Add dockerfile for local development

Dockerfile

@@ -0,0 +1,6 @@
+# this is a development container, not hardened for hosting
+FROM php:7.4-cli
+RUN apt-get update && \
+	apt-get install -y \
+		sqlite \
+		unzip

README.md

@@ -23,7 +23,7 @@ On Windows, you have to perform a `composer install` manually beforehand. Make s
 ### Dependency management
 
 `dev.sh` will ensure the git submodules have been pulled, then download the `composer` package manager to the php archive file `composer.phar` and run it.
-Composer will check for the php extension `pdo_sqlite` which must be enabled on your system. This usually includes installing a php-sqlite3 package and enabling it in /etc/php/php.ini:
+Composer will check for the php extension `pdo_sqlite` which must be enabled on your system. This usually includes installing a php-sqlite3 package and enabling it in `/etc/php/php.ini`:
 
     [PHP]
     extension=pdo_sqlite
@@ -35,4 +35,16 @@ Composer is used as such:
     php composer.phar update
     php composer.phar install
 
+### Docker
+
+We provide a simple docker-compose setup for local development.
+First ensure that docker is running:
+
+	sudo systemctl start docker
+
+then
+
+	DOCKER_USER=$(id -u):$(id -g) docker-compose up
+
+
 ## Hosting

dev.sh

@@ -22,4 +22,4 @@ if test ! -d vendor; then
 	ln -s ../vendor/simplesamlphp/simplesamlphp/www/ www/simplesaml
 fi
 
-php -S [::1]:1080 -d error_reporting=E_ALL -d display_errors=1 -t www/
+php -S ${DOCKER_HOST:-[::1]}:${DOCKER_PORT:-1080} -d error_reporting=E_ALL -d display_errors=1 -t www/

docker-compose.yaml

@@ -0,0 +1,21 @@
+version: "3.9"
+
+# cleanup:
+
+# docker container prune -f && docker volume prune -f
+# docker system prune -a
+
+services:
+  nettside: # https://hub.docker.com/_/php
+    #image: php:7.4-cli
+    build: .
+    volumes:
+      - .:/usr/src/nettside
+    working_dir: /usr/src/nettside
+    command: ./dev.sh
+    environment:
+      - DOCKER_HOST=0.0.0.0
+      - DOCKER_PORT=1080
+    ports:
+      - 1080:1080
+    user: "${DOCKER_USER}"