Here's my very minimal setup, which makes Laravel workable in Docker. Previously, it doesn't work, because it didn't include the following line in Nginx container. (Although error happens in Laravel container)

root /var/www/html/public;

laravel/Dockerfile

FROM php:7.2.8-fpm-alpine3.7

# Install tools to download Laravel framework. 
RUN apk update && \
    apk add git && \
    apk add unzip
	
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer	
	
# Download Laravel framework in correct directory.
RUN composer create-project --prefer-dist laravel/laravel /var/www/html/

# Copy and overwrite with files from host (including hidden file) to Laravel directory.
COPY . /tmp/files-from-host
RUN true | cp -ai /tmp/files-from-host/. /var/www/html/ 2>/dev/null
RUN rm -rf /tmp/files-from-host/

WORKDIR /var/www/html

# Avoid error "The stream or file "/var/www/html/storage/logs/laravel.log" could not be opened: failed to open stream: Permission denied"
RUN chown -R www-data:www-data /var/www/html/storage

CMD ["php-fpm", "-F"]

nginx/default.conf

server {
    listen 443;
    ssl on;
    root /var/www/html/public;

    ssl_certificate /app/cert.pem;
    ssl_certificate_key /app/key.pem;
    
    location / {
        try_files $uri /index.php?$args;
    }

    location ~ \.php$ {
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        fastcgi_pass laravel:9000;
        fastcgi_index index.php;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_param PATH_INFO $fastcgi_path_info;
	}	
}

nginx/Dockerfile

FROM nginx:1.13.9-alpine

COPY . /app

RUN rm /etc/nginx/conf.d/default.conf
COPY default.conf /etc/nginx/conf.d/

docker-compose.yml

version: '2'
services:

  # Note, SSL cert (cert.pem and key.pem) is generated from cloudflare.
  nginx:
    build:
      context: ./nginx
      dockerfile: Dockerfile
    restart: always
    ports:
     - "2053:443"

     
  laravel:
    build:
      context: ./laravel
      dockerfile: Dockerfile
    restart: always

You can then access Laravel app using

https://localhost:2053/