Let users install a smaller but English-only ICU lib (#612)

README.md

@@ -371,6 +371,7 @@ Here's the list of all the supported environment variables:
 | event | `IPE_EVENT_NAMESPACE=`... | By default the `event` classes are defined in the root namespace. You can use this environment variable to specify a custom namespace |
 | gd | `IPE_GD_WITHOUTAVIF=1` | Since PHP 8.1, gd supports the AVIF format. Enabling it requires compiling libaom/libdav1d/libyuv/libavif, which is time-consuming. You can disable AVIF support by setting this environment variable |
 | oci8 & pdo_oci | `IPE_INSTANTCLIENT_BASIC=1` | The oci8 and pdo_oci PHP extensions require [Oracle Instant Client](https://www.oracle.com/database/technologies/instant-client.html). In order to save disk space, we install the Basic Lite version: if you want to install the Basic (non-lite) version simply set this environment variable |
+| http, intl, mongodb | `IPE_ICU_EN_ONLY=1` | Some extensions require the ICU library, use this flag to install a smaller, but English-only, ICU library on Alpine 3.16 and later |
 
 ## Special requirements
 

install-php-extensions

@@ -610,7 +610,12 @@ buildRequiredPackageLists() {
 			fi
 			buildRequiredPackageLists_icuPersistent=''
 			if test $DISTRO_MAJMIN_VERSION -ge 316; then
-				buildRequiredPackageLists_icuPersistent='icu-data-full'
+				case "${IPE_ICU_EN_ONLY:-}" in
+					1 | y* | Y*) ;;
+					*)
+						buildRequiredPackageLists_icuPersistent='icu-data-full'
+						;;
+				esac
 			fi
 			;;
 		debian@9)