Fix Dockerfile and Compose deprecation warnings

Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.23.3 as build
+FROM alpine:3.23.3 AS build
 
 ARG SQUID_VER=7.4
 
@@ -105,8 +105,8 @@ RUN sed -i '1s;^;include /etc/squid/conf.d/*.conf\n;' /etc/squid/squid.conf && \
 
 FROM alpine:3.23.3
 	
-ENV SQUID_CONFIG_FILE /etc/squid/squid.conf
-ENV TZ Europe/Moscow
+ENV SQUID_CONFIG_FILE=/etc/squid/squid.conf
+ENV TZ=Europe/Moscow
 
 RUN set -x && \
 	deluser squid 2>/dev/null; delgroup squid 2>/dev/null; \

README.md

@@ -38,6 +38,13 @@ The image also includes `apache2-utils`, so you can generate and manage `htpassw
 ## Environment variables:
 
 - **SQUID_CONFIG_FILE**: Specify the configuration file for squid. Defaults to `/etc/squid/squid.conf`.
+- **TZ**: Override the container timezone (for example, `Europe/Berlin`).
+
+You can configure Squid in multiple ways:
+
+- Replace the main configuration file by overriding `SQUID_CONFIG_FILE`.
+- Add configuration snippets to `/etc/squid/conf.d`: all `*.conf` files from this directory are included at the **beginning** of the default configuration.
+- Add configuration snippets to `/etc/squid/conf.d.tail`: all `*.conf` files from this directory are included at the **end** of the default configuration.
 
 ## Example:
 

docker-compose.test.yml

@@ -1,4 +1,3 @@
-version: '2.3'
 services:
   proxy:
     image: "${TEST_TAG}"

docker-compose.yml

@@ -1,4 +1,3 @@
-version: '2'
 services:
   squid:
     image: 'b4tman/squid'