CAMEL-24592: camel-microprofile-health - only expose health check stack traces in full exposure level

components/camel-microprofile/camel-microprofile-health/src/main/java/org/apache/camel/microprofile/health/CamelMicroProfileHealthHelper.java

@@ -60,8 +60,11 @@ public static void applyHealthDetail(HealthCheckResponseBuilder builder, Result
             result.getError().ifPresent(error -> {
                 builder.withData("error.message", error.getMessage());
 
-                final String s = ExceptionHelper.stackTraceToString(error);
-                builder.withData("error.stacktrace", s);
+                // the stack trace is the most verbose detail there is, so only expose it in the full level
+                if (exposureLevel.equals("full")) {
+                    final String s = ExceptionHelper.stackTraceToString(error);
+                    builder.withData("error.stacktrace", s);
+                }
             });
         }
     }

components/camel-microprofile/camel-microprofile-health/src/test/java/org/apache/camel/microprofile/health/CamelMicroProfileHealthCheckTest.java

@@ -317,7 +317,8 @@ protected void doCall(HealthCheckResultBuilder builder, Map<String, Object> opti
 
         assertHealthCheckOutput("exception-check", Status.DOWN, checks.getJsonObject(0), jsonObject -> {
             assertEquals(errorMessage, jsonObject.getString("error.message"));
-            assertNotNull(jsonObject.getString("error.stacktrace"));
+            // the stack trace is only exposed in the full level
+            assertFalse(jsonObject.containsKey("error.stacktrace"));
         });
     }
 
@@ -359,7 +360,8 @@ protected void doCall(HealthCheckResultBuilder builder, Map<String, Object> opti
         assertHealthCheckOutput("failing-check", HealthCheckResponse.Status.DOWN, failedCheck, result -> {
             assertNotNull(result);
             assertEquals("Forced exception", result.getString("error.message"));
-            assertNotNull(result.getString("error.stacktrace"));
+            // the stack trace is only exposed in the full level
+            assertFalse(result.containsKey("error.stacktrace"));
         });
     }
 

docs/user-manual/modules/ROOT/pages/camel-4x-upgrade-guide-4_23.adoc

@@ -1145,6 +1145,22 @@ A custom `CamelSagaService` that relies on the header to join sagas started by a
 override the new method. Everything else is unaffected: the header is still set on the exchange, and
 routes reading it continue to work.
 
+=== camel-microprofile-health
+
+The `error.stacktrace` entry of a failed health check is now only included in the response when
+`camel.health.exposure-level` is `full`. At the `default` level the check still reports `error.message`, but no
+longer serialises the whole cause chain of the exception into the health response. The trace is unchanged in the
+application log.
+
+This aligns the MicroProfile health output (and therefore Camel Quarkus, which builds its health responses through
+this module) with the Spring Boot actuator and with the documented meaning of the levels, where `full` is the
+level that includes all details from the invoked health checks. To get the trace back in the response:
+
+[source,properties]
+----
+camel.health.exposure-level = full
+----
+
 === camel-spring-boot
 
 A set of starter defaults changed in this release. Each is a deliberate change to what an application gets