chore(cookies): update great-names challenge

Signed-off-by: Gabriel Mocanu <gabi.mocanu98@gmail.com>

Author: gabrielmocanu

chapters/web-application-security/cookies-and-session-management/drills/great-names/deploy/Dockerfile

@@ -1,3 +1,11 @@
+# Stage 1: Generate the source file with the flag
+FROM alpine:latest AS builder
+
+ARG FLAG
+COPY src/index.template.php /tmp/index.template.php
+RUN sed "s/__TEMPLATE__/${FLAG}/g" /tmp/index.template.php > /tmp/index.php
+
+# Stage 2: Final image
 FROM php:7.2-apache
 
-COPY /public /var/www/html/
+COPY --from=builder /tmp/index.php /var/www/html/

chapters/web-application-security/cookies-and-session-management/drills/great-names/deploy/Makefile

@@ -1,16 +1,19 @@
-FILE	:=../flag
-FLAG	:=$(shell cat $(FILE))
-
-build:
-	docker build -f Dockerfile -t sss-web-02_great-names ..
+EXTERNAL_PORT := 8080
+INTERNAL_PORT := 80
+NAME := cookies-and-session-management_great-names
+FLAG := $(shell cat ../flag)
 
 run: build
-	docker run -d -p 8080:80 --name sss-web-02_great-names sss-web-02_great-names
+	docker run -d -p $(EXTERNAL_PORT):$(INTERNAL_PORT) --name $(NAME) -t $(NAME)
+
+build:
+	docker build --build-arg FLAG="$(FLAG)" -t $(NAME) -f Dockerfile ..
 
 stop:
-	docker stop sss-web-02_great-names
+	docker stop $(NAME)
 
 clean: stop
-	docker rm sss-web-02_great-names
+	docker rm $(NAME)
+	docker image rm $(NAME):latest
 
-.PHONY: build run stop clean
+.PHONY: run build stop clean