Detailed explanation of immich configuration file

# Specify the version of Docker Compose file to 3.8version: "3.8"

# Define the name of the project as immichname: immich

# Define multiple servicesservices:
  # Define a service name immich-server  immich-server:
    # Set the name of the container to immich_server    container_name: immich_server
    # Pull the immich-server image from GitHub Container Registry. The version is specified by the IMMICH_VERSION environment variable, and the default is release    image: /immich-app/immich-server:${IMMICH_VERSION:-release}
    # Commands executed after the container is started    command: [ "", "immich" ]
    # Specify the mounted volume    volumes:
      # Mount the host's UPLOAD_LOCATION directory to /usr/src/app/upload of the container      - ${UPLOAD_LOCATION}:/usr/src/app/upload
      # Mount the host's /etc/localtime into the container and synchronize the time in a read-only manner      - /etc/localtime:/etc/localtime:ro
    # Specify environment variable file    env_file:
      # Use the .env file in the current directory      - .env
    # Specify port mapping    ports:
      # Map the container's port 3001 to the host's port 2283      - 2283:3001
    # Define service dependencies    depends_on:
      # immich-server depends on redis and database services      - redis
      - database
    # Set the container's restart policy to always restart    restart: always

  # Define another service name immich-microservices  immich-microservices:
    # Set the name of the container to immich_microservices    container_name: immich_microservices
    # Use the same mirroring and versioning policies    image: /immich-app/immich-server:${IMMICH_VERSION:-release}
    # Command to start microservices    command: [ "", "microservices" ]
    # Also specify the mounted volume    volumes:
      - ${UPLOAD_LOCATION}:/usr/src/app/upload
      - /etc/localtime:/etc/localtime:ro
    # Use the same environment variable file    env_file:
      - .env
    # Also relies on redis and database services    depends_on:
      - redis
      - database
    # Also set to always restart    restart: always

# The following is the part that defines the volumes to specify the required Docker volumesvolumes:
  # Define a volume name pgdata to persist PostgreSQL database data  pgdata:
  # Define a volume named model-cache, which is used to cache machine learning model data  model-cache:

# You can find all supported environment variables documentation in this URL: /docs/install/environment-variables# The above line is a comment that illustrates how to find the official documentation about all supported environment variables.
# The file you upload will be stored in this locationUPLOAD_LOCATION=./library
# Set the `UPLOAD_LOCATION` environment variable to define the storage location of uploaded files.  This is set to the `library` folder in the current directory.
# Immich version used.  You can pin it to a specific version, such as "v1.71.0"IMMICH_VERSION=release
# Set the `IMMICH_VERSION` environment variable to specify the version Immich is used.  Set to `release` here, which means that the latest release version will be used.
# Connection password for Postgres.  You should change it to a random passwordDB_PASSWORD=postgres
# Set the `DB_PASSWORD` environment variable to define the password to connect to the PostgreSQL database.  The default setting is `postgres`, and it is recommended to change to a more secure password.
# The following line does not need to be changed###################################################################################
# The above line is a comment, indicating that the following environment variables usually do not need to be modified.
DB_HOSTNAME=immich_postgres
# Set the `DB_HOSTNAME` environment variable and specify the host name of the PostgreSQL database service.  Here is the service name `immich_postgres` defined in the file.
DB_USERNAME=postgres
# Set the `DB_USERNAME` environment variable to define the user name that connects to the PostgreSQL database.  The default setting is `postgres`.
DB_DATABASE_NAME=immich
# Set the `DB_DATABASE_NAME` environment variable and specify the name of the PostgreSQL database.  Here is set to `immich`.
REDIS_HOSTNAME=immich_redis
# Set the `REDIS_HOSTNAME` environment variable and specify the host name of the Redis service.  Here is the service name `immich_redis` defined in the file.