            for legend, lines in base.items()]

requirements/requirements.txt

@@ -15,4 +15,5 @@ libsass
 psycopg2
 pytz
 pyyaml
+rtyaml
 unipath

test_crispy_layout_mixin.py

@@ -0,0 +1,29 @@
+from crispy_layout_mixin import read_layout_from_yaml
+
+
+def test_read_layout_from_yaml(tmpdir):
+
+    contents = '''
+ModelName:
+  Cool Legend:
+  - name:9  place  tiny
+  - field  nature:2
+  - kind:1  date  unit:5 status
+  More data:
+  - equalA  equalB  equalC
+  - highlander '''
+    file = tmpdir.join('zzz.yaml')
+    file.write(contents)
+
+    expected = [
+        ('Cool Legend', [
+            [('name', 9),  ('place', 2), ('tiny', 1)],
+            [('field', 10), ('nature', 2)],
+            [('kind', 1), ('date', 3), ('unit', 5), ('status', 3)],
+        ]),
+        ('More data', [
+            [('equalA', 4), ('equalB', 4), ('equalC', 4)],
+            [('highlander', 12)],
+        ]),
+    ]
+    assert read_layout_from_yaml(file.strpath, 'ModelName') == expected