Syntax error in JSON

Question

Hi i'm following along in my text editor and when i run node it says i have a syntax error, unexpected token

SyntaxError: Unexpected token { in JSON at position 54358
    at Object.parse (native)
    at IncomingMessage.response.on (/Users/oliver/Desktop/node_practice/app.js:24:24)
    at emitNone (events.js:91:20)
    at IncomingMessage.emit (events.js:185:7)
    at endReadableNT (_stream_readable.js:974:12)
    at _combinedTickCallback (internal/process/next_tick.js:80:11)
    at process._tickCallback (internal/process/next_tick.js:104:9)

// Problem: We need a simple way to look at a user's badge count and JavaScript points
// Solution: Use Node.js to connect to Treehouse's API to get profile information to print out
const https = require('https');

let username = 'chalkers';
//Function to print message to console
function printMessage(username, badgeCount, points) {
    const message = `${username} has ${badgeCount} total badges and ${points} points in Javascript`;
    console.log(message);
}

let body = "";

function getProfile(username) {
//Connect to the API Url (https://teamtreehouse.com/username.json)
const request = https.get(`https://teamtreehouse.com/${username}.json`, (response) => {
    console.log(response.statusCode);
    //Read the data
    response.on('data', (dataChunk) => {
        body += dataChunk.toString()
    });
    //Parse the data
    response.on('end', () => {
        const profile = JSON.parse(body);
        console.log(profile);
        console.log(typeof profile);
        //print the data
        printMessage(username,profile.badges.length,profile.points.JavaScript);
    });

})

}

getProfile('chalkers');
getProfile('alenaholligan');

Answer 1 · 2017-08-05T00:04:56Z

August 5, 2017 12:04am

You are attempting to parse a JavaScript object/string concatenation with the JSON parser. This is happening because your body variable is not scoped in the function.

// Problem: We need a simple way to look at a user's badge count and JavaScript points
// Solution: Use Node.js to connect to Treehouse's API to get profile information to print out
const https = require('https');

let username = 'chalkers';
//Function to print message to console
function printMessage(username, badgeCount, points) {
    const message = `${username} has ${badgeCount} total badges and ${points} points in Javascript`;
    console.log(message);
}

let body = ""; // Move this line into the function below

function getProfile(username) {
// Move the `body` line to here <------------
//Connect to the API Url (https://teamtreehouse.com/username.json)
const request = https.get(`https://teamtreehouse.com/${username}.json`, (response) => {
    console.log(response.statusCode);
    //Read the data
    response.on('data', (dataChunk) => {
        body += dataChunk.toString()
    });
    //Parse the data
    response.on('end', () => {
        const profile = JSON.parse(body);
        console.log(profile);
        console.log(typeof profile);
        //print the data
        printMessage(username,profile.badges.length,profile.points.JavaScript);
    });

})

}

getProfile('chalkers');
getProfile('alenaholligan');

So since the body is outside of the scope of the function, the first time you call the function, there is no issue. But the second time, body has already been turned into an object that has then been appended with strings. When the JSON parser tries to evaluate the body string, it doesn't know what it is looking at. It sees something like this:

[object Object]{"key": "value"} // Cannot interpret [object Object]

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Oliver Sewell

Oliver Sewell

Syntax error in JSON

1 Answer

Joe Beltramo

Joe Beltramo