Refactored app callbacks

app.py

@@ -1,4 +1,4 @@
-from typing import Tuple
+from typing import Dict, Iterable, List, Tuple
 import dash
 import dash_core_components as dcc
 import dash_html_components as html
@@ -20,7 +20,10 @@
 DPH_CASE_COLS = 'cases_{}day', 'case_{}day_rate', 'adj_case_{}day_rate'
 
 LOS_ANGELES = 'Los Angeles'
-YAXIS_RANGE = 400, 1000, 1600
+YAXIS_RANGE = 300, 600, 1000, 1600
+
+LABEL = 'label'
+VALUE = 'value'
 
 # First Known COVID-19 Case in California
 ABSOLUTE_FIRST_DAY = pd.to_datetime('2020-01-26')
@@ -52,6 +55,10 @@ def latimes_county_places(county: str) -> Tuple[str, ...]:
  return tuple(places)
 
 
+def create_dash_options(iterable: Iterable) -> List[Dict[str, str]]:
+ return [{LABEL: x, VALUE: x} for x in iterable]
+
+
 def place_to_id(county, name):
  id_ = df_times.loc[(df_times[COUNTY] == county) & (df_times[NAME] == name),
  ID].unique()
@@ -82,9 +89,6 @@ def id_to_place(county, id_):
 GitHub: [amhirsch/ca-local-covid19-dashboard](https://github.com/amhirsch/ca-local-covid19-dashboard)
 '''
 
-LABEL = 'label'
-VALUE = 'value'
-
 CONTROLS = html.Div([
  html.Label('County', htmlFor='selected-county'),
  html.Div([
@@ -158,44 +162,41 @@ def id_to_place(county, id_):
  })
 
 
-@app.callback(Output('selected-place-label', 'children'),
- Output('selected-place-value', 'options'),
- Output('selected-place-value', 'value'),
+@app.callback(Output('selected-data-source', 'options'),
  Output('selected-data-source', 'value'),
- Input('selected-county', 'value'),
- Input('selected-place-value', 'value'),
- Input('selected-data-source', 'value'))
-def county_places(county, place_or_id, data_source):
- places = (LACDPH_CSA_LIST
- if data_source == LACDPH else latimes_county_places(county))
+ Input('selected-county', 'value'))
+def county_data_options(county):
+ data_src_options = [{LABEL: 'Los Angeles Times', VALUE: LATIMES}]
  if county == LOS_ANGELES:
- if place_or_id in places:
- selected = place_or_id
- elif data_source == LACDPH and place_or_id in latimes_county_places(
- LOS_ANGELES):
- selected = place_to_id(LOS_ANGELES, place_or_id)
- elif data_source == LATIMES and place_or_id in LACDPH_CSA_LIST:
- selected = id_to_place(LOS_ANGELES, place_or_id)
- else:
- selected = places[0]
- else:
- selected = place_or_id if place_or_id in places else places[0]
+ data_src_options.append({LABEL: 'LACDPH', VALUE: LACDPH})
+ return data_src_options, LATIMES
 
- return ('Place'
- if data_source == LATIMES else 'Countywide Statistical Area', [{
- LABEL: x,
- VALUE: x
- } for x in places], selected,
- data_source if county == LOS_ANGELES else LATIMES)
 
+@app.callback(Output('selected-place-label', 'children'),
+ Input('selected-data-source', 'value'))
+def place_label(data_src):
+ return 'Place' if data_src == LATIMES else 'Countywide Statistical Area'
 
-@app.callback(Output('selected-data-source', 'options'),
- Input('selected-county', 'value'))
-def data_source_options(county):
- options = [{LABEL: 'Los Angeles Times', VALUE: 'latimes'}]
- if county == LOS_ANGELES:
- options.append({LABEL: 'LACDPH', VALUE: LACDPH})
- return options
+
+@app.callback(Output('selected-place-value', 'options'),
+ Output('selected-place-value', 'value'),
+ Input('selected-county', 'value'),
+ Input('selected-data-source', 'value'),
+ Input('selected-place-value', 'value'))
+def place_value(county, data_src, orig_place):
+ if data_src == LACDPH:
+ place_options = LACDPH_CSA_LIST
+ if orig_place in latimes_county_places(LOS_ANGELES):
+ orig_place = place_to_id(LOS_ANGELES, orig_place)
+ else:
+ place_options = latimes_county_places(county)
+ if county == LOS_ANGELES and orig_place in LACDPH_CSA_LIST:
+ orig_place = id_to_place(LOS_ANGELES, orig_place)
+ if orig_place in place_options:
+ place_selection = orig_place
+ else:
+ place_selection = place_options[0]
+ return create_dash_options(place_options), place_selection
 
 
 @app.callback(Output('csa-ts', 'figure'), Input('selected-county', 'value'),