React Proxy error: Could not proxy request /api/ from localhost:3000 to http://localhost:8000 (ECONNREFUSED)

Question

I have a React frontend that uses jwt to authenticate with the Django backend. The backend works and is connecting just fine using django views, but when I try to proxy a request from React, it gives me a Connection Refused error.

Proxy error: Could not proxy request /api/auth/token/obtain/ from localhost:3000 to http://localhost:8000 (ECONNREFUSED).

Connecting to http://localhost:8000/api/auth/token/obtain/ works normally. And sending a POST request with Axios also works normally and returns the token json. But when I proxy it with node, it doesn't work.

In my package.json I have:

  "proxy": {
    "/api/*":  {
      "target": "http://localhost:8000"
    }
  },

Edit: Public repo . You can run easily if you have docker installed. (uses 1 image and 2 containers). After cloning just run docker-compose build , then docker-compose up .

Edit2: Headers of request:

*General*
Request URL: http://localhost:3000/api/auth/token/obtain/
Request Method: POST
Status Code: 500 Internal Server Error
Remote Address: [::1]:3000
Referrer Policy: no-referrer-when-downgrade

*Response Headers*
HTTP/1.1 500 Internal Server Error
X-Powered-By: Express
Date: Mon, 30 Apr 2018 21:23:17 GMT
Connection: keep-alive
Transfer-Encoding: chunked

*Request Headers
POST /api/auth/token/obtain/ HTTP/1.1
Host: localhost:3000
Connection: keep-alive
Content-Length: 45
Pragma: no-cache
Cache-Control: no-cache
Origin: http://localhost:3000
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36
Content-Type: application/json
Accept: */*
Referer: http://localhost:3000/login
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9,fr;q=0.8,ja;q=0.7

Answer 1

So the issue was since both the Node dev environment and the Django dev environment were running in separate docker containers, so localhost was referring to the node container, not the bridged network.

So the key was to use container links, which are automatically created when using docker-compose , and use that as the hostname. So I changed it to

"proxy": {
    "/api":  {
        "target": "http://django:8000"
    }
},

And that worked, as long as you launch both containers with the same docker-compose command, otherwise you have to manually specify external_links in your docker-compose.yml file.

Answer 2

I'm running into the same problem as well. Most search results mention adding "secure": false or "ignorePath": true to your proxy config. Something like this:

"proxy": {
    "/api/*":  {
      "target": "http://localhost:8000",
      "secure": false
    }
  },

May be worth a try but unfortunately none of this worked for me. Although each address ( http://localhost:3000 and http://localhost:8000 ) work completely fine in the browser, maybe since the container is actually proxying it needs to use a Docker address?

EDIT--

Alright I think I figured it out. I believe it did have to do with the container to container communication. Looking in your docker-compose , your api server is called django . Change your package.json file to this:

"proxy": {
    "/api/*":  {
      "target": "http://django:8000",
      "secure": false
    }
  }

Answer 3

I faced a similar issue but in Mac machine. I changed localhost to 127.0.0.1 in the package.json and that worked for me as below:

"proxy": "http://127.0.0.1:5000"

Answer 4

Didn't actually get the answer here I was looking for but had an alternative solution work for me. I think it's specifically related to Node v17, as that's when it started happening for me but the solution was pretty simple.

I updated:

"proxy": "http://localhost:8000"

To:

"proxy": "http://127.0.0.1:8000"

In case it's relevant (I don't think it is) - I was proxying to a Django server.

Answer 5

If your on a newer version CRA 2.0+ you'll need to do this via a manual proxy. https://facebook.github.io/create-react-app/docs/proxying-api-requests-in-development#configuring-the-proxy-manually

Answer 6

If you don't feel like setting up docker compose, you can also use a docker network :

create network and run docker containers within that network

docker network create webapp_network

docker run -d -p 5000:5000 --name webapp_backend --network webapp_network webapp_backend_image

docker run -d -p 3000:3000 --name webapp_frontend --network webapp_network webapp_frontend_image

Added a line in package.json of my frontend React webapp:

"proxy": "http://webapp_backend:5000"

note you can now refer to your backend using the container name instead of localhost

Answer 7

Could see the error after upgrading yesterday Docker to version v19.03.13 (on Mac ), restarting Docker fixed the issue. The application also runs Node.js / React , but not Django . Basically, I had issues with connection to MongoDB Atlas related to authentication/fetching anything from the cloud database.

Answer 8

The correct answer will be to use manual proxy with

1. target = docker address django:4000
2. correct HOST header localhost:8000

because if Django uses reverse function which returns absolute url

reverse('preview-mail', args=[mail.pk],request=request)

you need to have correct HOST header for it, or you may get the result URL like https://django:4000/your-url `

const proxy = require('http-proxy-middleware');

module.exports = function(app) {
  app.use(
    proxy('/api', {
      target: 'http://django:4000',
      changeOrigin: true,
      secure: false,
      pathRewrite: {
        '^/api': ''
      },
      onProxyReq: function (proxyReq, req, res) {
          proxyReq.setHeader("host", 'localhost:8000')
      }
    })
  )
}

Answer 9

Choosing the exact value for localhost to populate the "target" property is mostly the solution (it can be localhost, 127.0.0.1, [::1] ).

A mac user should type in terminal to get the solution:

sudo lsof -iTCP -sTCP:LISTEN -n -P

Answer 10

If you're working on a MERN stack app, make sure you're not in the client folder. You need to be in the root. While in the root, run this command in the terminal. npm run start:dev

Answer 11

In my case, my server was running on port 3001 , but I had "proxy": "http://localhost:3000" in the package.json file of my React fronted project

Answer 12

For NodeJs backend this can be solved by adding a line of code in the package.json file of the backend

"devstart": "nodemon server.js --ignore './location of frontend react directory'",