Support NGINX_ENABLED Environment Variable

[comfuture]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

When using Docker to run Dify, an Nginx container is launched. This container provides a reverse proxy for API and web, and, depending on the options, it supports HTTPS and certbot certificate renewal, making it convenient.
However, by default, EXPOSE_NGINX_PORT and EXPOSE_NGINX_SSL_PORT are set to 80 and 443 respectively, and the ports mapping of the Nginx service is mapped to ports 80 and 443 of the host machine, which can lead to conflicts with the host machine's already running Nginx.

If you want to set up a direct Nginx reverse proxy along with other services running on the host machine, changing the EXPOSE ports to arbitrary values that are not in use will solve the issue, but the unused Nginx Docker container will still be running.

Proposal

Introduce an option: NGINX_ENABLED: ${NGINX_ENABLED:-false}
and provide a choice to not use Nginx.

I believe this change will give more flexibility to the deployment environment using Docker.

2. Additional context or comments

No response

3. Can you help us with this feature?

• I am interested in contributing to this feature.