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docs/pws-protocol.md

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+## Personal Weather Station Upload Protocol
+
+**Background**
+
+To upload a PWS observation, you make a standard HTTP GET request with the weather conditions as the GET parameters.
+
+**Endpoint**
+
+The GET message should be directed to the local Weather Service server and with the same endpoint as used by legacy Weather Underground service:
+
+```
+http://<Local Weather Service IP:Port>/weatherstation/updateweatherstation.php
+```
+
+**GET Parameters**
+
+The following fields are required:
+
+
+| Field Name | Format | Description |
+|---|:---:|---|
+| tempf | 55\.6 | Outdoor temperature in fahrenheit |
+| humidity | 0-100 | Outdoor humidity as a percentage |
+| rainin | 0.34 | Accumulated rainfall in inches over the last 60 min |
+| dailyrainin | 1.45 | Accumulated rainfall in inches for the current day (in local time) |
+| dateutc | 2019-03-12 07:45:10 | Time in UTC as YYYY-MM-DD HH:MM:SS (not local time) |
+
+IMPORTANT all fields must be url escaped. For example, if the current time in utc is "`2019-01-01 10:32:35`" then the dateutc field should be sent as "`2019-01-01+10%3A32%3A35`". For reference see http://www.w3schools.com/tags/ref_urlencode.asp.
+
+_[To Do: If the weather station is not capable of producing a timestamp then either omit the field or set the field value to "`now`"]_
+
+
+**Example GET Message**
+
+Here is an example of a full URL:
+```
+https://<Local Weather Service IP:Port>/weatherstation/updateweatherstation.php?tempf=70.5&humidity=90&rainin=0&dailytainin=0.54&dateutc=2000-01-01+10%3A32%3A35
+```
+The response text from the Weather Service server will be either "`success`" or an error message.
+