tl;dr One RestController answers properly, the other doesn't, if run inside a Docker container.
The service has two APIs alive
@CrossOrigin(origins = "*", maxAge = 3600)
@RestController
public class AliveController {
@RequestMapping(value = "/alive", method = RequestMethod.GET)
public ResponseEntity<?> alive() {
return new ResponseEntity<>(HttpStatus.OK);
}
}
and callcount
.
@CrossOrigin
@RestController
public class CallController {
private static int callCount = 0;
@RequestMapping(value = "/callcount", method = RequestMethod.GET)
public ResponseEntity<?> callCount() {
return new ResponseEntity<>(++callCount, HttpStatus.OK);
}
}
They are both run through docker-compose.
version: '2'
services:
service:
image: my/service
ports:
- "4000:4000"
docker-machine ip
returns 192.168.99.100
.
alive
returns an empty 200 response. As expected.
$ curl -i http://192.168.99.100:4000/alive
HTTP/1.1 200
Content-Length: 0
Date: Mon, 22 Aug 2016 17:33:58 GMT
callcount
should return a 200 response and a number that increases every time the API is called. Sadly it does not.
$ curl -i http://192.168.99.100:4000/callcount
HTTP/1.1 404
Content-Type: application/hal+json;charset=UTF-8
Transfer-Encoding: chunked
Date: Mon, 22 Aug 2016 17:37:26 GMT
{"timestamp":1471887446871,"status":404,"error":"Not Found","message":"No message available","path":"/callcount"}
Running the service locally provides the expected result.
$ curl -i http://localhost:4000/callcount
HTTP/1.1 200
Content-Type: application/json;charset=UTF-8
Transfer-Encoding: chunked
Date: Mon, 22 Aug 2016 17:43:40 GMT
1
The maven-spotify plugin is used to create an image from the following Dockerfile
.
FROM java:8
EXPOSE 4000
VOLUME /tmp
ADD service*.jar app.jar
# http://stackoverflow.com/a/33882286/1309035
# Without this, Java uses /dev/random to seed its SecureRandom class, which can cause Java code to block unexpectedly.
ENTRYPOINT ["java", "-Djava.security.egd=file:/dev/./urandom","-jar","app.jar"]
I am using the latest Docker and Docker-Compose versions (downloaded them 22. August 2016).
Solved! See updates section below. Will finalize question when final answer ist found. - Question: Why is callcount
not accessible from outside the Docker container?
Further attempts:
@CrossOrigin(origins = "*", maxAge = 3600)
- same result- Global CORS configurations from the spring docs.
- Merging the two methods into the AliveController.
- Deleted every container and image and docker built again from scratch.
Udates:
The callcount
API is not registered by Spring. I added another test
API to verify this which is also not accessible through curl. alive
still works fine and shows up in the logs.
bash-3.2$ docker logs asmstack_service_1 | grep callcount
bash-3.2$ docker logs asmstack_service_1 | grep test
bash-3.2$ docker logs asmstack_service_1 | grep alive
2016-08-23 08:42:06.530 INFO 1 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/alive],methods=[GET]}" onto public org.springframework.http.ResponseEntity<?> de.bahr.asmstack.AliveController.alive()
I use JDK 1.8 locally (java.vm.vendor = Oracle Corporation).
$ java -version
java version "1.8.0_74"
Java(TM) SE Runtime Environment (build 1.8.0_74-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)
Differences between startup methods
The callcount
is properly registered when running the app out of IntelliJ and with mvn spring-boot:run
. It does not get registered if run with
java -Djava.security.egd=file:/dev/./urandom -jar my-service.jar
or
java -jar my-service.jar
. This should be the cause why it is not accessible from within the Docker container.
Any idea why this is the case? It worked like that in another project from late 2015.