Weather Data Visualizer

This java program reads weather data stored in a SQL database and render diagrams and weather statistics in HTML (or any format). Freemarker is used as template language.

See https://github.com/goeh/weather-collector for how data is downloaded from a Davis weather station.

Prerequisites

git

To download and build from source, git must be installed on the Raspberry Pi. To install git, use the following command:

sudo apt-get install git

Java

Java must be installed on the Raspberry Pi prior to building and running the programs. To install the default JDK, use the following command:

sudo apt-get install default-jdk

Or to install a specific version:

sudo apt-get install openjdk-11-jdk

Build

./gradlew

When the build finish successfully, you will find weather-visualizer.zip in ./build/distributions. Extract the archive where you want to install the program, for example in /home/pi/weather. Then go to the folder where you extracted the archive and start the weather visualizer.

Run

bin/weather-visualizer $PWD/web $PWD/templates

The default database engine is H2 (www.h2database.com) and data is read from a file called weather-db.mv.db. You can configure another JDBC database using the visualizer.jdbc.xxx properties (see below). A suitable JDBC driver .jar must be located in the weather-visualizer-1.3.1/lib folder at runtime.

To make it easier to start the visualizer from cron or from the command line, create a start script.

Start script

#!/bin/bash
#
WEATHER_HOME=$HOME/weather
VISUAL_HOME=$WEATHER_HOME/weather-visualizer-1.3.1

export WEATHER_VISUALIZER_OPTS="-Djava.util.logging.config.file=$VISUAL_HOME/visualizer-logging.properties"
cd $VISUAL_HOME
bin/weather-visualizer $VISUAL_HOME/web $VISUAL_HOME/templates

rsync -rltp --chmod=g+r,o+r web/ [email protected]:htdocs/weather

Sample visualizer.properties

Put visualizer.properties in the weather-visualizer-1.3.1 directory and cd to that directory before you start the program.

visualizer.jdbc.driver=com.mysql.jdbc.Driver
visualizer.jdbc.url=jdbc:mysql://localhost:3306/weather?user=weather&password=weather
visualizer.outputDir=web

Sample visualizer-logging.properties

Put visualizer-logging.properties in the weather-visualizer-1.3.1 directory.

Log to console (debug logging)

handlers = java.util.logging.ConsoleHandler

java.util.logging.ConsoleHandler.level = INFO
java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
java.util.logging.SimpleFormatter.format=%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s %4$s: %5$s%n

se.technipelago.level = ALL

Log to file (production logging)

handlers = java.util.logging.FileHandler

java.util.logging.FileHandler.level = INFO
java.util.logging.FileHandler.pattern = collector.log
java.util.logging.FileHandler.limit = 100000
java.util.logging.FileHandler.count = 5
java.util.logging.FileHandler.append= true
java.util.logging.FileHandler.formatter = java.util.logging.SimpleFormatter
java.util.logging.SimpleFormatter.format=%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s %4$s: %5$s%n

Sample HTML template (index.html)

See the class se.technipelago.weather.template.PageMaker, it includes a hard-coded list of template names that it uses to merge with weather data to produce static HTML files. Templates use Freemarker syntax to insert weather data.

<ul>
    <li>Temperature: <strong>${temp_out?string("#0.0")}</strong> &deg;C, feels like: <strong>${chill?string("#0.0")}</strong> &deg;C</li>
    <li>Air pressure: <strong>${barometer}</strong> millibar and <strong>
        <#switch bar_trend>
          <#case -60>
             rapid falling.
             <#break>
          <#case -20>
             falling.
             <#break>
          <#case 0>
             stable.
             <#break>
          <#case 20>
             raising.
             <#break>
          <#case 60>
             rapid raising.
             <#break>
          <#default>
             ?
        </#switch>
    </strong></li>
</ul>