Docker卷必须为映射而非字符串错误排查（附docker-compose配置）

Let's break down what's causing this error and fix your docker-compose.yaml step by step:

1. The Root Cause of the Volume Error #

The error message points directly to the last line of your file: volumes:... — this is invalid YAML syntax for defining volumes. When using named volumes (like your db_data), you need to explicitly declare them in the top-level volumes section, even if you don't add any extra configuration for them.

2. Critical Typos Breaking File Parsing #

You've got two typos that are throwing off Docker Compose's ability to read the file correctly (which can also contribute to confusing error messages):

• serivces → should be services (missing the letter 'c')
• evironment (under the db service) → should be environment (missing the letter 'n')

Corrected docker-compose.yaml File #

Here's the fully fixed version of your Compose file:

version: '3.3'
services:
  db:
    image: mysql:5.7
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: password
      MYSQL_DATABASE: wordpress
      MYSQL_USER: wordpress
      MYSQL_PASSWORD: wordpress
  wordpress:
    depends_on:
      - db
    image: wordpress:latest
    ports:
      - "8000:80"
    volumes:
      - ./:/var/www/html
    restart: always
    environment:
      WORDPRESS_DB_HOST: db:3306
      WORDPRESS_DB_USER: wordpress
      WORDPRESS_DB_PASSWORD: wordpress
volumes:
  db_data:

Key Fixes Explained: #

• Valid Volume Declaration: Replaced volumes:... with volumes: db_data: — this tells Docker to create and manage the persistent db_data volume for MySQL.
• Fixed Service Key: services is the correct top-level key for defining your containers, so Docker can now properly read your db and wordpress service configurations.
• Fixed Environment Key: Correcting evironment to environment ensures the database's password and connection settings are applied properly.

After updating your file, run docker-compose up -d again — this should resolve the volume error and start your WordPress and MySQL containers successfully.

内容的提问来源于stack exchange，提问作者user818700