From 74013d82ab1e15f4e7e0f6c212a8047bc01eb3ab Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Carlos=20=C3=81lvaro?= <carlos@cdalvaro.io>
Date: Wed, 6 May 2020 07:13:03 +0200
Subject: [PATCH] feat: Add healthcheck for gitlab service

---
 README.md                                 | 47 ++++++++++++++++++++++-
 assets/build/install.sh                   | 10 +++++
 assets/runtime/config/gitlabhq/gitlab.yml |  1 +
 docker-compose.yml                        |  8 +++-
 4 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 6c00aaa1..9698b3e9 100644
--- a/README.md
+++ b/README.md
@@ -61,8 +61,9 @@
     - [Import Repositories](#import-repositories)
     - [Upgrading](#upgrading)
     - [Shell Access](#shell-access)
-- [Features](#features)
- - [Container Registry](docs/container_registry.md)
+- [Monitoring](#monitoring)
+    - [Health Check](#health-check)
+- [Container Registry](docs/container_registry.md)
 - [References](#references)
 
 # Introduction
@@ -1333,6 +1334,48 @@ For debugging and maintenance purposes you may want access the containers shell.
 docker exec -it gitlab bash
 ```
 
+# Monitoring
+
+You can monitor your GitLab instance status as described in the [official documentation](https://docs.gitlab.com/ee/user/admin_area/monitoring/health_check.html), for example:
+
+```bash
+curl 'https://gitlab.example.com/-/liveness'
+```
+
+On success, the endpoint will return a `200` HTTP status code, and a response like below.
+
+```bash
+{
+   "status": "ok"
+}
+```
+
+To do that you will need to set the environment variable `GITLAB_MONITORING_IP_WHITELIST` to allow your IP or subnet to make requests to your GitLab instance.
+
+## Health Check
+
+You can also set your `docker-compose.yml` [healthcheck](https://docs.docker.com/compose/compose-file/compose-file-v2/#healthcheck) configuration to make periodic checks:
+
+```yml
+version: '2.3'
+
+services:
+  gitlab:
+    image: sameersbn/gitlab:12.7.7
+    healthcheck:
+      test: ["CMD", "/usr/local/sbin/healthcheck"]
+      interval: 1m
+      timeout: 5s
+      retries: 5
+      start_period: 2m
+```
+
+Then you will be able to consult the healthcheck log by executing:
+
+```bash
+docker inspect --format "{{json .State.Health }}" $(docker-compose ps -q gitlab) | jq
+```
+
 # References
 
 * https://github.com/gitlabhq/gitlabhq
diff --git a/assets/build/install.sh b/assets/build/install.sh
index 8b7fbe02..9127178b 100755
--- a/assets/build/install.sh
+++ b/assets/build/install.sh
@@ -426,6 +426,16 @@ programs=sshd,nginx,mail_room,cron
 priority=20
 EOF
 
+# configure healthcheck script
+## https://docs.gitlab.com/ee/user/admin_area/monitoring/health_check.html
+cat > /usr/local/sbin/healthcheck <<EOF
+#!/bin/bash
+url=http://localhost/-/liveness
+curl -s \$url
+[[ "\$(curl -s -o /dev/null -I -w '%{http_code}' \$url)" == "200" ]]
+EOF
+chmod +x /usr/local/sbin/healthcheck
+
 # purge build dependencies and cleanup apt
 DEBIAN_FRONTEND=noninteractive apt-get purge -y --auto-remove ${BUILD_DEPENDENCIES}
 rm -rf /var/lib/apt/lists/*
diff --git a/assets/runtime/config/gitlabhq/gitlab.yml b/assets/runtime/config/gitlabhq/gitlab.yml
index 4a6bff9f..7f9b6140 100644
--- a/assets/runtime/config/gitlabhq/gitlab.yml
+++ b/assets/runtime/config/gitlabhq/gitlab.yml
@@ -1149,6 +1149,7 @@ production: &base
     # puma_sampler_interval: 5
     # IP whitelist to access monitoring endpoints
     ip_whitelist:
+      - 127.0.0.0/8
       - {{GITLAB_MONITORING_IP_WHITELIST}}
 
     # Sidekiq exporter is webserver built in to Sidekiq to expose Prometheus metrics
diff --git a/docker-compose.yml b/docker-compose.yml
index b15e62b9..3089c867 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,4 +1,4 @@
-version: '2'
+version: '2.3'
 
 services:
   redis:
@@ -31,6 +31,12 @@ services:
     - "10022:22"
     volumes:
     - gitlab-data:/home/git/data:Z
+    healthcheck:
+      test: ["CMD", "/usr/local/sbin/healthcheck"]
+      interval: 5m
+      timeout: 10s
+      retries: 3
+      start_period: 5m
     environment:
     - DEBUG=false