容器化 Node.js 應用程式

先決條件

您已安裝最新版本的 Docker Desktop。
您擁有一個 git 客戶端。本節中的示例使用基於命令列的 git 客戶端，但您可以使用任何客戶端。

概述

本節將引導您完成容器化和執行 Node.js 應用程式的過程。

獲取示例應用程式

克隆示例應用程式以用於本指南。開啟終端，更改目錄到您要工作的目錄，並執行以下命令克隆儲存庫

$ git clone https://github.com/docker/docker-nodejs-sample

初始化 Docker 資源

現在您已經擁有了應用程式，可以建立必要的 Docker 資源來容器化您的應用程式。您可以使用 Docker Desktop 內建的 Docker Init 功能來幫助簡化流程，也可以手動建立資源。

在 docker-nodejs-sample 目錄中，在終端中執行 docker init 命令。docker init 提供了一些預設配置，但您需要回答一些有關您的應用程式的問題。請參考以下示例以回答 docker init 中的提示，並使用相同的答案來回答您的提示。

$ docker init
Welcome to the Docker Init CLI!

This utility will walk you through creating the following files with sensible defaults for your project:
  - .dockerignore
  - Dockerfile
  - compose.yaml
  - README.Docker.md

Let's get started!

? What application platform does your project use? Node
? What version of Node do you want to use? 18.0.0
? Which package manager do you want to use? npm
? What command do you want to use to start the app: node src/index.js
? What port does your server listen on? 3000

如果您沒有安裝 Docker Desktop 或更喜歡手動建立資源，您可以在專案目錄中建立以下檔案。

建立一個名為 Dockerfile 的檔案，內容如下。

Dockerfile

# syntax=docker/dockerfile:1

# Comments are provided throughout this file to help you get started.
# If you need more help, visit the Dockerfile reference guide at
# https://docs.docker.net.tw/go/dockerfile-reference/

# Want to help us make this template better? Share your feedback here: https://forms.gle/ybq9Krt8jtBL3iCk7

ARG NODE_VERSION=18.0.0

FROM node:${NODE_VERSION}-alpine

# Use production node environment by default.
ENV NODE_ENV production


WORKDIR /usr/src/app

# Download dependencies as a separate step to take advantage of Docker's caching.
# Leverage a cache mount to /root/.npm to speed up subsequent builds.
# Leverage a bind mounts to package.json and package-lock.json to avoid having to copy them into
# into this layer.
RUN --mount=type=bind,source=package.json,target=package.json \
    --mount=type=bind,source=package-lock.json,target=package-lock.json \
    --mount=type=cache,target=/root/.npm \
    npm ci --omit=dev

# Run the application as a non-root user.
USER node

# Copy the rest of the source files into the image.
COPY . .

# Expose the port that the application listens on.
EXPOSE 3000

# Run the application.
CMD node src/index.js

建立一個名為 compose.yaml 的檔案，內容如下。

compose.yaml

# Comments are provided throughout this file to help you get started.
# If you need more help, visit the Docker Compose reference guide at
# https://docs.docker.net.tw/go/compose-spec-reference/

# Here the instructions define your application as a service called "server".
# This service is built from the Dockerfile in the current directory.
# You can add other services your application may depend on here, such as a
# database or a cache. For examples, see the Awesome Compose repository:
# https://github.com/docker/awesome-compose
services:
  server:
    build:
      context: .
    environment:
      NODE_ENV: production
    ports:
      - 3000:3000

# The commented out section below is an example of how to define a PostgreSQL
# database that your application can use. `depends_on` tells Docker Compose to
# start the database before your application. The `db-data` volume persists the
# database data between container restarts. The `db-password` secret is used
# to set the database password. You must create `db/password.txt` and add
# a password of your choosing to it before running `docker-compose up`.
#     depends_on:
#       db:
#         condition: service_healthy
#   db:
#     image: postgres
#     restart: always
#     user: postgres
#     secrets:
#       - db-password
#     volumes:
#       - db-data:/var/lib/postgresql/data
#     environment:
#       - POSTGRES_DB=example
#       - POSTGRES_PASSWORD_FILE=/run/secrets/db-password
#     expose:
#       - 5432
#     healthcheck:
#       test: [ "CMD", "pg_isready" ]
#       interval: 10s
#       timeout: 5s
#       retries: 5
# volumes:
#   db-data:
# secrets:
#   db-password:
#     file: db/password.txt

建立一個名為 .dockerignore 的檔案，內容如下。

.dockerignore

# Include any files or directories that you don't want to be copied to your
# container here (e.g., local build artifacts, temporary files, etc.).
#
# For more help, visit the .dockerignore file reference guide at
# https://docs.docker.net.tw/go/build-context-dockerignore/

**/.classpath
**/.dockerignore
**/.env
**/.git
**/.gitignore
**/.project
**/.settings
**/.toolstarget
**/.vs
**/.vscode
**/.next
**/.cache
**/*.*proj.user
**/*.dbmdl
**/*.jfm
**/charts
**/docker-compose*
**/compose.y*ml
**/Dockerfile*
**/node_modules
**/npm-debug.log
**/obj
**/secrets.dev.yaml
**/values.dev.yaml
**/build
**/dist
LICENSE
README.md

現在您應該至少在 docker-nodejs-sample 目錄中擁有以下內容。

├── docker-nodejs-sample/
│ ├── spec/
│ ├── src/
│ ├── .dockerignore
│ ├── .gitignore
│ ├── compose.yaml
│ ├── Dockerfile
│ ├── package-lock.json
│ ├── package.json
│ └── README.md

要了解有關這些檔案的更多資訊，請參閱以下內容