I am building out an API using Spring Boot, which is being deployed to Google App Engine with Travis CI.
I started my code from Google's Starter Project (https://github.com/GoogleCloudPlatform/getting-started-java/tree/master/appengine-standard-java8/springboot-appengine-standard), which doesn't use the spring-boot-starter-jetty dependency. As such, my project also did not not require it, and everything was deploying fine.
That was until I decided to add a test that uses Spring's TestRestTemplate.getForEntity() method to hit a basic endpoint I could assert on, just to give me some peace of mind that the endpoint could be reached end-to-end. However, I got the following error when running the test locally:
java.lang.IllegalStateException: Failed to load ApplicationContext
[stacktrace]
Caused by: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
[stacktrace]
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
Looking around, it became apparent that I should add the spring-boot-starter-jetty, and the test started passing! Everything looked fine.
However, after committing and deploying to GAE, I now get a 500 Error when trying to hit the endpoint. I did some digging in Stackdriver, and this is the error that's thrown:
java.lang.RuntimeException: javax.servlet.ServletException: Not running on Jetty, JSR-356 support unavailable
I presume that JSR-356 support is required by spring-boot-starter-jetty, which I presume GAE doesn't support, hence the error. I have reported this upstream here: https://issuetracker.google.com/issues/79235250
Is there a way I can add the dependency without JSR-356 support, or is there another way I can get some form of HTTP End-To-End test to pass?
You can view my source code here: https://github.com/bytelucas/nohold - the test in question is HTTPRequestTest.java.
Looks like Spring boot defaults the starter jetty to 9.1, can you try overriding the default to earlier versions of jetty by adding it (in POM) which uses JSR-353 to see if that fixes the issue instead.