Add Weather Underground destination

documentation/boards/enviro-weather.md

@@ -10,14 +10,22 @@ Enviro Weather is a super slimline all in one board for keeping a (weather) eye
 |---|---|---|---|---|
 |Temperature|`temperature`|celcius|°C|`22.11`|
 |Humidity|`humidity`|percent|%|`55.42`|
+|Dew Point|`dewpoint`|celcius|°C|`12.21`|
 |Air Pressure|`pressure`|hectopascals|hPa|`997.16`|
+|Adjusted Sea Level Air Pressure|`sea_level_pressure`|hectopascals|hPa|`1014.06`|
 |Luminance|`luminance`|lux|lx|`35`|
 |Rainfall|`rain`|millimetres|mm|`1.674`|
-|Rainfall Average|`rain_per_second`|millimetres per second|mm/s|`1.674`|
+|Rainfall Average Second|`rain_per_second`|millimetres per second|mm/s|`1.674`|
+|Rainfall Average Hour|`rain_per_hour`|millimetres per hour|mm/h|`1.674`|
+|Rainfall Today (local time)|`rain_today`|millimetres accumulated today|mm/s|`1.674`|
 |Wind Direction|`wind_direction`|angle|°|`45`|
 |Wind Speed|`wind_speed`|metres per second|m/s|`0.45`|
 |Voltage|`voltage`|volts|V|`4.035`|
 
+The rain today value is adjusted for DST in the UK by setting uk_bst = True in config.py
+For static time zone offsets (not taking account of DST), modify the utc_offset value in config.py
+The time zone offset value is ignored if uk_bst = True
+
 ## On-board devices
 
 - BME280 temperature, pressure, humidity sensor. [View datasheet](https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bme280-ds002.pdf)

documentation/destinations/wunderground.md

@@ -0,0 +1,30 @@
+# Weather Underground
+
+Referred to as "wunderground in config and code", Weather Underground is an online service provided by IBM for uploading and viewing information from personal Weather Stations (PWS) and provides general weather forecasts and news.
+
+You can sign up for a free account, configure a device and drop the credentials into the Enviro configuration to have the values appear on your own weather station dashboard that is also shared with the world.
+
+## Setting up a Weather Underground account and device
+
+1. Visit [Weather Underground](https://www.wunderground.com/)
+2. Create an account by clicking [Join](https://www.wunderground.com/signup) in the navigation bar
+3. Create your account using your email and a new password
+4. Browse to your [devices](https://www.wunderground.com/member/devices) in your profile
+5. Click Add New Device - Select "Raspberry Pi" as the device hardware and follow the wizard selecting appropriate values (if in doubt, go American units)
+6. Credentials are displayed on the summary screen, but you can check these at any time on the device page
+
+When you provision your device enter the station ID and station key and Enviro will automatically start sending data on the schedule you have requested.
+
+Ensure you have enabled the sea level pressure option and provided accurate [elevation data](https://whatismyelevation.com/) if you want to return pressure data.
+
+You can view the dashboard for your station by clicking the station name on the [devices](https://www.wunderground.com/member/devices) page.
+
+## Supported readings
+The following readings will be uploaded. Depending on board type, other readings may be collected, but not sent to Weather Underground and essentially dropped.
+- Temperature
+- Humidity
+- Sea level pressure
+- Wind speed
+- Wind direction
+
+There is potential to build logic to calculate rain per hour and convert luminance to solar radiation to capture all Enviro Weather sensor output, other boards may not be well suited to this destination.

enviro/boards/weather.py

@@ -1,9 +1,9 @@
-import time, math, os
+import time, math, os, config
 from breakout_bme280 import BreakoutBME280
 from breakout_ltr559 import BreakoutLTR559
 from machine import Pin, PWM
 from pimoroni import Analog
-from enviro import i2c, activity_led
+from enviro import i2c, activity_led, config
 import enviro.helpers as helpers
 from phew import logging
 from enviro.constants import WAKE_REASON_RTC_ALARM, WAKE_REASON_BUTTON_PRESS
@@ -25,6 +25,28 @@
 rain_pin = Pin(10, Pin.IN, Pin.PULL_DOWN)
 last_rain_trigger = False
 
