Add build step.

.github/workflows/build.yml

@@ -0,0 +1,48 @@
+name: Build
+
+on: push
+
+jobs:
+  checks:
+    name: Checks
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+      - name: Install python deps
+        run: pip install -r requirements.txt
+      - name: Install optional build tools
+        run: pip install pycodestyle pyflakes nose2
+      - name: Check flakes
+        run: pyflakes *.py
+      - name: Check style
+        run: pycodestyle *.py
+      - name: Check types
+        run: mypy *.py
+      - name: Run unit tests
+        run: nose2
+  pipeline:
+    name: Pipeline
+    runs-on: ubuntu-latest
+    needs: [checks]
+    if: github.ref == 'refs/heads/main'
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+      - name: Install python deps
+        run: pip install -r requirements.txt
+      - name: Run visualization
+        run: python draw_berkeley_bart.py berkeley_trips.csv berkeley_trips.png
+      - name: Upload result
+        uses: actions/upload-artifact@v3
+        with:
+          name: berkeley_trips
+          path: berkeley_trips.png

.gitignore

@@ -0,0 +1 @@
+__pycache__

README.md

@@ -33,7 +33,7 @@ To get this repository ready, let's execute a few tools that can help us check o
 
  - **pyflakes**: This is a check for clear issues like undefined variables. Execute with `pyflakes *.py`.
  - **nose2**: This is a unit test runner. Go ahead and give this a shot with `nose2` and notice that it looks like the test for the line length is failing. See if you can fix it!
- - **pycodestyle**: Execute checks for code style issues with `pycodestyle *.py`. Can you fix any of the ifnal issues?
+ - **pycodestyle**: Execute checks for code style issues with `pycodestyle *.py`. Can you fix any of the final issues? This is controlled by `setup.cfg`.
 
 We will next execute these from within CI. Note that we just did a little [test driven development](https://www.youtube.com/watch?v=B1j6k2j2eJg) where the test is written before the code.
 

draw_berkeley_bart.py

@@ -15,20 +15,22 @@
 USAGE_STR = 'USAGE: python draw_berkeley_bart.py input_loc output_loc'
 
 DEFAULT_DATA_LOCATION = 'berkeley_trips.csv'
-BG_COLOR = '#ECECEC'
+BG_COLOR = '#EAEAEA'
 FG_COLOR = '#333333'
 TICK_COLOR = '#FFFFFF'
 TITLE = 'Bart trips from Downtown Berkeley to other stations in March 2024.'
 WIDTH = 600
 HEIGHT = 600
+LINE_MIN_LEN = 70
+LINE_MAX_LEN = 210
 
 
 class Station:
     """Data record describing a single station."""
-    
+
     def __init__(self, name, code, count):
         """Create a new station record.
-        
+
         Args:
             name: The full name of the station.
             code: The short code name of the station.
@@ -37,26 +39,26 @@ def __init__(self, name, code, count):
         self._name = name
         self._code = code
         self._count = count
-    
+
     def get_name(self):
         """Get the human-readable name of the station.
-        
+
         Returns:
             Name of the station like "Downtown Berkeley" as provided by BART.
         """
         return self._name
-    
+
     def get_code(self):
         """Get the short code name of the station.
-        
+
         Returns:
             Two character codename for the station like BK.
         """
         return self._code
-    
+
     def get_count(self):
         """Get the number of trips that went from Berkeley to this station.
-        
+
         Returns:
             Number of trips to this station in the target month. This is the
             number of "tag outs" for journies which started at Downtown Bereley
@@ -67,35 +69,35 @@ def get_count(self):
 
 class DataFacade:
     """Object which simplifies access to ridership data."""
-    
+
     def __init__(self, sketch):
         """Create a new data facade.
-        
+
         Args:
             sketch: The sketch through which ridership data will be accessed.
         """
         self._sketch = sketch
-    
+
     def get_stations(self, loc):
         """Get a list of stations from the underlying data.
-        
+
         Args:
             loc: The location from which to parse the data.
-        
+
         Returns:
             List of stations from the underlying dataset sorted by total number
             of trips in ascending order.
         """
         raw_data = self._sketch.get_data_layer().get_csv('berkeley_trips.csv')
         parsed_data = map(lambda x: self._parse_data_point(x), raw_data)
         return sorted(parsed_data, key=lambda x: x.get_count())
-    
+
     def _parse_data_point(self, target):
         """Parse an input raw CSV row as a Station record.
-        
+
         Args:
             target: Dictionary representing a single row from the input dataset.
-        
+
         Returns:
             Station object representing the row after parsing.
         """
@@ -107,29 +109,29 @@ def _parse_data_point(self, target):
 
 class StationVizPresenter:
     """Presenter which runs the visualization."""
-    
+
     def __init__(self, sketch):
         """Create a presenter to run a bart visualization.
-        
+
         Args:
             sketch: The sketch to run.
         """
         self._sketch = sketch
-    
+
     def draw(self, records):
         """Draw the visualization.
-        
+
         Args:
             records: The stations to draw.
         """
         self._sketch.clear(BG_COLOR)
-        
+
         max_value = max(map(lambda x: x.get_count(), records))
-        
+
         self._draw_title()
         self._draw_axis(max_value)
         self._draw_data(max_value, records)
-    
+
     def _draw_title(self):
         """Draw the title at the bottom of the visual."""
         self._sketch.clear_stroke()
@@ -140,42 +142,42 @@ def _draw_title(self):
 
