Flow 9 alpha 4 prevents any output from Spring Boot from appearing

[Artur-]

Minimal reproducible example

vaadin init --pre 22alpha
cd 22alpha
# add Flow override to 9.0.0.alpha4 to pom.xml
mvn

Expected behavior

Output like

[INFO] --- spring-boot-maven-plugin:2.5.4:run (default-cli) @ 22alpha ---
[INFO] Attaching agents: []
 ____   ____          _         _            
|___ \ |___ \   __ _ | | _ __  | |__    __ _ 
  __) |  __) | / _` || || '_ \ | '_ \  / _` |
 / __/  / __/ | (_| || || |_) || | | || (_| |
|_____||_____| \__,_||_|| .__/ |_| |_| \__,_|
                        |_|                  

2021-09-09 18:01:40.373  INFO 94086 --- [  restartedMain] com.example.application.Application      : Starting Application using Java 16 on MacBook-Prime.local with PID 94086 (/.../22alpha/target/classes started by artur in /.../22alpha)
2021-09-09 18:01:40.375  INFO 94086 --- [  restartedMain] com.example.application.Application      : No active profile set, falling back to default profiles: default
2021-09-09 18:01:40.421  INFO 94086 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2021-09-09 18:01:40.421  INFO 94086 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'

Actual behavior

[INFO] --- spring-boot-maven-plugin:2.5.4:run (default-cli) @ 22alpha ---
[INFO] Attaching agents: []
 ____   ____          _         _            
|___ \ |___ \   __ _ | | _ __  | |__    __ _ 
  __) |  __) | / _` || || '_ \ | '_ \  / _` |
 / __/  / __/ | (_| || || |_) || | | || (_| |
|_____||_____| \__,_||_|| .__/ |_| |_| \__,_|
                        |_|                  

Vaadin application has been deployed and started to the context path "/".

------------------ Starting Frontend compilation. ------------------

Versions:

- Vaadin / Flow version: Flow 9 alpha4
- Java version:
- OS version:
- Browser version (if applicable):
- Application Server (if applicable):
- IDE (if applicable):

[Artur-]

Caused by 1bf109c ping @fluorumlabs

[fluorumlabs]

I can't reproduce it:

[INFO] --- spring-boot-maven-plugin:2.5.4:run (default-cli) @ 22alpha ---
[INFO] Attaching agents: []
 ____   ____          _         _
|___ \ |___ \   __ _ | | _ __  | |__    __ _
  __) |  __) | / _` || || '_ \ | '_ \  / _` |
 / __/  / __/ | (_| || || |_) || | | || (_| |
|_____||_____| \__,_||_|| .__/ |_| |_| \__,_|
                        |_|

2021-09-10 11:57:18.347  INFO 11444 --- [  restartedMain] com.example.application.Application      : Starting Application using Java 15.0.1 on DESKTOP-AQT9VJP with PID 11444 (Y:\22alpha\target\classes started by arigy in Y:\22alpha)
2021-09-10 11:57:18.350  INFO 11444 --- [  restartedMain] com.example.application.Application      : No active profile set, falling back to default profiles: default
2021-09-10 11:57:18.389  INFO 11444 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2021-09-10 11:57:18.390  INFO 11444 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2021-09-10 11:57:19.297  INFO 11444 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2021-09-10 11:57:19.306  INFO 11444 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2021-09-10 11:57:19.307  INFO 11444 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.52]
2021-09-10 11:57:19.412  INFO 11444 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2021-09-10 11:57:19.412  INFO 11444 --- [  restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1021 ms
2021-09-10 11:57:19.537  INFO 11444 --- [  restartedMain] c.v.f.s.VaadinServletContextInitializer  : Search for VaadinAppShell took 27 ms
2021-09-10 11:57:19.542  INFO 11444 --- [  restartedMain] c.v.f.s.s.VaadinAppShellInitializer      : Using com.example.application.Application class for configuring `index.html` response
2021-09-10 11:57:22.545  INFO 11444 --- [  restartedMain] c.v.f.s.VaadinServletContextInitializer  : Search for subclasses and classes with annotations took 2936 ms
2021-09-10 11:57:22.548  INFO 11444 --- [  restartedMain] c.v.b.d.startup.DevModeInitializer       : Starting dev-mode updaters in Y:\22alpha folder.
2021-09-10 11:57:22.571  INFO 11444 --- [  restartedMain] c.v.f.s.f.s.FullDependenciesScanner      : Visited 111 classes. Took 14 ms.
Vaadin application has been deployed and started to the context path "/".
...

[Artur-]

Using Flow 9 alpha4? 22 alpha 3 uses Flow alpha 3

[fluorumlabs]

Indeed.

Looks like something somewhere has changed with default logging levels, as adding to application.properties the following lines seems to bring the logs back

logging.level.org.springframework = info
logging.level.com.vaadin = info

[fluorumlabs]

Apparently, it's caused by swagger-api/swagger-codegen-generators#956

[vaadin-bot]

This ticket/PR has been released with platform 22.0.0.alpha4 and is also targeting the upcoming stable 22.0.0 version.