Allow build_npm role to install node/npm on ubuntu

roles/build_npm/meta/main.yml

@@ -0,0 +1,47 @@
+galaxy_info:
+  author: cdh
+  description: install javascript dependencies for an app
+  company: Center for Digital Humanities @ Princeton
+
+  # If the issue tracker for your role is not on github, uncomment the
+  # next line and provide a value
+  # issue_tracker_url: http://example.com/issue/tracker
+
+  # Choose a valid license ID from https://spdx.org - some suggested licenses:
+  # - BSD-3-Clause (default)
+  # - MIT
+  # - GPL-2.0-or-later
+  # - GPL-3.0-only
+  # - Apache-2.0
+  # - CC-BY-4.0
+  license: Apache-2.0
+
+  min_ansible_version: 2.10
+
+  # If this a Container Enabled role, provide the minimum Ansible Container version.
+  # min_ansible_container_version:
+
+  #
+  # Provide a list of supported platforms, and for each platform a list of versions.
+  # If you don't wish to enumerate all versions for a particular platform, use 'all'.
+  # To view available platforms and versions (or releases), visit:
+  # https://galaxy.ansible.com/api/v1/platforms/
+  #
+  platforms:
+    - name: Ubuntu
+      versions:
+        - 18.04
+
+  galaxy_tags:
+    []
+    # List tags for your role here, one per line. A tag is a keyword that describes
+    # and categorizes the role. Users find roles by searching for tags. Be sure to
+    # remove the '[]' above, if you add tags to this list.
+    #
+    # NOTE: A tag is limited to a single word comprised of alphanumeric characters.
+    #       Maximum 20 tags per role.
+
+dependencies:
+  []
+  # List your role dependencies here, one per line. Be sure to remove the '[]' above,
+  # if you add dependencies to this list.

roles/build_npm/tasks/main.yml

@@ -7,8 +7,21 @@
 ---
 - name: npm configuration tasks
   block:
-    - name: Do npm install for dependencies
+
+    - name: ensure nodejs and package managers are installed
+      become: true
+      community.general.snap:
+        name: node
+        classic: true
+        channel: "{{ node_version }}"
+        state: present
+      when: ansible_distribution == "Ubuntu"
+
+    - name: install javascript dependencies with npm
+      become: true
+      become_user: "{{ deploy_user }}"
       npm:
-        path: '{{ deploy }}'
+        path: "{{ deploy }}"
+
   rescue:
     - include_tasks: roles/create_deployment/tasks/fail.yml