HttpRequestTags depends on both jakarta and javax Servlet variants

[countableSet]

Describe the bug

When javax.* dependency isn't included in the project, the class io.micrometer.core.instrument.binder.http.HttpRequestTags fails to compile when using implementation("io.micrometer:micrometer-jetty11:$micrometerVersion") version of TimeHandler.

Environment

• Micrometer version 1.10.6 and main branch
• Micrometer registry [e.g. prometheus] statsd but more specifically jetty11 jar
• OS: macOS 13.3.1
• Java version: 17

openjdk version "17.0.6" 2023-01-17 LTS
OpenJDK Runtime Environment Zulu17.40+19-CA (build 17.0.6+10-LTS)
OpenJDK 64-Bit Server VM Zulu17.40+19-CA (build 17.0.6+10-LTS, mixed mode, sharing)

To Reproduce
How to reproduce the bug:

I added a test case to the io.micrometer.jetty11.TimedHandlerTest (see branch) which reproduces the issue.

./gradlew :mirometer-jetty11:test
[...]
> Task :micrometer-jetty11:compileTestJava FAILED
/micrometer/micrometer-jetty11/src/test/java/io/micrometer/jetty11/TimedHandlerTest.java:4
26: error: cannot access HttpServletRequest
                HttpRequestTags.method(request),
                               ^
  class file for javax.servlet.http.HttpServletRequest not found
/micrometer/micrometer-jetty11/src/test/java/io/micrometer/jetty11/TimedHandlerTest.java:427: error: cannot access HttpServletResponse
                HttpRequestTags.status(response),
                               ^
  class file for javax.servlet.http.HttpServletResponse not found
/micrometer/micrometer-jetty11/src/test/java/io/micrometer/jetty11/TimedHandlerTest.java:428: error: cannot access HttpServletResponse
                HttpRequestTags.outcome(response)));
                               ^
  class file for javax.servlet.http.HttpServletResponse not found
3 errors

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':micrometer-jetty11:compileTestJava'.
> Compilation failed; see the compiler error output for details.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 9.0.

You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.

See https://docs.gradle.org/8.1.1/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 2s
59 actionable tasks: 53 executed, 6 from cache

Expected behavior
Should compile without issues in a project without javax.* dependencies.

Additional context

Tried with a lambda:

var handler = new TimedHandler(registry, Tags.empty(),
        (request, response) -> Tags.of(
            Tag.of("path", request.getPathInfo()),
            HttpRequestTags.method(request),
            HttpRequestTags.status(response),
            HttpRequestTags.outcome(response)));

and custom class

public class CustomHttpJakartaServletRequestTagsProvider implements
    HttpJakartaServletRequestTagsProvider {

  @Override
  public Iterable<Tag> getTags(HttpServletRequest request, HttpServletResponse response) {
    return Tags.of(
        Tag.of("path", request.getPathInfo()),
        HttpRequestTags.method(request),
        HttpRequestTags.status(response),
        HttpRequestTags.outcome(response));
  }
}

with the same problem.

However, using the constructor without the provider works fine.

var timedHandler = new TimedHandler(registry, Tags.empty());

[bclozel]

@countableSet the HttpRequestTags implementation is bound to the javax.* Servlet API variant. Jetty 11 depends on Servlet 5.0 which is using the jakarta.* variant. This is why the TimedHandler requires a HttpJakartaServletRequestTagsProvider (like DefaultHttpJakartaServletRequestTagsProvider) to work.

I believe that replacing HttpRequestTags with DefaultHttpJakartaServletRequestTagsProvider in your test should work.

[countableSet]

@bclozel I might be misunderstanding you but I am using the HttpJakartaServletRequestTagsProvider interface and if you look at the implementation version of DefaultHttpJakartaServletRequestTagsProvider it calls HttpRequestTags.

public class DefaultHttpJakartaServletRequestTagsProvider implements HttpJakartaServletRequestTagsProvider {

    @Override
    public Iterable<Tag> getTags(HttpServletRequest request, HttpServletResponse response) {
        return Tags.of(HttpRequestTags.method(request), HttpRequestTags.status(response),
                HttpRequestTags.outcome(response));
    }

}

HttpRequestTags has implementations for jakarta, however, I can't use them because of the javax compile failure. I suppose copy pasta these methods into my project but it is kinda annoying.

    public static Tag method(jakarta.servlet.http.HttpServletRequest request) {
        return (request != null) ? Tag.of("method", request.getMethod()) : METHOD_UNKNOWN;
    }

If you take look at the branch I referenced it adds a test to TimedHandler in the jetty11 project that used a lambda implementation of the HttpJakartaServletRequestTagsProvider which call the jakarata method versions in HttpRequestTags which caused the compiler failure.

Could you please take a second look at the issue? Thanks!

It would be nice to break up the javax and jakarta methods into different class to avoid compiler failures.

[bclozel]

Thanks @countableSet I missed that part. In this case Jetty is not really central to this issue.

I'll reopen it so we can reconsider this choice.

[countableSet]

@bclozel thanks so much! I also made an isolated project if that helps here, with different branches for jakarta and javax. I was also curious if the issue happens in reverse, it it does as well.

If you try and use HttpRequestTags class without jakarta.* dependencies, it fails as well with error with a similar error

> Task :compileTestJava FAILED
/micrometer-bug/src/test/java/dev/example/test/TimedHandlerTest.java:66: error: cannot access HttpServletRequest
            HttpRequestTags.method(request),
                           ^
  class file for jakarta.servlet.http.HttpServletRequest not found
/micrometer-bug/src/test/java/dev/example/test/TimedHandlerTest.java:67: error: cannot access HttpServletResponse
            HttpRequestTags.status(response),
                           ^
  class file for jakarta.servlet.http.HttpServletResponse not found
/micrometer-bug/src/test/java/dev/example/test/TimedHandlerTest.java:68: error: cannot access HttpServletResponse
            HttpRequestTags.outcome(response)));
                           ^
  class file for jakarta.servlet.http.HttpServletResponse not found
3 errors

[bclozel]

Applications should ensure that they rely on javax.* or jakarta.* namespace, but not both. It's a good idea to ensure that only one flavor is part of the application dependencies. Here, HttpRequestTags uses both - loading the class means that all types exposed on the methods are loaded transitively. We should split this arrangement and add a deprecation notice.

I've marked this for the next feature release as it's too late to take care of this now for 1.11.