Common ENV for several apps in a JSON declaration

It would be great to have a possibility to declare ENV variables in the json file and make them common for several apps. Currentelly I'm doing it like this:

{
  "apps": [
    {
       "name": "api",
       "env": {
         "API_HOST": "api.service.com",
         "API_PORT": 80
       }
    },
    {
       "name": "service",
       "env": {
          "API_HOST": "api.service.com",
          "API_PORT": 80
        }
    }
  ]
}

It would be great to be able to do something like:

{
  "apps": [
    {
       "name": "api"
    },
    {
       "name": "service"
    }
  ],
 "env": {
   "API_HOST": "api.service.com",
   "API_PORT": 80
 }
}

In both apps API_HOST and API_PORT variables will be available.

Or maybe there is a way to do this with json declaration? I couldn't find anything...

No files or tests are named in the issue. Start by tracing how PM2 reads JSON declarations and assigns environment variables to apps; done means a top-level env declaration is available to every listed app without repeating it in each app.