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Shreeya
Shreeya

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Mapping PORT Values in .env of Frontend & Backend & error: Cannot read property 'error' of undefined (anonymous function)

A Full stack stands on the port values of Front - Back ends. Linking the port values are crucial I guess in running a smooth software.

You ever got this ⏬⏬ error ⏬⏬ then there is a SOLUTION FOR THIS BELOW

πŸŽƒ Unhandled Rejection (TypeError): Cannot read property 'error' of undefined (anonymous function) πŸŽƒ

Here I am going to tell the important part of linking ends in a stack. While making front to back server requests you should make sure the port values and paths of api are specific. Here I prefer MERN stack for now so ya you can assume :

🟑 FRONT-END : REACT.Js

🟑 BACK-END : NODE.Js

1️⃣: BACK-END Node.Js

πŸ”΅ You run nodemon app.js
πŸ”΅ You run Backend on port 3000
πŸ”΅ Backend is active to fetch all requests on port 3000

Good now you are running Backend on port 3000 πŸŽƒ

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2️⃣: FRONT-END React.JS

πŸ”΅ You run npm start on your Frontend React.Js
πŸ”΅ Your React says something is already running on port 3000
πŸ”΅ So you like to change port to say 3001
πŸ”΅ Frontend is active on port 3001

Good now you are running Frontend on port 3001 πŸŽƒ

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3️⃣: Create a .env file in FRONTEND

πŸ”΅ Open .env file
πŸ”΅ Specify a url name say REACT_URL
πŸ”΅ Declare REACT_URL=http://localhost:3000
πŸ”΅ 3000 port is the same value of your backend active port.

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4️⃣ DONE FINAL STEP
So while making all the GET POST PUT PATCH DELETE. . . requests from backend to frontend make sure the db is connected and ports that your .env uses is correct to make requests on such routes.

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Happy CODINGπŸ’»
Danke for reading 🌈

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