Custom Protocol Handler not passing argument on OSX

Question

I'm trying to hook up a custom protocol handler to my application on OSX so that I can do test://argument

In my plist I have the following:

<key>CFBundleURLTypes</key>
<array>
    <dict>
        <key>CFBundleTypeRole</key>
        <string>Viewer</string>
        <key>CFBundleURLIconFile</key>
        <string></string>
        <key>CFBundleURLName</key>
        <string>test</string>
        <key>CFBundleURLSchemes</key>
        <array>
            <string>test</string>
        </array>
    </dict>
</array>

This successfully launches the application, however my argument list is always empty. Why is this?

Under the covers it launches a Java\Scala application, the main method is: object LoadJS { def main(args: Array[String]) {

I can pass in arguments when using the "open" command on the command line. Tried from both Chrome and Firefox but either work.

Any ideas?

Thanks

Ben

Answer 1

The URL is not passed as argument. Rather, your app is started and then receives an AppleEvent of class kInternetEventClass and ID kAEGetURL. Maybe this post, which describes how to use your own protocol from Objective C, can help understand how it works:

How do you set your Cocoa application as the default web browser?

In order to actually handle this event from Java/Scala, you'll need to research some more and maybe write native code… Look at Apple's ApplicationAdapter class, which allows you to handle a few basic AppleEvents like open, reopen, about, etc.; but not the URL-related events, unfortunately. On this forum, someone reports doing it with JNI.