Ansible playbook for installing Zcash dependencies and Buildbot worker

contrib/ci-workers/unix.yml

@@ -0,0 +1,56 @@
+---
+- name: Configure a Buildbot worker for Zcash CI
+  hosts: zcash-ci-worker-unix
+  become: true
+  gather_facts: False
+
+  pre_tasks:
+    - set_fact:
+        python_raw: "test -e /usr/bin/python || test -e /usr/bin/python2 || test -e /usr/bin/python2.7 || test -e /usr/local/bin/python2.7 || (test -e /usr/bin/apt && apt -qqy update && apt install -qqy python) || (test -e /usr/bin/dnf && dnf install -qqy python2) || (test -e /usr/sbin/pkg && pkg install -qqy python2)"
+    - name: Install Python 2 for Ansible and Buildbot [bash]
+      raw: bash -c "'{{ python_raw }}'"
+      ignore_errors: true
+      register: output
+      changed_when:
+        - output.stdout != ""
+        - output.stdout != "\r\n"
+    - name: Install Python 2 for Ansible and Buildbot [tcsh]
+      raw: tcsh -c "{{ python_raw }}"
+      ignore_errors: true
+      register: output
+      changed_when:
+        - output.stdout != ""
+        - output.stdout != "\r\n"
+    - name: Gathering Facts
+      setup:
+
+  tasks:
+    - name: Get default dependencies
+      include_vars: "vars/default.yml"
+
+    - name: Get dependencies for distribution
+      include_vars: "{{ item }}"
+      with_first_found:
+        - files:
+            - "vars/{{ ansible_distribution }}-{{ ansible_distribution_version }}.yml"
+            - "vars/{{ ansible_distribution }}-{{ ansible_distribution_major_version | int }}.yml"
+            - "vars/{{ ansible_distribution }}.yml"
+            - "vars/{{ ansible_os_family }}.yml"
+          skip: true
+
+    - name: Collate dependencies
+      set_fact:
+        package_deps: "{{ buildbot_deps + fetch_deps + conf_deps + build_deps + link_deps + dist_deps }}"
+        python_modules: "{{ buildbot_modules + rpc_test_modules }}"
+
+    - name: Install required packages
+      package:
+        name: "{{ item }}"
+        state: present
+      with_items: "{{ package_deps }}"
+
+    - name: Install required Python modules
+      pip:
+        name: "{{ item }}"
+        state: latest
+      with_items: "{{ python_modules }}"