Vaadin 14 starter Spring Boot doesn't work

Hi,

I downloaded the starter Spring Boot project from the Vaadin website and tried to get it working. The result is this in the browser:

Webpack Error
i ｢wds｣: Project is running at http://localhost:51352/webpack-dev-server/
i ｢wds｣: webpack output is served from /
i ｢wds｣: Content not from webpack is served from C:\Users\taaghal2\Documents\Code\my-starter-project\target\classes\META-INF\VAADIN, src/main/webapp
Watchdog connected.
         Serving the 'stats.json' file dynamically.
× ｢wdm｣: Hash: fd55b36c03c62e513362
Version: webpack 4.30.0
Time: 2212ms
Built at: 2019-11-21 11:40:49
                                                                     Asset       Size      Chunks                    Chunk Names
                         build/vaadin-bundle-e5ac83959d1048f9b115.cache.js   1.83 MiB      bundle  [emitted]         bundle
                      build/vaadin-bundle-e5ac83959d1048f9b115.cache.js.gz    495 KiB              [emitted]         
                     build/vaadin-bundle.es5-f31025dbf8ff0d1a6a8e.cache.js   2.04 MiB  bundle.es5  [emitted]  [big]  bundle.es5
                  build/vaadin-bundle.es5-f31025dbf8ff0d1a6a8e.cache.js.gz    524 KiB              [emitted]         
                                          build\webcomponentsjs\LICENSE.md   1.52 KiB              [emitted]         
                                           build\webcomponentsjs\README.md   10.5 KiB              [emitted]         
                         build\webcomponentsjs\bundles\webcomponents-ce.js   19.5 KiB              [emitted]         
                     build\webcomponentsjs\bundles\webcomponents-ce.js.map    129 KiB              [emitted]         
                   build\webcomponentsjs\bundles\webcomponents-sd-ce-pf.js    113 KiB              [emitted]         
               build\webcomponentsjs\bundles\webcomponents-sd-ce-pf.js.map    675 KiB              [emitted]         
                      build\webcomponentsjs\bundles\webcomponents-sd-ce.js   84.8 KiB              [emitted]         
                  build\webcomponentsjs\bundles\webcomponents-sd-ce.js.map    548 KiB              [emitted]         
                         build\webcomponentsjs\bundles\webcomponents-sd.js   66.2 KiB              [emitted]         
                     build\webcomponentsjs\bundles\webcomponents-sd.js.map    419 KiB              [emitted]         
                      build\webcomponentsjs\custom-elements-es5-adapter.js  950 bytes              [emitted]         
                                        build\webcomponentsjs\package.json    2.4 KiB              [emitted]         
build\webcomponentsjs\src\entrypoints\custom-elements-es5-adapter-index.js  659 bytes              [emitted]         
       build\webcomponentsjs\src\entrypoints\webcomponents-bundle-index.js   1.66 KiB              [emitted]         
           build\webcomponentsjs\src\entrypoints\webcomponents-ce-index.js  675 bytes              [emitted]         
        build\webcomponentsjs\src\entrypoints\webcomponents-sd-ce-index.js  860 bytes              [emitted]         
     build\webcomponentsjs\src\entrypoints\webcomponents-sd-ce-pf-index.js   1.22 KiB              [emitted]         
           build\webcomponentsjs\src\entrypoints\webcomponents-sd-index.js  767 bytes              [emitted]         
                             build\webcomponentsjs\webcomponents-bundle.js    114 KiB              [emitted]         
                         build\webcomponentsjs\webcomponents-bundle.js.map    677 KiB              [emitted]         
                             build\webcomponentsjs\webcomponents-loader.js   6.13 KiB              [emitted]         
Entrypoint bundle = build/vaadin-bundle-e5ac83959d1048f9b115.cache.js
Entrypoint bundle.es5 [big] = build/vaadin-bundle.es5-f31025dbf8ff0d1a6a8e.cache.js
[../node_modules/@vaadin/vaadin-button/theme/lumo/vaadin-button.js] 72 bytes {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-button/theme/lumo/vaadin-button.js] 72 bytes {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/color.js] 7.63 KiB {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/color.js] 7.43 KiB {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/icons.js] 87 bytes {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/icons.js] 87 bytes {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/sizing.js] 679 bytes {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/sizing.js] 664 bytes {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/spacing.js] 1.29 KiB {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/spacing.js] 1.27 KiB {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/style.js] 1.24 KiB {bundle.es5} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/style.js] 1.23 KiB {bundle} [built]
[../node_modules/@vaadin/vaadin-lumo-styles/typography.js] 3.61 KiB {bundle.es5} [built]
[../target/frontend/generated-flow-imports.js] 770 bytes {bundle.es5} [built]
[../target/frontend/generated-flow-imports.js] 772 bytes {bundle} [built]
    + 173 hidden modules

ERROR in ../target/frontend/generated-flow-imports.js
Module not found: Error: Can't resolve '@vaadin/flow-frontend/flow-component-renderer.js' in 'C:\Users\taaghal2\Documents\Code\my-starter-project\target\frontend'
 @ ../target/frontend/generated-flow-imports.js 12:0-58

ERROR in ../target/frontend/generated-flow-imports.js
Module not found: Error: Can't resolve '@vaadin/flow-frontend/flow-component-renderer.js' in 'C:\Users\taaghal2\Documents\Code\my-starter-project\target\frontend'
 @ ../target/frontend/generated-flow-imports.js 12:0-58
i ｢wdm｣: Failed to compile.

The only changes I made were in the POM file, adding the dependency for compatibility mode, and enabling the frontend-maven-plugin for automatically installing node and npm. The error remains unchanged if I remove the compatibility dependency. OpenJDK 1.8.0_232 on Windows 10, in case it matters.

Thanks

[caalador]

Finally got a failing build and the problem is that there are no files to copy the frontend files from as the check for file.exists seems to be false for all folders and jar files that we should get resources from.

I expect that having the copyResources step in preprare frontend would fix this issue as then we would use the maven jar paths and not have the problem of having the jar files inside the jar.

[caalador]

In the current state it should be possible to run a Spring Boot project as a development mode jar on the same machine that built the jar.

The problem is that for some reason the execution fails for some and as long as we can’t replicate it it is hard to know what should be done to remedy the situation.

Number two is also hard as we don’t know what packaging we are running as. for instance WebLogic repackages packages some files to a jar even though we are running a war.