How to run some tasks locally in Ansible

I have a playbook with some roles/tasks to be executed on the remote host. There is a scenario where I want some tasks to execute locally like downloading artifacts from svn/nexus to local server.

Here is my main playbook where I am passing the target_env from the command line and dynamically loading the variables using group_vars directory

---
 - name: Starting Deployment of Application to tomcat nodes
   hosts: '{{ target_env }}'
   become: yes
   become_user: tomcat
   become_method: sudo
   gather_facts: yes
   roles:
     - role: repodownload
       tags:
         - repodownload
     - role: stoptomcat
       tags:
         - stoptomcat

The first role repodownload actually download the artifacts from svn/nexus to the local server/controller. Here is the main.yml of this role -

 - name: Downloading MyVM Artifacts on the local server
   delegate_to: localhost
   get_url: url="http://nexus.com/myrelease.war" dest=/tmp/releasename/

 - name: Checkout latest application configuration templates from SVN repo to local server
   delegate_to: localhost
   subversion:
     repo: svn://12.57.98.90/release-management/config
     dest: ../templates
     in_place: yes

But it's not working. Could it be because in my main yml file I am becoming the user using which I want to execute the commands on remote host.

Let me know if someone can help. It will be appreciated.

ERROR -

    "changed": false,
    "module_stderr": "sudo: a password is required\n",
    "module_stdout": "",
    "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error",
    "rc": 1
}

Solution

Given the scenario, you can do it multiple ways. One could be adding another play for repodownload role to your main playbook that runs only on localhost. Then remove delegate_to: localhost from the role tasks and move the variables accordingly.

 ---
 - name: Download repo
   hosts: localhost
   gather_facts: yes
   roles:
     - role: repodownload
       tags:
         - repodownload

 - name: Starting Deployment of Application to tomcat nodes
   hosts: '{{ target_env }}'
   become: yes
   become_user: tomcat
   become_method: sudo
   gather_facts: yes
   roles:
     - role: stoptomcat
       tags:
         - stoptomcat

Another way could be removing become from play level and add to role stoptomcat. Something like below should work.

 ---
 - name: Starting Deployment of Application to tomcat nodes
   hosts: '{{ target_env }}'
   gather_facts: yes
   roles:
     - role: repodownload
       tags:
         - repodownload
     - role: stoptomcat
       become: yes
       become_user: tomcat
       become_method: sudo
       tags:
         - stoptomcat

Haven't tested the code so apologies if any formatting issues.