Merge pull request #797 from dastels/uv-index

Add PyPortal UV Index display code

Author: makermelissa

PyPortal_UV_Index/code.py

@@ -0,0 +1,123 @@
+"""
+PyPortal UV Index display
+
+Adafruit invests time and resources providing this open source code.
+Please support Adafruit and open source hardware by purchasing
+products from Adafruit!
+
+Written by Dave Astels for Adafruit Industries
+Copyright (c) 2019 Adafruit Industries
+Licensed under the MIT license.
+
+All text above must be included in any redistribution.
+"""
+
+import time
+import json
+import board
+import displayio
+from adafruit_pyportal import PyPortal
+from adafruit_display_shapes.rect import Rect
+from adafruit_display_text.Label import Label
+from adafruit_bitmap_font import bitmap_font
+
+try:
+    from secrets import secrets
+except ImportError:
+    print("""WiFi settings are kept in secrets.py, please add them there!
+the secrets dictionary must contain 'ssid' and 'password' at a minimum""")
+    raise
+
+MAX_BAR_HEIGHT = 160
+MARGIN = 10
+SPACE_BETWEEN_BARS = 1
+
+COLORS = [0x00FF00, 0x83C602, 0xa2CF02,
+          0xF7DE03, 0xF6B502, 0xF78802,
+          0xF65201, 0xEA2709,
+          0xDA0115, 0xFC019E, 0xB548FF,
+          0x988FFE, 0x7EA7FE, 0x66BFFD, 0x4BD9FF]
+
+cwd = ("/"+__file__).rsplit('/', 1)[0]
+
+CAPTION_FONT_FILE = cwd+'/fonts/Helvetica-Bold-16.bdf'
+BAR_FONT_FILE = cwd+'/fonts/Arial-Bold-12.bdf'
+
+#pylint:disable=line-too-long
+url = 'https://enviro.epa.gov/enviro/efservice/getEnvirofactsUVHOURLY/ZIP/{0}/JSON'.format(secrets['zip'])
+#pylint:enable=line-too-long
+
+def extract_hour(date_time):
+    """Extract the hour in a format to use for display:
+    :param date_time: the timestamp from EPA UV readings
+    """
+    split_date_time = date_time.split()
+    hour = split_date_time[1]
+    suffix = split_date_time[2]
+    if hour[0] == '0':
+        hour = hour[1]
+    return '\n'.join([hour, suffix])
+
+def extract_date(date_time):
+    """Extract the date in a format to use for display:
+    :param date_time: the timestamp from EPA UV readings
+    """
+    return ' '.join(date_time.split('/')[0:2])
+
+pyportal = PyPortal(url=url,
+                    status_neopixel=board.NEOPIXEL,
+                    default_bg=0xFFFFFF,
+                    caption_font=CAPTION_FONT_FILE)
+
+canvas = displayio.Group(max_size=36)
+pyportal.splash.append(canvas)
+bar_font = bitmap_font.load_font(BAR_FONT_FILE)
+
+while True:
+    json_payload = ''
+    try:
+        json_payload = pyportal.fetch()
+        raw_data = json.loads(json_payload)
+    except (ValueError, RuntimeError) as ex:
+        print('Error: ', ex)
+        if isinstance(ex, ValueError):
+            print('JSON:', json_payload)
+        print('Retrying in 10 minutes')
+        time.sleep(600)
+        continue
+    data = []
+    for d in raw_data:
+        if d['UV_VALUE'] > 0:
+            entry = {}
+            entry['hour'] = extract_hour(d['DATE_TIME'])
+            entry['value'] = int(d['UV_VALUE'])
+            data.append(entry)
+    the_day = raw_data[0]['DATE_TIME']
+    pyportal.set_caption('UV Index for {0}'.format(extract_date(the_day)),
+                         (80, 20),
+                         0x000000)
+    number_of_readings = len(data)
+    whitespace = (number_of_readings - 1) * SPACE_BETWEEN_BARS + 2 * MARGIN
+    bar_width = (320 - whitespace) // number_of_readings
+    max_reading = max([d['value'] for d in data])
+
+    while len(canvas) > 0:
+        canvas.pop()
+
+    for i, reading in enumerate(data):
+        bar_height = (MAX_BAR_HEIGHT * reading['value']) // max_reading
+        x = int(MARGIN + i * (bar_width + SPACE_BETWEEN_BARS))
+        canvas.append(Rect(x, 200 - bar_height,
+                           bar_width, bar_height,
+                           fill=COLORS[reading['value']]))
+        canvas.append(Label(bar_font,
+                            x=x+3, y=220,
+                            text=reading['hour'],
+                            color=0x000000,
+                            line_spacing=0.6))
+        canvas.append(Label(bar_font,
+                            x=x+(bar_width//2)-4, y=208-bar_height,
+                            text=str(reading['value']),
+                            color=0x000000))
+
+    time.sleep(3600)                  #refresh hourly