Course 31 - Dive Into Docker | Episode 9: Orchestrating Multi-Container Web Applications with Docker Compose

In this lesson, you’ll learn about: Docker Compose, multi-container apps, and service orchestration1. What is Docker Compose?Docker Compose is a tool used to:DefineRunManagemulti-container applications using a single command👉 Instead of long docker run commands, you describe everything in one file2. The docker-compose.yml FileCore configuration file written in YAMLUses version 3 syntaxExample structure:version: "3" services: web: build: . redis: image: redisDefines:Services (containers)NetworksVolumes3. Defining ServicesEach service represents a containerExample:Web app (custom build)Redis (prebuilt image)🔹 Build vs Imagebuild: → build from local Dockerfileimage: → pull from registry (e.g., Docker Hub)web: build: . redis: image: redis 4. Port Mappingports: - "5000:5000"Format:host_port : container_port👉 Allows access from your browser (localhost)5. Volumes (Data Management)🔹 Host-Mounted Volumevolumes: - .:/appSyncs local files with containerIdeal for development🔹 Named Volumevolumes: - redis-data:/data volumes: redis-data:Persistent storageManaged by Docker6. Managing Service Dependenciesdepends_on: - redisEnsures:Redis starts before the web app👉 Important for backend-dependent services7. Environment Variables with .envStore sensitive or dynamic values:COMPOSE_PROJECT_NAME=myapp Benefits:Cleaner configAvoid hardcodingEasy to manage across environments🔹 COMPOSE_PROJECT_NAMEDefines a custom project namePrevents conflicts between projects👉 Useful when running multiple apps on the same machine8. Running Everything with One Commanddocker-compose upBuilds imagesCreates containersStarts all services9. Why Docker Compose MattersSimplifies complex setupsReduces human errorMakes projects:ReproducibleShareableScalableKey TakeawaysDocker Compose = multi-container management made easydocker-compose.yml = your infrastructure blueprintSupports:ServicesVolumesNetworksEnvironment variablesOne command replaces dozens of manual stepsYou can listen and download our episodes for free on more than 10 different platforms:https://linktr.ee/cybercode_academy