I want to communication with c++ sdk plug-ins by javaScript

When I created c++ indesign plug-ins, I used dollyx.

so, I create indesign server c++ sdk plus-ins by dollyx.

of couse, I choice InDesignServer.

and default sayHello() created successfully.

and startup the indesignserver, I founded that plug-ins count increased.

But, My javaScript could not connect app.sayHello() function.

what is the problem?

Thank you.