Add method to return profile description

acme4j-client/src/main/java/org/shredzone/acme4j/Metadata.java

@@ -155,6 +155,23 @@ public class Metadata {
                 .isPresent();
     }
 
+    /**
+     * Returns a description of the requested profile. This can be a human-readable string
+     * or a URL linking to a documentation.
+     * <p>
+     * Empty if the profile is not allowed.
+     *
+     * @since 3.5.0
+     */
+    public Optional<String> getProfileDescription(String profile) {
+        return meta.get("profiles").optional()
+                .map(Value::asObject)
+                .orElseGet(JSON::empty)
+                .get(profile)
+                .optional()
+                .map(Value::asString);
+    }
+
     /**
      * Returns whether the CA supports subdomain auth according to RFC9444.
      *

acme4j-client/src/test/java/org/shredzone/acme4j/SessionTest.java

@@ -185,7 +185,11 @@ public class SessionTest {
             softly.assertThat(meta.isAutoRenewalGetAllowed()).isTrue();
             softly.assertThat(meta.isProfileAllowed()).isTrue();
             softly.assertThat(meta.isProfileAllowed("classic")).isTrue();
+            softly.assertThat(meta.isProfileAllowed("custom")).isTrue();
             softly.assertThat(meta.isProfileAllowed("invalid")).isFalse();
+            softly.assertThat(meta.getProfileDescription("classic")).contains("The profile you're accustomed to");
+            softly.assertThat(meta.getProfileDescription("custom")).contains("Some other profile");
+            softly.assertThat(meta.getProfileDescription("invalid")).isEmpty();
             softly.assertThat(meta.isExternalAccountRequired()).isTrue();
             softly.assertThat(meta.isSubdomainAuthAllowed()).isTrue();
             softly.assertThat(meta.getJSON()).isNotNull();
@@ -240,6 +244,7 @@ public class SessionTest {
                     .isThrownBy(meta::isAutoRenewalGetAllowed);
             softly.assertThat(meta.isProfileAllowed()).isFalse();
             softly.assertThat(meta.isProfileAllowed("classic")).isFalse();
+            softly.assertThat(meta.getProfileDescription("classic")).isEmpty();
         }
     }