     def _draw_axis(self, max_value):
         """Draw the axis and other non-data chart elements.
-        
+
         Args:
             max_value: The maximum number of trips to a single station expected.
         """
         # We will change the coordinate system such that 300, 300 is 0, 0 and
         # push saves the original coordinate system state.
         self._sketch.push_transform()
-        
+
         # Move to the center of the visualization
         self._sketch.translate(WIDTH / 2, HEIGHT / 2)
-        
+
         # Setup some drawing preferences
         self._sketch.set_text_align('center', 'center')
         self._sketch.set_ellipse_mode('radius')
-        
+
         # Draw the Bereley text at the center
         self._sketch.clear_stroke()
         self._sketch.set_fill(FG_COLOR)
         self._sketch.set_text_font('PublicSans-Regular.otf', 20)
         self._sketch.draw_text(0, 0, 'Berkeley')
-        
+
         # Draw ticks
         self._sketch.set_text_font('PublicSans-Regular.otf', 10)
         for value in range(0, max_value + 5000, 5000):
             x = self._get_line_length(max_value, value)
-            
+
             # Draw a light reference line as a circle
             self._sketch.clear_fill()
             self._sketch.set_stroke(TICK_COLOR)
             self._sketch.draw_ellipse(0, 0, x, x)
-            
+
             # Draw number of trips as text
             self._sketch.clear_stroke()
             self._sketch.set_fill(FG_COLOR)
             self._sketch.draw_text(x, 0, f'{value:,}')
-        
+
         # Put the coordinate system back (restore the coordinate system state
         # we saved earlier with push_transform). This undoes the translate.
         self._sketch.pop_transform()
@@ -184,44 +186,44 @@ def _draw_data(self, max_value, records):
         # We will change the coordinate system such that 300, 300 is 0, 0 and
         # rotate. Push saves the original coordinate system state.
         self._sketch.push_transform()
-        
+
         # Move to the center of the visualization
         self._sketch.translate(WIDTH / 2, HEIGHT / 2)
-        
+
         # Set some drawing preferences
         self._sketch.set_angle_mode('degrees')
-        
+
         # Determine how much we have to space out stations
         num_lanes = len(records) + 1
-        
+
         # Draw each station
         for record in records:
             # Figure out how far from the center this station will be drawn.
             length = self._get_line_length(max_value, record.get_count())
-            
+
             # Rotate a little for each station
             self._sketch.rotate(360 / num_lanes)
-            
+
             # Draw a line from the center according to (length proportional to)
             # the number of trips to that station from Downtown Berkeley.
             self._sketch.clear_fill()
             self._sketch.set_stroke(FG_COLOR)
             self._sketch.draw_line(70, 0, length, 0)
-            
+
             # Draw the name of the station.
             self._sketch.clear_stroke()
             self._sketch.set_fill(FG_COLOR)
             self._sketch.set_text_font('PublicSans-Regular.otf', 10)
             self._sketch.set_text_align('left', 'center')
             self._sketch.draw_text(length + 2, 0, record.get_name())
-        
+
         # Put the coordinate system back (restore the coordinate system state
         # we saved earlier with push_transform). This undoes the translate and
         # rotate.
         self._sketch.pop_transform()
-    
+
     def _get_line_length(self, max_value, count):
-        return 140 / max_value * count + 70
+        return (LINE_MAX_LEN - LINE_MIN_LEN) / max_value * count + LINE_MIN_LEN
 
 
 def main():
@@ -237,16 +239,16 @@ def main():
     else:
         print(USAGE_STR)
         sys.exit(1)
-    
+
     # Create a sketch and initalize the data facade (model) and presenter.
     sketch = sketchingpy.Sketch2D(WIDTH, HEIGHT)
     data_facade = DataFacade(sketch)
     presenter = StationVizPresenter(sketch)
-    
+
     # Get the data and draw
     data = data_facade.get_stations(data_loc)
     sketch.on_step(lambda x: presenter.draw(data))
-    
+
     # If running interactive, show the visualization. Otherwise write to disk
     # at location specified.
     if interactive:

setup.cfg

@@ -0,0 +1,3 @@
+[pycodestyle]
+max-line-length = 100
+ignore = E125,E128,E502,E731,E722,E402

test_draw_berkeley_bart.py

@@ -0,0 +1,40 @@
+"""Unit tests for the BART Berkeley trips visualization.
+
+License: BSD
+"""
+
+import unittest
+
+import sketchingpy
+
+import draw_berkeley_bart
+
+
+class BerkeleyBartTests(unittest.TestCase):
+
+    def setUp(self):
+        self._sketch = sketchingpy.Sketch2D(500, 500)
+
+    def test_parse_data_point(self):
+        data_facade = draw_berkeley_bart.DataFacade(self._sketch)
+        result = data_facade._parse_data_point({
+            'name': 'test',
+            'code': 'te',
+            'count': '1,234'
+        })
+        self.assertEqual(result.get_name(), 'test')
+        self.assertEqual(result.get_code(), 'te')
+        self.assertEqual(result.get_count(), 1234)
+
+    def test_get_line_length_zero(self):
+        presenter = draw_berkeley_bart.StationVizPresenter(self._sketch)
+        self.assertEqual(presenter._get_line_length(100, 0), draw_berkeley_bart.LINE_MIN_LEN)
+
+    def test_get_line_length_max(self):
+        presenter = draw_berkeley_bart.StationVizPresenter(self._sketch)
+        self.assertEqual(presenter._get_line_length(100, 100), draw_berkeley_bart.LINE_MAX_LEN)
+
+    def test_get_line_length_half(self):
+        presenter = draw_berkeley_bart.StationVizPresenter(self._sketch)
+        halfway = (draw_berkeley_bart.LINE_MAX_LEN + draw_berkeley_bart.LINE_MIN_LEN) / 2
+        self.assertEqual(presenter._get_line_length(100, 50), halfway)