Ruby on Rails 6 + Docker = Webpacker::Manifest::MissingEntry

Question

试图将我的Rails应用程序作为Docker容器运行，但在打开页面时出现以下错误：

Webpacker can't find application in /app/public/packs/manifest.json. Possible causes:
1. You want to set webpacker.yml value of compile to true for your environment
unless you are using the `webpack -w` or the webpack-dev-server.
2. webpack has not yet re-run to reflect updates.
3. You have misconfigured Webpacker's config/webpacker.yml file.
4. Your webpack configuration is not creating a manifest.
Your manifest contains:
{
}

当我简单地使用rails s运行应用程序时，它运行良好，并且创建了public/packs文件夹。在日志中还有

/usr/local/bundle/gems/webpacker-4.2.0/lib/webpacker/runner.rb:13:in ``': No such file or directory - yarn (Errno::ENOENT)

错误，尽管我检查了容器yarn-v显示已安装yarn。

Dockerfile

FROM ruby:2.6.3
RUN apt-get update -qq 
&& curl -sL https://deb.nodesource.com/setup_12.x  | bash - 
&& apt-get install -y nodejs 
&& curl -o- -L https://yarnpkg.com/install.sh | bash
RUN mkdir /app
WORKDIR /app
COPY Gemfile /app/Gemfile
COPY Gemfile.lock /app/Gemfile.lock
RUN bundle install
COPY . /app
# Add a script to be executed every time the container starts.
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000
# Start the main process.
CMD ["rails", "server", "-b", "0.0.0.0"]

docker-compose.yml

version: '3'
services:
webpacker:
build: .
env_file:
- '.env.docker'
command: ./bin/webpack-dev-server
volumes:
- .:/app
ports:
- '3035:3035'
web:
build: .
command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
volumes:
- .:/app
ports:
- "3000:3000"

.env.docker

NODE_ENV=development
RAILS_ENV=development
WEBPACKER_DEV_SERVER_HOST=0.0.0.0

Answer 1

按照以下步骤操作。

i( 码头工人组成run #{rails_app_name}纱线

然后再次使用构建您的项目

ii(docker-compose build #{rails_app_name}

iii(docker-compose up

参考：[1] ：https://github.com/rails/webpacker/issues/1568