From 80cfb2a93ea0f36d1db1545e586c7e3946cf79ce Mon Sep 17 00:00:00 2001
From: Dan Arnfield <dan@arnfield.com>
Date: Mon, 18 Nov 2019 11:20:01 -0600
Subject: [PATCH] Add matrix_docker_installation_enabled

---
 roles/matrix-base/defaults/main.yml                  | 4 ++++
 roles/matrix-base/tasks/server_base/setup.yml        | 6 ++++++
 roles/matrix-base/tasks/server_base/setup_centos.yml | 3 +++
 roles/matrix-base/tasks/server_base/setup_debian.yml | 3 +++
 4 files changed, 16 insertions(+)

diff --git a/roles/matrix-base/defaults/main.yml b/roles/matrix-base/defaults/main.yml
index fc119a44..a8d27271 100644
--- a/roles/matrix-base/defaults/main.yml
+++ b/roles/matrix-base/defaults/main.yml
@@ -42,6 +42,10 @@ matrix_docker_network: "matrix"
 # matrix domain (`matrix_server_fqn_matrix`).
 matrix_well_known_matrix_server_enabled: true
 
+# Controls whether docker is automatically installed.
+# If you change this to false you must install and update docker manually.
+matrix_docker_installation_enabled: true
+
 # Variables to Control which parts of our roles run.
 run_postgres_import: true
 run_postgres_upgrade: true
diff --git a/roles/matrix-base/tasks/server_base/setup.yml b/roles/matrix-base/tasks/server_base/setup.yml
index 45feb152..9ca2ce2e 100644
--- a/roles/matrix-base/tasks/server_base/setup.yml
+++ b/roles/matrix-base/tasks/server_base/setup.yml
@@ -1,5 +1,11 @@
 ---
 
+- name: Gather package facts
+  package_facts:
+
+- set_fact:
+    run_docker_installation: "{{ matrix_docker_installation_enabled|bool and 'docker.io' not in ansible_facts.packages }}"
+
 - include_tasks: "{{ role_path }}/tasks/server_base/setup_centos.yml"
   when: ansible_distribution == 'CentOS'
 
diff --git a/roles/matrix-base/tasks/server_base/setup_centos.yml b/roles/matrix-base/tasks/server_base/setup_centos.yml
index 1c891ab1..e7979704 100644
--- a/roles/matrix-base/tasks/server_base/setup_centos.yml
+++ b/roles/matrix-base/tasks/server_base/setup_centos.yml
@@ -9,11 +9,13 @@
     mode: 0644
   with_items:
     - docker-ce.repo
+  when: run_docker_installation|bool
 
 - name: Ensure Docker's RPM key is trusted
   rpm_key:
     state: present
     key: https://download.docker.com/linux/centos/gpg
+  when: run_docker_installation|bool
 
 - name: Ensure yum packages are installed
   yum:
@@ -31,3 +33,4 @@
       - docker-ce
     state: latest
     update_cache: yes
+  when: run_docker_installation|bool
diff --git a/roles/matrix-base/tasks/server_base/setup_debian.yml b/roles/matrix-base/tasks/server_base/setup_debian.yml
index d4b16968..6705366f 100644
--- a/roles/matrix-base/tasks/server_base/setup_debian.yml
+++ b/roles/matrix-base/tasks/server_base/setup_debian.yml
@@ -15,12 +15,14 @@
     state: present
   register: add_repository_key
   ignore_errors: true
+  when: run_docker_installation|bool
 
 - name: Ensure Docker repository is enabled
   apt_repository:
     repo: "deb [arch=amd64] https://download.docker.com/linux/{{ ansible_distribution|lower }} {{ ansible_distribution_release }} stable"
     state: present
     update_cache: yes
+  when: run_docker_installation|bool
 
 - name: Ensure APT packages are installed
   apt:
@@ -38,3 +40,4 @@
       - docker-ce
     state: latest
     update_cache: yes
+  when: run_docker_installation|bool