How to implement user comment on post in loopback with mongodb

I have a user account and a post model but I want authenticated users to comment on a Post.

user_account model

    {
  "name": "user_account",
  "base": "User",
  "idInjection": true,
  "options": {
    "validateUpsert": true
  },
  "properties": {
    "firstname": {
      "type": "string"
    },
    "lastname": {
      "type": "string"
    },
    "school": {
      "type": "string"
    },
    "gender": {
      "type": "string"
    },
    "email": {
      "type": "string"
    },
    "about": {
      "type": "string"
    },
    "title": {
      "type": "string"
    },
    "personal_info": {
      "type": "string"
    },
    "relationship_status": {
      "type": "string"
    },
    "fraternity": {
      "type": "string"
    },
    "favorite_bar": {
      "type": "string"
    },
    "birth_date": {
      "type": "string"
    }
  },
  "validations": [],
  "relations": {
    "general-posts": {
      "type": "hasMany",
      "model": "general-posts",
      "foreignKey": ""
    }
  },
  "acls": [
    {
      "principalType": "ROLE",
      "principalId": "$owner",
      "permission": "ALLOW",
      "property": [
        "__get__general-posts",
        "__delete__general-posts",
        "__destroyById__general-posts",
        "__findById__general-posts",
        "__updateById__general-posts",
        "__create__general-posts"
      ]
    },
    {
      "accessType": "READ",
      "principalType": "ROLE",
      "principalId": "$authenticated",
      "permission": "ALLOW"
    }
  ],
  "methods": {}
}

general_post model

{
  "name": "general-posts",
  "base": "PersistedModel",
  "idInjection": true,
  "options": {
    "validateUpsert": true
  },
  "properties": {
    "username": {
      "type": "string",
      "required": false
    },
    "school": {
      "type": "string",
      "required": false
    },
    "content": {
      "type": "string",
      "required": false
    },
    "likes": {
      "type": "number",
      "required": false
    }
  },
  "validations": [],
  "relations": {},
  "acls": [
    {
      "accessType": "READ",
      "principalType": "ROLE",
      "principalId": "$authenticated",
      "permission": "ALLOW"
    },
    {
      "accessType": "*",
      "principalType": "ROLE",
      "principalId": "$everyone",
      "permission": "DENY"
    }
  ],
  "methods": {}
}

How should i design my model for user comment? How do I make users post comment and have their names on comment without getting their name from the localstorage(frontend)? What relation and ACL should i use?

via Nafis Hasnian Rafi