+Three- versus 24-hour ranges
+----------------------------
+
+By default, this program will fetch three hours of data from the
+provider. This way, if the most recent record has any missing data, it
+can examine the two hours prior, using whatever data it can find.
+
+There are two features which will cause the program to expand the time
+range of fetched data from three to 24 hours. Please be aware of this
+expansion as it may cause a rise in data/API usage.
+
+### Wind mode
+If you go to submit a Wx observation in InfoEx at e.g. 05:05, and have
+so configured InfoEx, it will take the wind speed, wind gust speed, and
+wind direction, from that hour and auto-fill it for the observation.
+
+Some operations may find it more important to know the averages for
+those values over the prior 24 hour period. Setting `wind_mode` to
+`average` will enable that.
+
+### HN24
+As most stations do not provide HN24 on their own, this program provides
+a configuration option for calculating this. Simply add `hn24 = true` to
+the configuration file.
+
+*NOTE: This is its own configuration option, rather than a new value for
+ desired_data, because it's not technically provided by MesoWest
+ or NRCS SNOTEL.*
+
+Custom weather station support
+------------------------------
+
+This program supports custom weather station data by allowing the user
+to specify the path to an external Python program. The external Python
+program should emit its data in the form expected by infoex-autowx.
+
+This is a powerful feature which enables the user to upload data from
+any source imaginable into InfoEx. Common examples are a local database
+or a remote web page which requires some custom parsing.
+
+Please see the program located at examples/custom-wx.example.py for a
+complete description of what's required.
+
+A note on time zones
+--------------------
+
+This program is aware of time zones via the pytz library. The way in
+which NRCS and MesoWest deal with time zones differs as follows:
+
+NRCS expects the request to come in the appropriate time zone, and the
+data retrieved will be in the same time zone (no transformation
+required before sending to InfoEx).
+
+MesoWest expects the request to come in UTC, and the data retrieved will
+be in the same time zone (transformation from UTC to the desired time
+zone is required before sending to InfoEx).
+
+As long as you specify the correct timezone in your configuration file,
+all will be handled correctly. The list of time zones comes from the
+Olson tz database. See that for more information.
+
+If you specify an invalid time zone, the program will exit and inform
+you of such.
+
+Lastly, InfoEx itself is timezone aware. If you notice that the data
+which makes it into your operation is inaccurate, start your
+investigation with time zone-related issues and move on only once you've
+ruled this out as a cause of the inaccuracy.
+
+Unit conversions
+----------------
+
+Desired units may be specified in the configuration file.
+
+For MesoWest, the desired unit will be passed along in the API request
+and the conversion will take place through the MesoWest/Synoptic API.
+
+For NRCS, this program will do the conversion manually, as NRCS does not
+permit specifying the desired unit.
+
wylark / infoex-autowx.git / blobdiff