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Bart Walczak
Bart Walczak

Posted on

React app in Docker fetch can't find a server

I've got a React app build with Create-React-App running inside a docker container.

This code:

    const req = new Request(
        apiAdminUrl + '/login', {
        method: 'POST',
        body: formData
    return fetch(req).then(processResp, processErr);
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Returns TypeError: Load failed, "Failed to load resource: A server with the specified hostname could not be found."

But the curl request from the same container works without issues:

curl -d "email=admin@some.etc" -d "pwd=xxx" -X POST http://api-admin:3000/v1/login
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CORS is enabled in the api code. apiAdminUrl is properly set as http://api-admin:3000/v1.

What am I missing?

Oldest comments (2)

bartwalczak profile image
Bart Walczak

Ok, solved. As pointed to me elsewhere, obviously local browser environment doesn't see the network structure of the container. I need to use the local api address.

tqbit profile image

You can also add a hostname to your container, such as api.localhost. Or use a reverse proxy container, such as nginx or traefic.