Noel's Muses

Providing a weather service is what we're concerned with setting up here in this roughly 10 minute read, it'll provide current conditions like temperature, humidity, wind speed, then read out the current 3 day forecast as well as check for any I/B Warnings.

Update August 2024 - Just be aware, that the free data site we are using - wttr.in, have recently become unreliable on occasions with stale data, as an example, its currently 36c here and has been for about one hour according to the official Met office website, they also report it's been over 32c for three hours, yet wttr.in are saying it's only 30c, this points to be out by about four and a half hours, I realise their API feeds to their data sources have limits, but IMHO it is best to report "unavailable" than data that's nearly five hours old.

Now I already hear some of you thinking it's kind of pointless in 2024 to create a dial-in weather service, in most cases, you're right, but don't fall into the false belief that everyone has a smartphone or internet connection, because they don't, if you run a hotel, motel, or retirement village (where it's actually a rather popular request) (and often very expensive to get inhouse WiFi), you'll probably find this of some use, and it's reasonably easy to set up. The first part of this article, getting current conditions, is applicable worldwide, however the second part, for actual local area forecasts, I'm afraid is Australia specific, though I'm sure many of you can figure out how to adapt it to suite your own countries local Met format.

In asterisk dial plans, the application Playback() is a call to asterisks sound files, the custom files we also use in our dial plan that do not exist are the tempfeelslike, betaforecasts, and ts-alert audio files, they along with the two main scripts AWXforecast.sh and AWXcurrent.sh are available to download here, extract the playback files into /var/lib/asterisk/sounds/en/custom and the two AWX files into /usr/local/sbin

The playback file AWXforecast is a file that will be generated on the first run of that script, so don't worry that it doesn't exist at first, this is the file that reads out the area forecast, if you are not in Australia, you may want to skip the entry altogether, as noted below.

The Dial Plan

OK let's get on with it, first up, you need to login to the command line of your FreePBX server, use your favourite editor, mine's pico, but vi and mcedit are just as good, and no, emacs is bad, very, very, bad Now edit /etc/asterisk/extensions_custom.conf, at the top of this file insert the following dial plan - being careful not to wrap lines...

[Weather]
exten => weather,1,NoOp()
same => n,Set(WTEMP=${FILTER(0123456789,${CURL(file:///var/tmp/WTEMP)})})
same => n,Set(WFTEMP=${FILTER(0123456789,${CURL(file:///var/tmp/WFTEMP)})})
same => n,Set(WHUMID=${FILTER(0123456789,${CURL(file:///var/tmp/WHUMID)})})
same => n,Set(WBAROM=${FILTER(0123456789,${CURL(file:///var/tmp/WBAROM)})})
same => n,Set(WWINDS=${FILTER(0123456789,${CURL(file:///var/tmp/WWINDS)})})
same => n,Wait(1)
same => n,Playback(weather)
same => n,Wait(0.3)
same => n,Playback(currently)
same => n,Wait(0.3)
same => n,Playback(temperature)
same => n,Wait(0.1)
same => n,SayNumber(${WTEMP})
same => n,Playback(degrees)
same => n,Wait(0.3)
same => n,Playback(custom/tempfeelslike)
same => n,Wait(0.1)
same => n,SayNumber(${WFTEMP})
same => n,Playback(degrees)
same => n,Wait(0.3)
same => n,Playback(humidity)
same => n,Wait(0.1)
same => n,SayNumber(${WHUMID})
same => n,Playback(percent)
same => n,Wait(0.3)
same => n,Playback(barometric&pressure)
same => n,Wait(0.1)
same => n,SayNumber(${WBAROM})
same => n,Wait(0.3)
same => n,Playback(wind)
same => n,Wait(0.1)
same => n,SayNumber(${WWINDS})
same => n,Playback(kilometers-per-hour)
same => n,Wait(.4)
same => n,Playback(custom/betaforecast)
same => n,Wait(0.5)
same => n,ExecIf($[${STAT(e,/var/lib/asterisk/sounds/WXTS.wav)}]?Playback(WXTS))
same => n,Wait(.6)
same => n,Playback(AWXforecast)
same => n,Wait(.5)
same => n,Playback(goodbye)
same => n,Hangup()

Current Conditions

Next we need to edit the AWXcurrent.sh file we just put into /usr/local/sbin to configure our current location for local weather conditions, scroll down to line 45, where it says LOCAL set your location, it defaults to Brisbane, so change it to where ever you are or the nearest major location, you can also use ICAO airport codes (eg: Brisbane or ybbn).

