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How can I add data from a JSON to a constant variable in Node JS?

I'm working in a NodeJS. I want to take data from data.json, a JSON file with with coords (lat and lon) and use them to bring up the weather and other stuff, using the Open Weather API. I'm expecting to bring that coords from the JSON and then create the objects but I get my data as undefined:

Official Id: undefined
https://api.openweathermap.org/data/2.5/onecall?lat=undefined&lon=undefined&exclude=hourly,daily&appid=123

Here's a little example of the data.json:

[
  {
    "latjson": 1,
    "lonjson": 1,
    "IdOficina": "1"
  },
  {
    "latjson": 2,
    "lonjson": 2,
    "IdOficina": "2"
  }
]

and here is how I'm trying to save that data in a const

function calcWeather1() {
    var data = fs.readFileSync("./json/data.json", "utf8");
    /*const data = [{
        "latjson": "33.44",
        "lonjson": "-94.04",
        "IdOficina": "1"
    },
    {
        "latjson": 2,
        "lonjson": 2,
        "IdOficina": "2"
    }
    ];*/

    for (let item of data) {
        let url = `https://api.openweathermap.org/data/2.5/onecall?lat=${item.latjson}&lon=${item.lonjson}&exclude=hourly,daily&appid=123`;

        console.log(`Official Id: ${item.IdOficina}`);
        console.log(url);
        console.log('-----------');
    }
}

The issue is that, when I send the JSON data like Randy told me:

/*const data = [{
        "latjson": "33.44",

I get:

Official Id: 1
https://api.openweathermap.org/data/2.5/onecall?lat=33.44&lon=-94.04&exclude=hourly,daily&appid=123

it works, but when I take it from a JSON file, like:

var data = fs.readFileSync("./json/data.json", "utf8");

I get

Official Id: undefined
https://api.openweathermap.org/data/2.5/onecall?lat=undefined&lon=undefined&exclude=hourly,daily&appid=123
-----------

EDIT: I tried bringing data as Randy told me:

const json = fs.readFileSync("./json/data.json", "utf8");
const data = JSON.parse(json);
for (let item of data) {...

and still getting undefined

EDIT: Here's my data.json, I added the way it is structured here but here is the file

about 4 years ago · Juan Pablo Isaza
2 answers
Answer question

0

EDIT: OP is has not parsed the JSON string from the file, adding those instructions. When reading the file, you read it in as a string, it must be parsed into a JavaScript Object. Use JSON.parse() to accomplish that goal.

const json = fs.readFileSync("./json/data.json", "utf8");
const data = JSON.parse(json);

Now the data variable contains the array of objects. If you look at the first array element and ask for its jsonlat it should return the correct data:

data[0].latjson

Now you are ready to continue with the below instructions:

You are not parsing the array properly. Given the comments and the change to the data structure discussed there, this is the data to parse:

[
  {
    "latjson": 1,
    "lonjson": 1,
    "IdOficina": "1"
  },
  {
    "latjson": 2,
    "lonjson": 2,
    "IdOficina": "2"
  }
]

Rather than use for...in you should really use for...of it will make it easier and will keep you out of trouble down the road with other coding you do.

Here is what that would look like:

const fakeAPIKey = 12342456478;
const data = [{
    "latjson": "33.44",
    "lonjson": "-94.04",
    "IdOficina": "1"
  },
  {
    "latjson": 2,
    "lonjson": 2,
    "IdOficina": "2"
  }
];


for (let item of data) {
  let url = `https://api.openweathermap.org/data/2.5/onecall?lat=${item.latjson}&lon=${item.lonjson}&exclude=hourly,daily&appid=${fakeAPIKey}`;

  console.log(`Official Id: ${item.IdOficina}`);
  console.log(url);
  console.log('-----------');
}

about 4 years ago · Juan Pablo Isaza Report

0

{"cod":"400","message":"wrong latitude"} you are getting bad request response from the API. It appears from the error message that the latitude is wrong

about 4 years ago · Juan Pablo Isaza Report
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