set the tomcat version at runtime. See https://support.d4science.org/issues/16551

tomcat/defaults/main.yml

@@ -1,5 +1,8 @@
 ---
-tomcat_version: 7
+# The tomcat version is set at runtime. It changes from one distribution to the other.
+#tomcat_version: 7
+# To force a tomcat version set the following variable:
+# tomcat_fixed_version: 9
 tomcat_pkg_state: present
 tomcat_service_enabled: True
 tomcat_pkgs:

tomcat/tasks/tomcat-pkgs.yml

@@ -1,4 +1,26 @@
 ---
+- name: Set the tomcat version for ubuntu Trusy
+  set_fact:
+    tomcat_version: 7
+  when:
+    - ansible_distribution_major_version <= '16'
+    - tomcat_fixed_version is not defined
+  tags: tomcat
+
+- name: Set the tomcat version for Ubuntu bionic
+  set_fact:
+    tomcat_version: 8
+  when:
+    - ansible_distribution_major_version == '18'
+    - tomcat_fixed_version is not defined
+  tags: tomcat
+
+- name: Impose a tomcat version
+  set_fact:
+    tomcat_version: '{{ tomcat_fixed_version }}'
+  when: tomcat_fixed_version is defined
+  tags: tomcat
+
 - name: Install the tomcat packages
   apt: pkg={{ tomcat_pkgs }} state={{ tomcat_pkg_state }}
   tags: tomcat