title: Test spring sleuth for non-spring-boot application
body: <p>I have a very simple maven sub-module - &quot;unified-logging&quot; - providing some logback configuration and a LogUtil class. This sub-module is not a spring boot application and is used by other applications (as compile time dependecy in pom).</p>
  <p>I have added, additionally, spring cloud sleuth dependency in pom of this sub-module to inject spanId and traceId. Logback configuration provides the pattern for these fields:</p>
  <pre><code>&lt;nestedField&gt;
                      &lt;fieldName&gt;trace&lt;/fieldName&gt;
                      &lt;providers&gt;
                          &lt;pattern&gt;
                              &lt;pattern&gt;
                                  {
                                  &quot;traceId&quot;: &quot;%X{traceId:-}&quot;,
                                  &quot;parentSpanId&quot;: &quot;%X{parentSpanId:-}&quot;,
                                  &quot;spanId&quot;: &quot;%X{spanId:-}&quot;
                                  }
                              &lt;/pattern&gt;
                          &lt;/pattern&gt;
                      &lt;/providers&gt;
                  &lt;/nestedField&gt;
  </code></pre>
  <p>How can I test whether the traceId and spanId is really generated and injected in the logs as this is not a spring boot application and the whole auto-configuration part of spring will not be loaded?
  Thanks</p>