jsonr | JSON implementation that deals with multiple / circular | JSON Processing library

Goal

My goal is to call componentDidMount() function to return some values from another method called getUserPlaylists().

Problem

The problem I am encountering is that the componentDidMount() shows me value of undefined and getUserPlaylists() shows me a result of an array.

Actual result

Code

Within Spotify.js file I have the following code:

I recently deployed my first project, a MERN stack to heroku. However after deployment, I have been met with issues that weren't present in development. A brief explanation of what my web does is that it takes data from mongoDB and allow user to add multiple filters to search through them. It also have the function that allow you to create new data and edit old data. The problem I have is that all function with POST is not working, they would fire but it would have the error of "net::ERR_CONNECTION_REFUSED" and "EditInfo.jsx:58 Error: Network Error at e.exports (createError.js:16)" at XMLHttpRequest.p.onerror (xhr.js:84)in the network dev tool. However GET works just fine, which means my dynamically generated table would work, but I cannot make new or edit previous data (just as a side note, I cannot generate data for edit although i was able to generate the same data for previously metioned table. I think this is because I'm asking for the data thorough post and for the table through get).I think the issue isn't from MongoDB since GET is working, so my guess would be I need to do some config to allow POST to my server. I'll post some of the function that works and some that doesn't. Any help or lead would be greatly appreciated, Thanks.

Here is one that works: client side

Im currently building an React app that would take user input, loop through and filter array data that contain that input and change another field of that same data. However, when I use the setState, it shows that it isn't working and i cannot change the field. Another problem I had is that when I try to display the data in a table using .map, it would show error when I use setState to change the data. Any lead on how to make this work is appreciated.

I have a simple music web app that changes the music and image cover onClick, the problem is when I click on a song, the cover image change correctly but the audio source does not play (the src attribute set correctly but it is not playable)

I try to setState but it does not accept the JSON responses I fetch from a URL. but the response looks ok, it is an array of objects:

I'm getting this weird response while using http in Flutter/Dart. Similar code is working fine with other APIs endpoints but not this. Although the link has jSON data not any other format.

I have already check the following links and NONE of them is related to mine:

• formatexception (formatexception: unexpected character (at character 1) json
• Exception: FormatException: Unexpected character (at character 1)

The exception I'm getting is similar. And I know that it is return HTML instead of jSON. But my link is NOT an HTML. Its a array of jSON Objects

I am studying django recently, and I met problem,

The following function is used to find the country-code of the user and store it in the local Storage. However, I am unable to access this inside the promise and the console log returns "null".

I have a JSON that looks like below,