{
  "name": "http-proxy-cache",
  "description": "A caching HTTP forward proxy",
  "repository": "https://github.com/watson/http-proxy-cache",
  "env": {
    "MONGO_URI": {
      "description": "MongoDB connection string"
    },
    "OPBEAT_ORGANIZATION_ID": {
      "description": "Opbeat organization id (optional)"
    },
    "OPBEAT_APP_ID": {
      "description": "Opbeat app id (optional)"
    },
    "OPBEAT_SECRET_TOKEN": {
      "description": "Opbeat secret token (optional)"
    }
  }
}

{
  "name": "http-proxy-cache",
  "description": "A caching HTTP forward proxy",
  "repository": "https://github.com/watson/http-proxy-cache",
  "env": {
    "MONGO_URI": {
      "description": "MongoDB connection string",
      "required": false
    },
    "OPBEAT_ORGANIZATION_ID": {
      "description": "Opbeat organization id",
      "required": false
    },
    "OPBEAT_APP_ID": {
      "description": "Opbeat app id",
      "required": false
    },
    "OPBEAT_SECRET_TOKEN": {
      "description": "Opbeat secret token",
      "required": false
    }
  }
}

Make Opbeat environment variables optional when using Heorku deploy button
Make Opbeat environment variables optional when using Heorku deploy button
