iQuest Keyboards & Mice - Brașov - 2018

Table of Contents

• Description
• Presentation Slides
• References
• Running the Application

Description

This repo contains the resources used during "How to Control Service Startup Order in Docker Compose" presentation at the Keyboards & Mice iQuest public event, which took place in Brașov on June 6th, 2018.

This presentation is based on this article, but while the latter shows a Java console application fetching data from a MySQL database, the former uses a .NET Core console application fetching data from a PostgreSQL database.

Presentation Slides

SlideShare: https://www.slideshare.net/satrapu/how-to-control-service-startup-order-in-docker-compose

References

• Docker
  • Home
  • Documentation
  • HEALTHCHECK instruction
  • Multi-stage builds
  • Daemon socket option
  • Understanding the Security Risks of Running Docker Containers: Don't Lose Your Sock(et)s
• Docker Compose
  • Home
  • Documentation
  • Compatibility matrix
  • Compose file format reference
  • Environment variables in Compose
  • Control startup order in Compose
  • Compose file depends_on directive
  • Depends_on in version3
  • Docker-compose bind mount docker.sock not a valid Windows path
• Docker Engine API
  • Home
  • API version history
• curl
  • Home
  • Documentation
  • unix-socket option
  • Running curl from Docker
• jq
  • Home
  • Documentation
  • Playground
• .NET Core
  • Home
  • Documentation
  • Docker images
  • Using .NET Core in Visual Studio Code
  • PostgreSQL ADO.NET driver
    • Home
    • Documentation
    • NuGet package
• PostgreSQL
  • Home
  • Documentation
  • Docker image
  • Client Docker image
  • pg_isready
• Alpine Linux
  • Home
  • Packages for v3.7, x64
• Symbolic links on Windows
  • The Complete Guide to Creating Symbolic Links (aka Symlinks) on Windows
  • Create a hard-link from /dotnet-core-with-docker/sources to /dotnet-core-with-docker/compose/service-healthy folder:

  # PowerShell
  cd .\dotnet-core-with-docker\compose\service-healthy
  cmd /c mklink /J .\sources .\..\..\sources

Running the Application

• Clone this repo

git clone https://github.com/satrapu/iquest-keyboards-and-mice-brasov-2018.git
cd ./iquest-keyboards-and-mice-brasov-2018

• Start services

  • Using depends_on, condition and service_healthy:

  # Windows - PowerShell console run as admin
  cd .\compose\service-healthy `
  ;cmd /c mklink /J .\sources .\..\..\sources `
  ;docker-compose down --rmi local `
  ;docker-compose build `
  ;docker-compose up app

  # Linux - Bash
  cd ./compose/service-healthy \
  && mkdir ./sources && cp ../../sources/* sources \
  && docker-compose down --rmi local \
  && docker-compose build \
  && docker-compose up app

  • Using Docker Engine API

  # Windows - PowerShell console run as admin
  cd .\compose\docker-engine-api `
  ;cmd /c mklink /J .\sources .\..\..\sources `
  ;$Env:COMPOSE_CONVERT_WINDOWS_PATHS=1 `
  ;docker-compose down --rmi local `
  ;docker-compose build `
  ;docker-compose up app

  # Linux - Bash
  cd ./compose/docker-engine-api \
  && mkdir ./sources && cp ../../sources/* sources \
  && docker-compose down --rmi local \
  && docker-compose build \
  && docker-compose up app

  • Using port checking++

  # Windows - PowerShell console run as admin
  cd .\compose\port-checking++ `
  ;cmd /c mklink /J .\sources .\..\..\sources `
  ;docker-compose down --rmi local `
  ;docker-compose build `
  ;docker-compose up --exit-code-from check_db_connectivity check_db_connectivity `
  ;if ($LASTEXITCODE -eq 0) { docker-compose up app } `
  else { echo "ERROR: Failed to start service due to one of its dependencies!" }

  # Linux - Bash
  cd ./compose/port-checking++ \
  && mkdir ./sources && cp ../../sources/* sources \
  && docker-compose down --rmi local \
  && docker-compose build \
  && docker-compose up --exit-code-from check_db_connectivity check_db_connectivity \
  && if [ $? -eq 0 ]; then docker-compose up app; else echo 'ERROR: Failed to start service due to one of its dependencies!'; fi