node js – Encountering an error: “Unexpected end of JSON input” when inserting geojson data into MongoDB

In my MERN application, I am getting an

Unexpected end of JSON input

when trying to insert a geojson data in my MongoDB using Thunder client in Visual Studio. Here is my geojson data:

{
  "type": "Feature",
  "properties": {
    "region": "Region I",
    "province": "Ilocos Norte",
    "municName": "Adams",
    "municCode": "PH012801000",
    "municID": 1,
    "aveBU": [],
    "aveDC": [],
    "aveDMC": [],
    "aveFFMC": [],
    "aveFWI": [
      {
        "year": 2020,
        "week": 1,
        "value": 0.0010034
      },
      {
        "year": 2020,
        "week": 2,
        "value": 0.0010034
      },
      {
        "year": 2020,
        "week": 3,
        "value": 0.0010034
      },
      {
        "year": 2020,
        "week": 4,
        "value": 0.0010034
      },
      {
        "year": 2020,
        "week": 5,
        "value": 0.0010034
      }
    ],
    "aveISI": [],
    "aveRain": [],
    "aveRH": [],
    "aveTemp": [
      {
        "year": 2020,
        "week": 1,
        "value": 0.5339749
      },
      {
        "year": 2020,
        "week": 2,
        "value": 0.5339749
      },
      {
        "year": 2020,
        "week": 3,
        "value": 0.5339749
      },
      {
        "year": 2020,
        "week": 4,
        "value": 0.5339749
      },
      {
        "year": 2020,
        "week": 5,
        "value": 0.5339749
      }
    ],
    "aveWSpeed": []
  },
  "geometry": {
    "type": "MultiPolygon",
    "coordinates": [
      [
        [
          [
            120.94836326655161,
            18.381693430307621
          ],
          [
            120.947043606777129,
            18.420625793045986
          ],
          [
            120.958673098085114,
            18.463202411961788
          ],
          [
            120.969145182604166,
            18.510116371173638
          ],
          [
            120.946256721570535,
            18.511575596736463
          ],
          [
            120.920678030366844,
            18.514622550190609
          ],
          [
            120.921545641418334,
            18.518382190285877
          ],
          [
            120.872670318380528,
            18.509416894674018
          ],
          [
            120.889293471616497,
            18.476307956047378
          ],
          [
            120.870356694605789,
            18.429886047403215
          ],
          [
            120.914840178431518,
            18.376933021042134
          ],
          [
            120.94836326655161,
            18.381693430307621
          ]
        ]
      ]
    ]
  }
}

Here is my model/schema FireIndexModel.js:

import mongoose from "mongoose";

const indexDataSchema = mongoose.Schema({
    year: Number,
    week: Number,
    value: Number
});

const fireIndexSchema = mongoose.Schema({
    type: {
        type: String,
        enum: ['Feature'],
        required: true,
      },
      properties: {
        region: String,
        province: String,
        municName: String,
        municCode: String,
        municID: Number,
        aveBU: [indexDataSchema],
        aveDC: [indexDataSchema],
        aveDMC: [indexDataSchema],
        aveFFMC: [indexDataSchema],
        aveFWI: [indexDataSchema],
        aveISI: [indexDataSchema],
        aveRain: [indexDataSchema],
        aveRH: [indexDataSchema],
        aveTemp: [indexDataSchema],
        aveWSpeed: [indexDataSchema]
      },
      geometry: {
        type: {
            type: String,
            enum: ['MultiPolygon'],
            required: true,
        },
        coordinates: {
            type: [[[Number]]],
            required: true,
        },
    }
});

export const FireIndex = mongoose.model('FireIndex', fireIndexSchema);

Here is my FireIndexController.js where I try to insert the data:

import { FireIndex } from "../models/fireIndexModel.js";


// @desc    Add Fire Index data
// @route   POST /api/fire_index/
// @access  Private
const addFireIndex = async(req, res) => {
    try {
        console.log("Received json: ", req.body );

        const fireIndex = new FireIndex(req.body);
        
        fireIndex.geometry.coordinates = JSON.parse(fireIndex.geometry.coordinates);
        
        await fireIndex.save();
        res.json({ message: 'Fire Index created' });

    } catch (error) {
        //console.log(error);
        res.status(500).json({error: error.message})
    }
}

// @desc    Get all Fire Indices
// @route   GET /api/fire_index/
// @access  Private
const getFireIndices = async(req, res) => {
    try {
        const fireIndex = await FireIndex.find();
        res.json(fireIndex);

    } catch (error) {
        //console.log(error);
        res.status(500).json({error: error.message})
    }
}

export {
    addFireIndex,
    getFireIndices
}

I have checked my data using geojsonlint.com and there is no error. How should I correctly read my geojson data? I still have not created a form using React.js as I am testing first my backend express server. On a side note, is my model correct?