+def log_rain():
+  # read the current rain entries
+  rain_entries = []
+  if helpers.file_exists("rain.txt"):
+    with open("rain.txt", "r") as rainfile:
+      rain_entries = rainfile.read().split("\n")
+
+  # add new entry
+  logging.info(f"> add new rain trigger at {helpers.datetime_string()}")
+  rain_entries.append(helpers.datetime_string())
+
+  # limit number of entries to 190 - each entry is 21 bytes including
+  # newline so this keeps the total rain.txt filesize just under one
+  # filesystem block (4096 bytes)
+  if len(rain_entries) > 190:
+    logging.info("Rain log file exceeded 190 entries and was truncated")
+    rain_entries = rain_entries[-190:]
+
+  # write out adjusted rain log
+  with open("rain.txt", "w") as rainfile:
+    rainfile.write("\n".join(rain_entries))
+
 def startup(reason):
   global last_rain_trigger
   import wakeup
@@ -33,24 +55,7 @@ def startup(reason):
   rain_sensor_trigger = wakeup.get_gpio_state() & (1 << 10)
 
   if rain_sensor_trigger:
-    # read the current rain entries
-    rain_entries = []
-    if helpers.file_exists("rain.txt"):
-      with open("rain.txt", "r") as rainfile:
-        rain_entries = rainfile.read().split("\n")
-
-    # add new entry
-    logging.info(f"> add new rain trigger at {helpers.datetime_string()}")
-    rain_entries.append(helpers.datetime_string())
-
-    # limit number of entries to 190 - each entry is 21 bytes including
-    # newline so this keeps the total rain.txt filesize just under one
-    # filesystem block (4096 bytes)
-    rain_entries = rain_entries[-190:]
-
-    # write out adjusted rain log
-    with open("rain.txt", "w") as rainfile:
-      rainfile.write("\n".join(rain_entries))
+    log_rain()
 
     last_rain_trigger = True
 
@@ -70,24 +75,7 @@ def check_trigger():
     time.sleep(0.05)
     activity_led(0)
 
-    # read the current rain entries
-    rain_entries = []
-    if helpers.file_exists("rain.txt"):
-      with open("rain.txt", "r") as rainfile:
-        rain_entries = rainfile.read().split("\n")
-
-    # add new entry
-    logging.info(f"> add new rain trigger at {helpers.datetime_string()}")
-    rain_entries.append(helpers.datetime_string())
-
-    # limit number of entries to 190 - each entry is 21 bytes including
-    # newline so this keeps the total rain.txt filesize just under one 
-    # filesystem block (4096 bytes)
-    rain_entries = rain_entries[-190:]
-
-    # write out adjusted rain log
-    with open("rain.txt", "w") as rainfile:
-      rainfile.write("\n".join(rain_entries))
+    log_rain()
 
   last_rain_trigger = rain_sensor_trigger
 
@@ -159,26 +147,65 @@ def wind_direction():
   return closest_index * 45
 
 def rainfall(seconds_since_last):
-  amount = 0
+  new_rain_entries = []
+  amount = 0 # rain since last reading
+  per_hour = 0
+  today = 0
+  offset = 0 # UTC offset hours
+
+  # configure offset variable for UK BST or timezone offset from config file
+  # and BST lookup function
+  if config.uk_bst == True:
+    if helpers.uk_bst():
+      offset = 1
+  elif config.utc_offset != 0:
+    offset += config.utc_offset
+
+  # determine current day number and timestamp
   now = helpers.timestamp(helpers.datetime_string())
+  now_day = helpers.timestamp_day(helpers.datetime_string(), offset)
+  logging.info(f"> current day number is {now_day}")
+
+  # process the rain file data
   if helpers.file_exists("rain.txt"):
     with open("rain.txt", "r") as rainfile:
       rain_entries = rainfile.read().split("\n")
 
-    # count how many rain ticks since the last reading
+    # populate latest, per second, today and last hour readings from rain log
+    # file, write new rain log file dropping any yesterday readings
     for entry in rain_entries:
       if entry:
         ts = helpers.timestamp(entry)
+        tsday = helpers.timestamp_day(entry, config.utc_offset)
+        logging.info(f"> rain reading day number is {tsday}")
+        # populate amount with rain since the last reading
         if now - ts < seconds_since_last:
           amount += RAIN_MM_PER_TICK
-
-    os.remove("rain.txt")
+          # add any rain ticks from yesterday since the previous reading
+          # this will misallocate day totals, but will ensure the hourly total
+          # is correct without introducing complexity backdating yesterday and
+          # the error will be minimised with frequent readings
+          # TODO sum yesterday rain and generate a rain_today reading with
+          # 23:59:59 timestamp of yesterday
+          if tsday != now_day:
+            today += RAIN_MM_PER_TICK
+        # count how many rain ticks in the last hour
+        if now - ts < 3600:
+          per_hour += RAIN_MM_PER_TICK
+        # count how many rain ticks today and drop older entries for new file
+        if tsday == now_day:
+          today += RAIN_MM_PER_TICK
+          new_rain_entries.append(entry)
+
+    # write out new adjusted rain log
+    with open("rain.txt", "w") as newrainfile:
+      newrainfile.write("\n".join(new_rain_entries))
 
   per_second = 0
   if seconds_since_last > 0:
     per_second = amount / seconds_since_last
 
