From 941e95ace6efdcf405dc42efab3f028122457e63 Mon Sep 17 00:00:00 2001 From: thomasabishop Date: Tue, 26 Mar 2024 14:20:03 +0000 Subject: [PATCH] Autosave: 2024-03-26 14:20:03 --- ...ocker_compose_and_Dockerfile_difference.md | 75 +++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 zk/Docker_compose_and_Dockerfile_difference.md diff --git a/zk/Docker_compose_and_Dockerfile_difference.md b/zk/Docker_compose_and_Dockerfile_difference.md new file mode 100644 index 0000000..f1cc515 --- /dev/null +++ b/zk/Docker_compose_and_Dockerfile_difference.md @@ -0,0 +1,75 @@ +--- +id: fw56 +title: Docker compose and Dockerfile difference +tags: [] +created: Tuesday, March 26, 2024 +--- + +# Docker compose and Dockerfile difference + +### Key Differences + +- **Scope**: A `Dockerfile` is for building a single Docker image, while + `docker-compose.yml` is for orchestrating multiple containers (that might be + built from `Dockerfiles`) to work together as a unified application. +- **Use Case**: A `Dockerfile` is necessary when you need to create a custom + image. In contrast, `docker-compose.yml` is used when you want to deploy and + manage an application that consists of multiple containers. +- **Command**: You build an image from a `Dockerfile` using `docker build`. You + start the application defined by `docker-compose.yml` using + `docker-compose up`. + +### Dockerfile + +- **Purpose**: A `Dockerfile` is a text document that contains all the commands + a user could call on the command line to assemble an image. It automates the + process of creating Docker images by specifying a sequence of steps and + configurations such as setting environment variables, installing software, and + copying files from the local directory into the image. +- **Functionality**: It is essentially a blueprint for building Docker images. + You define the base image, software packages, scripts, files, environment + variables, and other components you need in your Docker image. +- **Usage**: You use a `Dockerfile` when you need to create a custom Docker + image based on your application's specific dependencies and runtime + environment. After defining your `Dockerfile`, you use the `docker build` + command to create an image. + + Example structure of a Dockerfile: + + ```Dockerfile + FROM python:3.8 + WORKDIR /app + COPY . /app + RUN pip install -r requirements.txt + CMD ["python", "./my_script.py"] + ``` + +### docker-compose.yml + +- **Purpose**: A `docker-compose.yml` file is used to define and run + multi-container Docker applications. With a single command, you can configure + all of your application's services, networks, and volumes in this YAML file + and bring everything up or down. +- **Functionality**: It simplifies the deployment and management of application + components that are meant to run in separate containers while still needing to + communicate or work together. For example, a web application might consist of + a web server, a database, and a caching system, each running in its container. +- **Usage**: `docker-compose` is used for defining and running complex + applications with Docker. Instead of using lengthy `docker run` commands with + many flags, you write a `docker-compose.yml` file and use `docker-compose up` + to start the application. + + Example structure of a docker-compose.yml file: + + ```yaml + version: "3" + services: + web: + build: . + ports: + - "5000:5000" + db: + image: postgres + volumes: + - ./data:/var/lib/postgresql/data + ```