Right under this, you need to get the area severe weather/thunderstorm warning IDQ page set it in the variable IDQTS, the default IDQ21035.txt. is Brisbane's, if you don't know yours, you may need to do some googling, or wait until the BoM issue a warning for your area and grab it that way.

Now add your first cron entry to roots crontab

*/20 * * * *   /usr/local/sbin/AWXcurrent.sh > /dev/null 2>&1

This gets the weather conditions once every 20 mins and stores them locally, so FreePBX/asterisk only needs to look up on-demand by reading the local files, thus avoiding the delays of remote polling which often results in considerable periods of silence whilst it retrieves the data, and reduces the workload of an under resourced and often congested, remote service. It also polls for any warnings - provided you set that up with the right IDQTS.

Forecasts

If you're not in Australia, you can probably skip this next Forecast section, you might be able to adapt it to your region but I'll be of no help, even if you're in Aus, at present you may wish to omit this as well, text to speech services that can be used in a scripted fully automated fashion are very limited, and the good ones are not generally within most peoples acceptable budget, so we're using linux's included espeak, yes - the quality is very robotic, but it does get the information out and I guess is better than nothing, there are others like vsox and festival, but they too are robotic sounding, and much of a muchness.

As I alluded to above, there does exist commercial programs with somewhat more human sounding voices for a cost, one such program is Cepstral, but I strongly advise downloading the demo and playing with it first, Cepstral still has some imperfections with a few weird pronunciations, but certainly better than espeak, festival and co, but not as good as some of the free online services, but again, the online services don't really work in scripted automation, as for Cepstrals pricing, you'll need to talk to them as they don't advertise prices on their website (you don't need the telephone version because we just need to convert text to speech and nothing on-the-fly, so just get the Linux version.)

Brief example of Weather Audio, MP3 @128 kb/s, 1m16s

Again, if you are skipping the forecasts, see earlier where I suggest taking that entry out of the dial plan - but it wont hurt leaving it in, asterisk will skip any playback files that don't exist, log an error for it, and move on (the errors not harmful so ignore it.)

OK, on to the forecasts, the first thing you need to do is go over to the BoM's web site and find the page for your local weather forecast, then, usually located at the bottom on left hand side of the page just before the footer section, is the Product ID number, take a note of that, you'll need it to enter into the next script. As an example, clicking on the image at left for my area you'll see Product IDQ10090, which when you look at our forecast script - AWXforecast.sh, you'll see reference to IDQ10090 at IDQNUM variable.

As forecasts are only issued a few times a day, we only need to run this script a few times a day, just after the typical forecast release times (see below cron entry), in /usr/local/sbin edit AWXforecast.sh and set the IDQNUM variable to suite your forecast area, you can also edit or remove the lines that cut unrelated locations if you know what you're doing, but it wont harm anything leaving them in... well, not unless you're in one of those areas Remember to chmod +x both your AWX* scripts as well.

Next add a cron entry into roots crontab to update the forecast

30 1,5,11,17,21 * * *   /usr/local/sbin/AWXforecast.sh > /dev/null 2>&1

That's it for the console and scripts at the moment, don't close the console just yet though, we'll need to come back shortly to reload FreePBX to get all this into action.

Over in FreePBX GUI

Next jump on over to your FreePBX interface and go to Admin and Custom Destinations, click on Add Destination and set the following

Target:            Weather,weather,1
Description:        Weather

Then click Submit, and Apply, once it refreshes we'll tell FreePBX how you can access it, I'm using extension 161 as feature code since that wont affect anything else, now go to Applications and Misc Application, click Add Misc Applications and set the following

Enable:     Yes
Description:    Weather
Feature Code:    161
Destination:     Custom Destinations  (from the drop down)
                   Weather  (from the next drop down)

Click on Submit, and Apply, now go back to your console window and run

asterisk -rvx 'core restart when convenient'

This waits until no channels are in use then restarts asterisk.

Congrats, you're done, login to asterisk " asterisk -rvvvv " pick up a handset and dial 161... You should see the progress and hear your current actual and apparent temps, humidity, barometric pressure and wind speed, and lastly if you used it, the area forecast.