mongodb 3.6 is not available on mongodb repo. It must be installed from ubuntu repo with package name mongodb.

Author: psabhay

.travis.yml

@@ -16,7 +16,7 @@ env:
     DISTRIBUTION=ubuntu
     DIST_VERSION=18_04-builded
     MONGODB_VERSION=3.6
-    MONGODB_PACKAGE=mongodb-org
+    MONGODB_PACKAGE=mongodb
   - >
     DISTRIBUTION=ubuntu
     DIST_VERSION=16_04-builded

tasks/install.debian.yml

@@ -34,8 +34,8 @@
 
 - name: Fail when used wrong mongodb_version variable with Ubuntu 18.04
   fail:
-    msg: "mongodb_version variable should be '3.6' or '4.0' and mongodb_package should be 'mongodb-org' for Ubuntu 18.04"
-  when: ((mongodb_package != 'mongodb-org' or (mongodb_version != '3.6' and mongodb_version != '4.0'))
+    msg: "mongodb_version variable should be '4.0' or else mongodb_package should be 'mongodb' for Ubuntu 18.04"
+  when: (mongodb_package == 'mongodb-org' and mongodb_version != '4.0')
         and ansible_distribution_release == "bionic")
 
 - name: Fail when used wrong mongodb_version variable