Reading ".env" in Vagrantfile to provide environment for docker-compose

Vagrantfile

# -*- mode: ruby -*-
# vi: set ft=ruby :

Vagrant.configure(2) do |config|
  if !Vagrant.has_plugin?("vagrant-docker-compose")
    print "  WARN: Missing plugin 'vagrant-docker-compose'.\n"
    print "  Use 'vagrant plugin install vagrant-docker-compose' to install.\n"
  end

  compose_env = Hash.new
  if File.file?('.env')
      # read lines "var=value" into hash
      compose_env = Hash[*File.read('.env').split(/[=\n]+/)]
      # ignore keys (lines) starting with #
      compose_env.delete_if { |key, value| key.to_s.match(/^#.*/) }
  end

  config.vm.provision :docker
  config.vm.provision :docker_compose,
    project_name: "docker-vagrant",
    yml: "/vagrant/docker-compose.yml",
    env: compose_env,
    run: "always"
end

I try my best to solve ,but it can’t be finished.
`==> default: bash: line 4: =: command not found
The following SSH command responded with a non-zero exit status.
Vagrant assumes that this means the command failed!

SOURCE_DIR=./www ='' DATA_DIR=./data TZ=Asia/Shanghai CONTAINER_PACKAGE_URL=mirrors.aliyun.com ALPINE_VERSION=3.12 NGINX_VERSION=1.19.1-alpine NGINX_HTTP_HOST_PORT=80 NGINX_HTTPS_HOST_PORT=443 NGINX_CONFD_DIR=./services/nginx/conf.d NGINX_CONF_FILE=./services/nginx/nginx.conf NGINX_FASTCGI_PHP_CONF=./services/nginx/fastcgi-php.conf NGINX_FASTCGI_PARAMS=./services/nginx/fastcgi_params NGINX_SSL_CERTIFICATE_DIR=./services/nginx/ssl NGINX_LOG_DIR=./logs/nginx NGINX_INSTALL_APPS='' PHP_VERSION=7.1.33 PHP_PHP_CONF_FILE=./services/php/php.ini PHP_FPM_CONF_FILE=./services/php/php-fpm.conf PHP_LOG_DIR=./logs/php PHP_EXTENSIONS=pdo_mysql,mysqli,mbstring,gd,curl,opcache,amqp,bcmath,bz2,calendar,exif,gettext,igbinary,mcrypt,mongodb,pcntl,pdo_pgsql,pgsql,rdkafka,redis,shmop,soap,sockets,ssh2,swoole,sysvmsg,sysvsem,sysvshm,wddx,xsl,yaf,zip MYSQL5_VERSION=5.7.28 MYSQL5_HOST_PORT=3305 MYSQL5_ROOT_PASSWORD=123456 MYSQL5_CONF_FILE=./services/mysql5/mysql.cnf REDIS_VERSION=5.0.3-alpine REDIS_HOST_PORT=6379 REDIS_CONF_FILE=./services/redis/redis.conf NODE_VERSION=10.16.1-alpine /usr/local/bin/docker-compose-1.29.2 -f "/vagrant/docker-compose.yml" up -d

Stdout from the command:

Stderr from the command:

bash: line 4: =: command not found`