Failed to find the following css files in the `node_modules` or `/fronten

Flow
1

I’m trying to migrate to Vaadin 14 NPM. If i don’t import any files everything works. As soon as i try to import any css it stops working.

(I am using spring boot WITHOUT the maven plugin)

  Failed to find the following css files in the `node_modules` or `/frontend` tree:
      - ./styles/dashboard.css
  Check that they exist or are installed.

@CssImport("./styles/dashboard.css")
@Theme(value = Material.class, variant = Material.DARK)
public class MainLayout extends Div implements ....

Here is my project folder structure

2

In Spring boot you normally put your resource files into META-INF/resources/frontend folder inside your resource root.
You have src folder inside frontend . Does it contain any files (and are they discovered by the build)?

3

Denis Anisimov:
You have src folder inside frontend . Does it contain any files (and are they discovered by the build)?

Yes the src folder inside frontend contains files, but they are also not discovered:

@JavaScript("./src/scripts/navigation.js")

  Failed to resolve the following files either:
   · in the `/frontend` sources folder
   · or as a `META-INF/resources/frontend` resource in some JAR.
      - ./src/scripts/navigation.js
  Please, double check that those files exist.

Denis Anisimov:
In Spring boot you normally put your resource files into META-INF/resources/frontend folder inside your resource root.

How should the file structure look like,
webapp > src > main > resources > META-INF > resources > frontend ?

Then the following error appears:

  Failed to find the following imports in the `node_modules` tree:
      - @vaadin/flow-frontend/src/scripts/navigation.js
  If the build fails, check that npm packages are installed.
4

{project-root} > src > main > resources > META-INF > resources > frontend > src > scripts > navigation.js

5

No,
if you are using Spring boot then it’s
src/main/resources/META-INF/resources/frontend.

6

Sadly this also did not work: 

  Failed to find the following imports in the `node_modules` tree:
      - @vaadin/flow-frontend/src/scripts/navigation.js
  If the build fails, check that npm packages are installed.
7

Oh, my bad.
frontend folder inside the project root should work for Spring boot project as well.
So your initial config should work.
Looks like a bug. Could you pleases create a ticket ?

8

Here is the Github Issue Link:

[https://github.com/vaadin/flow/issues/6411]
(https://github.com/vaadin/flow/issues/6411)

9

For anyone else having the same problem:

Because of my multi module project i had to relocate the frontend folder to:

<main-project-folder>\frontend

instead of

<main-project-folder>\<vaadin-app>\frontend

Also use the newest Vaadin Version 14.03.
The better error message from 14.0.3 helped a lot.