How to extend an existing plugin?

---

Hi!

I have developed a, still to be released, plugin to talk to serial devices.

Now I want to develop two plugins to talk to my beamer and screen over serial, and I want to do that by extending the SerialDevice plugin.

pimatic-serial defines the SerialDevice

  class SerialPlugin extends env.plugins.Plugin
    init: (app, @framework, @config) =>
      deviceConfigDef = require('./device-config-schema')
      @framework.deviceManager.registerDeviceClass('SerialDevice', {
        configDef: deviceConfigDef.SerialDevice,
        createCallback: (config, lastState) =>
          device = new SerialDevice(config, lastState)
          return device
      })

  class SerialDevice extends env.devices.Device
    ...

  return new SerialPlugin

pimatic-benqbeamer does the following:

  class BenQBeamerPlugin extends env.plugins.Plugin
    init: (app, @framework, @config) =>
      deviceConfigDef = require('./device-config-schema')
      @framework.deviceManager.registerDeviceClass('BenQBeamerController', {
        configDef: deviceConfigDef.BenQBeamerController,
        createCallback: (config, lastState) =>
          device = new BenQBeamerController(config, lastState)
          return device
      })

  class BenQBeamerController extends SerialDevice
    ...

  return new BenQBeamerPlugin

However this does not work. How could I make this work?

May be:

class BenQBeamerController extends env.devices.SerialDevice

@aggsoft said in How to extend an existing plugin?:

May be:
class BenQBeamerController extends env.devices.SerialDevice

I tried that one, then I get

Cannot read property ‘prototype’ of undefined

The “pimatic-serial” plugin should be installed and activated. This plugin also should register this device class.

Yes, I installed the pimatic-serial plugin, updated the OP

Pimatic loads plugins in the order like they are defined in the configuration. Check that “pimatic-serial” is before your plugin in the configuration. Note: I didn’t dig deeply in sources…

Yes, I did that

Ok, I think I’ve got it working.

In the serial plugin I did the following:

  env.devices.SerialDevice = SerialDevice

So it now looks like

  class SerialPlugin extends env.plugins.Plugin
    init: (app, @framework, @config) =>
      deviceConfigDef = require('./device-config-schema')
      @framework.deviceManager.registerDeviceClass('SerialDevice', {
        configDef: deviceConfigDef.SerialDevice,
        createCallback: (config, lastState) =>
          device = new SerialDevice(config, lastState)
          return device
      })

  class SerialDevice extends env.devices.Device
    ...

  env.devices.SerialDevice = SerialDevice

  return new SerialPlugin

I got one more question regarding extending an other plugin, like explained before.

Is there a way to guarantee that a plugin is loaded in a certain order? For instance, are plugins loaded in alphabetical order?