HealthChecks

<HEALTHCHECK I used in ECS (phtml) - CMD curl -f http://localhost:80 || exit 1>

<HEALTHCHECK I used in ECS (phtml) - CMD-SHELL, mysqladmin ping>  Don't forget to add: interval: 10s, timeout: 5s, retries: 10
** json for task definition in the bottom
                                                        sudo service apache2 stop
<PHP>
FROM php:7.2.2-apache
COPY ./mydirectory/ /var/www/html
RUN docker-php-ext-install mysqli

RUN apt-get update -y
RUN apt-get  install -y libcap2-bin

RUN setcap 'cap_net_bind_service=+ep' /usr/sbin/apache2
RUN getcap /usr/sbin/apache2
USER www-data


HEALTHCHECK CMD curl --fail http://18.218.210.112:8080/ || exit 1

//docker inspect --format='{{json .State.Health}}' <containerid>
====================================================================

<MySql>

version: '3.0'
services:
 mysql:
   image: mysql:5.7
   environment:
     MYSQL_ROOT_PASSWORD: password
   ports:
   - 3306:3306
   healthcheck:
     test: ["CMD-SHELL", 'mysqladmin ping']
     interval: 10s
     timeout: 5s
     retries: 10

https://stackoverflow.com/questions/53407287/docker-compose-wait-for-database-service-initialisation

--------------------------------------------------------------------------------
<Postgres>        I tried with version 2.1 and it works!!

version: "3"
services:
  postgress:
   image: postgres:11
   environment:
     POSTGRES_PASSWORD: postgres
   healthcheck:
     test: ["CMD-SHELL", "pg_isready -U postgres"]
     interval: 10s
     timeout: 5s
     retries: 5
   ports:
   - 5432:5432



   app:
     ...
     depends_on:
       postgres:
         condition: service_healthy



// psql -h 172.22.0.2 -p 5432 -U postgres
//  \l  - list all dbs
//  \c template1  -  connect db template1


https://dba.stackexchange.com/questions/1285/how-do-i-list-all-databases-and-tables-using-psql

--------------------------------------------------------------------------------
<Health check SWARM> Lecture 42

https://github.com/BretFisher/browncoat
https://hub.docker.com/r/bretfisher/browncoat



// docker pull bretfisher/browncoat
// docker service create --name firefly -p 80:80 --replicas 3 bretfisher/browncoat
// docker run --rm bretfisher/httping -i .1 -GsY http://18.218.210.112/healthz  (you run on the third node)
// docker events -f service=firefly    (you can run on the second node)
--------------------------------------------------------------------------------
<Health Check NGINX>   -Dockerfile-

vim dockerfile:

FROM nginx:1.17.7
RUN apt-get update && apt-get install -y wget
HEALTHCHECK CMD wget -q --method=HEAD localhost/system-status.txt

// docker build -t ng .
// docker run --name ng -p 80:80 ng

https://medium.com/better-programming/docker-healthchecks-eb744bfe3f3b