From db0e57251fa039be3ee349257dfe3061be0aa991 Mon Sep 17 00:00:00 2001
From: Eric Engstrom <eric.engstrom@gmail.com>
Date: Tue, 20 Apr 2021 16:47:20 -0500
Subject: [PATCH] Retry `docker` package installation at least once.

Why: when a previous installation was removed, but left behind service
configurations, and the docker service is disabled, package installation
will occasionally fail the first time.
---
 tasks/main.yml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tasks/main.yml b/tasks/main.yml
index dd90c22..b051620 100644
--- a/tasks/main.yml
+++ b/tasks/main.yml
@@ -9,6 +9,13 @@
   package:
     name: "{{ docker_package }}"
     state: "{{ docker_package_state }}"
+  # RETRY - when a previous installation was removed, but left behind service
+  # configurations, and the docker service is disabled, package installation
+  # will occasionally fail the first time, at least under Ubuntu 18.04.
+  retries: 2
+  delay: 2
+  register: install_result
+  until: install_result is not failed
   notify: restart docker
 
 - name: Ensure Docker is started and enabled at boot.