From 03a0bef7b6199fba3922b78b0eb877b73fff7b00 Mon Sep 17 00:00:00 2001
From: "James E. Blair" <jim@acmegating.com>
Date: Mon, 7 Feb 2022 09:41:38 -0800
Subject: [PATCH] Add the start of a Zuul rolling restart playbook

This handles rolling the mergers and executors, but not yet
the schedulers.

Also, it does the executors in complete batches of 6, but could be
improved to stop 6 and then do each of the next as the first ones
complete.

Change-Id: I2dca104194c2f129b68dcef7721d7d08cb987c46
---
 .../roles/zuul-executor/tasks/graceful.yaml   | 18 +++++++++++++++
 .../roles/zuul-merger/tasks/graceful.yaml     | 18 +++++++++++++++
 playbooks/zuul_rolling_restart.yaml           | 23 +++++++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100644 playbooks/roles/zuul-executor/tasks/graceful.yaml
 create mode 100644 playbooks/roles/zuul-merger/tasks/graceful.yaml
 create mode 100644 playbooks/zuul_rolling_restart.yaml

diff --git a/playbooks/roles/zuul-executor/tasks/graceful.yaml b/playbooks/roles/zuul-executor/tasks/graceful.yaml
new file mode 100644
index 0000000000..503253a9e0
--- /dev/null
+++ b/playbooks/roles/zuul-executor/tasks/graceful.yaml
@@ -0,0 +1,18 @@
+- name: Gracefully stop Zuul Executor
+  shell:
+    cmd: docker-compose exec executor zuul-executor graceful
+    chdir: /etc/zuul-executor
+  become: true
+  become_user: root
+- name: Wait for Zuul Executor to stop
+  shell:
+    cmd: docker-compose ps -q | xargs docker wait
+    chdir: /etc/zuul-executor
+  become: true
+  become_user: root
+- name: Remove Zuul Executor containers
+  shell:
+    cmd: docker-compose down
+    chdir: /etc/zuul-executor
+  become: true
+  become_user: root
diff --git a/playbooks/roles/zuul-merger/tasks/graceful.yaml b/playbooks/roles/zuul-merger/tasks/graceful.yaml
new file mode 100644
index 0000000000..37da7ac8d0
--- /dev/null
+++ b/playbooks/roles/zuul-merger/tasks/graceful.yaml
@@ -0,0 +1,18 @@
+- name: Gracefully stop Zuul Merger
+  shell:
+    cmd: docker-compose exec merger zuul-merger stop
+    chdir: /etc/zuul-merger
+  become: true
+  become_user: root
+- name: Wait for Zuul Merger to stop
+  shell:
+    cmd: docker-compose ps -q | xargs docker wait
+    chdir: /etc/zuul-merger
+  become: true
+  become_user: root
+- name: Down Zuul Merger containers
+  shell:
+    cmd: docker-compose down
+    chdir: /etc/zuul-merger
+  become: true
+  become_user: root
diff --git a/playbooks/zuul_rolling_restart.yaml b/playbooks/zuul_rolling_restart.yaml
new file mode 100644
index 0000000000..ffce54f482
--- /dev/null
+++ b/playbooks/zuul_rolling_restart.yaml
@@ -0,0 +1,23 @@
+# Run this with "-f 20"
+
+- hosts: 'zuul-merger:!disabled'
+  tasks:
+    - include_role:
+        name: zuul-merger
+        tasks_from: graceful
+
+- hosts: 'zuul-executor:!disabled'
+  serial: 6
+  tasks:
+    - include_role:
+        name: zuul-executor
+        tasks_from: graceful
+    - include_role:
+        name: zuul-executor
+        tasks_from: start
+
+- hosts: 'zuul-merger:!disabled'
+  tasks:
+    - include_role:
+        name: zuul-merger
+        tasks_from: start