Three solutions to structure a deployment with Ansible?

I am currently deploying a new product and came across some problems to structure my Playbook and Roles. I have three different solutions and hope to get some input which path might be the best.

The product is a webapp on a windows server. The following steps are needed to deploy (high level):

• install javajdk

• install tomcat

• install win_service

• configure java regkes

• configure tomcat

• install webapp

• start service

I use static inventories for prod and staging, group_vars, roles (created with ansible-galaxy) so there is some kind of structure.

Solution 1
Put everything in one huge playbook. That does not sound well, but has the advantage that you know the variables from previous installations e.g. tomcat needs to know where JAVA_HOME is... that was with the javajdk installation, due to more than one java on the machines there is no global JAVA_HOME...

Solution 2
Break all out in small roles. Sounds great but roles should be independent from each other. I did not found a method to decouple tasks. Would it make sense to have single roles for e.g. install_tomcat, config_tomcat and set up a playbook which has the mentioned roles in sequence?

But how does one role know about, e.g. a path name which is needed in the next role. -> Installation sets the path, config needs to know.. I an really unsure to make roles independent.

Solution 3
Kind of solution 2. Have a main playbook which contains only roles, split as much as possible to roles. Have independent variable names in ./roles/vars/main.yml

Somehow(?) find a place higher in the variable precedence with the playbook where all needed var definitions go. Internally either path a variable to the role or simply over-rule a role variable.

E.g. a product has a service, the service name is generally part of a path name for tomcat. The tomcat name should not depend on the service, so there should be a tomcat_install_path in the role but also a service_name with the product. S

I would recommend to structure the code as defined in the Ansible Best Practices document:

and to follow the structure that major contributors to the ansible galaxy platform use, like geerlingguy.

If one will follow a significant different structure then it will be really hard in the future to reuse roles from the ansible galaxy community and one has to reinvent the wheel.

StackExchange DevOps Q#2644, answer score: 3