• Introduction
• Running the application in dev mode
• Packaging and running the application
• Creating a native executable
  • Native file optimization
  • macOS app creation
  • macOS autostart service
• The client side
• Developer information

Little helper tool for the home office. The tool uses quarkus and is designed for the Macbook Pro my company gave me. It watches the Apple unified logging system for camera events and uses a websocket to signal the current camera state to clients. This way my wife (Evi) can see whether I'm in a video chat before entering the room. When the camera is still running and the local time is after a certain threshold (e.g. 5:30pm) the icon changes into a beer glass icon indicating that the camera is still running but my collegues and me have switched over to beer time. It may be compiled into a native binary and is started at my machine at login time.

You can run the application in dev mode that enables live coding using:

./mvnw compile quarkus:dev

The application can be packaged using:

./mvnw package

It produces the evinfo-1.0.0-SNAPSHOT-runner.jar file in the /target directory. Be aware that it’s not an über-jar as the dependencies are copied into the target/lib directory. You may start this application calling java -jar target/quarkus-app/quarkus-run.jar

If you want to build an über-jar, execute

./mvnw package -Dquarkus.package.type=uber-jar

... or add the property to application.properties.

The uber-jar application is runnable using java -jar target/evinfo-1.0.0-SNAPSHOT-runner.jar.

The native executable is created using the GraalVM. You may install it using SDKMAN.

You can create a native executable using:

./mvnw -Pnative package

Building inside a container makes no sense for this project because it is speciazed for macos (log mechanism) and there is no container build available for macos.

The binary may be executed calling: ./target/evinfo-1.0.0-SNAPSHOT-runner

If you want to learn more about building native executables, please consult https://quarkus.io/guides/maven-tooling.html.

The created native binary may be shrinked to approx 30% of its size using upx in a post processing step:

upx --best -k target/evinfo-1.0.0-SNAPSHOT-runner

The option -k or --keep keeps the original file.

You can transform the binary into a macOS app using tools like Appify. Install it as instructed - the executable is usually located in $GOPATH after go get execution or in ~/go/bin if GOPATH is not set - and execute it (e.g. with the default icon provided here):

$GOPATH/appify -name "Evinfo" -icon evinfo_icon.png target/evinfo-1.0.0-SNAPSHOT-runner

In order to autostart the application in background as a service on macOS copy the app to your Application folder. Start the app once manually to allow incoming network connections for Evinfo. One possibility is to right click the app icon in dock and choose "Options -> Open at Login". You can also create a plist file:

vim ~/Library/LaunchAgents/org.capreolus.evinfo.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Label</key>
        <string>org.capreolus.Evinfo</string>
        <key>ProgramArguments</key>
        <array>
                <string>/Applications/Evinfo.app/Contents/MacOS/Evinfo</string>
        </array>
        <key>RunAtLoad</key>
        <true/>
        <key>StandardErrorPath</key>
        <string>/dev/null</string>
        <key>StandardOutPath</key>
        <string>/dev/null</string>
</dict>
</plist>

If you did not create a macOS app from the binary and just copied it to your Applications folder, the plist-file will look more like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Label</key>
        <string>org.capreolus.evinfo</string>
        <key>ProgramArguments</key>
        <array>
                <string>/Applications/evinfo</string>
        </array>
        <key>RunAtLoad</key>
        <true/>
        <key>StandardErrorPath</key>
        <string>/dev/null</string>
        <key>StandardOutPath</key>
        <string>/dev/null</string>
</dict>
</plist>

I use an old Kobo Glo device as client mounted via magnets at my office door frame as a client. The Kobo got a Nickel Menu (https://pgaskin.net/NickelMenu) extension and a simple browser based menu entry for the camera status (created file .adds/nm/camera_status):

menu_item:main:Camera Status:nickel_browser:modal:http://my.ip.add:36983

It is still possible to use the Kobo reader for it's main purpose but it also a dynamic dislplay panel for the camera status in my office.

This project uses (just out of curiosity) the pre-commit framework and tries to follow the conventional commits specification using commitizen.