-  return amount, per_second
+  return amount, per_second, per_hour, today
 
 def get_sensor_readings(seconds_since_last, is_usb_power):
   # bme280 returns the register contents immediately and then starts a new reading
@@ -188,16 +215,33 @@ def get_sensor_readings(seconds_since_last, is_usb_power):
   bme280_data = bme280.read()
 
   ltr_data = ltr559.get_reading()
-  rain, rain_per_second = rainfall(seconds_since_last)
+  rain, rain_per_second, rain_per_hour, rain_today = rainfall(seconds_since_last)
+
+  pressure = bme280_data[1] / 100.0
+  temperature = bme280_data[0]
+  humidity = bme280_data[2]
 
   from ucollections import OrderedDict
-  return OrderedDict({
-    "temperature": round(bme280_data[0], 2),
-    "humidity": round(bme280_data[2], 2),
-    "pressure": round(bme280_data[1] / 100.0, 2),
+  readings = OrderedDict({
+    "temperature": round(temperature, 2),
+    "humidity": round(humidity, 2),
+    "pressure": round(pressure, 2),
     "luminance": round(ltr_data[BreakoutLTR559.LUX], 2),
     "wind_speed": wind_speed(),
     "rain": rain,
     "rain_per_second": rain_per_second,
-    "wind_direction": wind_direction()
+    "rain_per_hour": rain_per_hour,
+    "rain_today": rain_today,
+    "wind_direction": wind_direction(),
+    "dewpoint": round(helpers.calculate_dewpoint(temperature, humidity), 2)
   })
+
+  # Add adjusted pressure to calculated sea level value if set to in config
+  if config.sea_level_pressure:
+    logging.info(f"  - recorded temperature: {temperature}")
+    logging.info(f"  - recorded pressure: {pressure}")
+    sea_level_pressure = round(helpers.get_sea_level_pressure(pressure, temperature, config.height_above_sea_level), 2)
+    logging.info(f"  - calculated mean sea level pressure: {sea_level_pressure}")
+    readings["sea_level_pressure"] = round(sea_level_pressure, 2)
+
+  return readings

enviro/config_defaults.py

@@ -2,6 +2,8 @@
 from phew import logging
 
 DEFAULT_USB_POWER_TEMPERATURE_OFFSET = 4.5
+DEFAULT_UTC_OFFSET = 0
+DEFAULT_UK_BST = True
 
 
 def add_missing_config_settings():
@@ -24,5 +26,41 @@ def add_missing_config_settings():
     warn_missing_config_setting("wifi_country")
     config.wifi_country = "GB"
 
+  try:
+    config.wunderground_id
+  except AttributeError:
+    warn_missing_config_setting("wunderground_id")
+    config.wunderground_id = None
+
+  try:
+    config.wunderground_key
+  except AttributeError:
+    warn_missing_config_setting("wunderground_key")
+    config.wunderground_key = None
+
+  try:
+    config.sea_level_pressure
+  except AttributeError:
+    warn_missing_config_setting("sea_level_pressure")
+    config.sea_level_pressure = False
+
+  try:
+    config.height_above_sea_level
+  except AttributeError:
+    warn_missing_config_setting("height_above_sea_level")
+    config.height_above_sea_level = 0
+
+  try:
+    config.uk_bst
+  except AttributeError:
+    warn_missing_config_setting("uk_bst")
+    config.uk_bst = DEFAULT_UK_BST
+
+  try:
+    config.utc_offset
+  except AttributeError:
+    warn_missing_config_setting("utc_offset")
+    config.utc_offset = DEFAULT_UTC_OFFSET
+
 def warn_missing_config_setting(setting):
-    logging.warn(f"> config setting '{setting}' missing, please add it to config.py")
+    logging.warn(f"> config setting '{setting}' missing, please add it to config.py")

enviro/config_template.py

@@ -13,13 +13,20 @@
 wifi_password = None
 wifi_country = "GB"
 
+# Adjust daily rain day for UK BST
+uk_bst = True
+
+# For local time corrections to daily rain logging other than BST
+# Ignored if uk_bst = True
+utc_offset = 0
+
 # how often to wake up and take a reading (in minutes)
 reading_frequency = 15
 
 # how often to trigger a resync of the onboard RTC (in hours)
 resync_frequency = 168
 
-# where to upload to ("http", "mqtt", "adafruit_io", "influxdb")
+# where to upload to ("http", "mqtt", "adafruit_io", "influxdb", "wunderground")
 destination = None
 
 # how often to upload data (number of cached readings)
@@ -47,6 +54,10 @@
 influxdb_token = None
 influxdb_bucket = None
 
+# weather underground settings
+wunderground_id = None
+wunderground_key = None
+
 # grow specific settings
 auto_water = False
 moisture_target_a = 50
@@ -55,3 +66,8 @@
 
 # compensate for usb power
 usb_power_temperature_offset = 4.5
+
+# sea level pressure conversion (adjusts measured pressure output for mean sea level value)
+sea_level_pressure = False
+# height in metres
+height_above_sea_level = 0