add 15-to-16 support

15-to-16/Dockerfile

@@ -0,0 +1,25 @@
+FROM postgres:16-bookworm
+
+RUN sed -i 's/$/ 15/' /etc/apt/sources.list.d/pgdg.list
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+		postgresql-15 \
+	&& rm -rf /var/lib/apt/lists/*
+
+ENV PGBINOLD /usr/lib/postgresql/15/bin
+ENV PGBINNEW /usr/lib/postgresql/16/bin
+
+ENV PGDATAOLD /var/lib/postgresql/15/data
+ENV PGDATANEW /var/lib/postgresql/16/data
+
+RUN mkdir -p "$PGDATAOLD" "$PGDATANEW" \
+	&& chown -R postgres:postgres /var/lib/postgresql
+
+WORKDIR /var/lib/postgresql
+
+COPY docker-upgrade /usr/local/bin/
+
+ENTRYPOINT ["docker-upgrade"]
+
+# recommended: --link
+CMD ["pg_upgrade"]

15-to-16/docker-upgrade

@@ -0,0 +1,22 @@
+#!/bin/bash
+set -e
+
+if [ "$#" -eq 0 -o "${1:0:1}" = '-' ]; then
+	set -- pg_upgrade "$@"
+fi
+
+if [ "$1" = 'pg_upgrade' -a "$(id -u)" = '0' ]; then
+	mkdir -p "$PGDATAOLD" "$PGDATANEW"
+	chmod 700 "$PGDATAOLD" "$PGDATANEW"
+	chown postgres .
+	chown -R postgres "$PGDATAOLD" "$PGDATANEW"
+	exec gosu postgres "$BASH_SOURCE" "$@"
+fi
+
+if [ "$1" = 'pg_upgrade' ]; then
+	if [ ! -s "$PGDATANEW/PG_VERSION" ]; then
+		PGDATA="$PGDATANEW" eval "initdb $POSTGRES_INITDB_ARGS"
+	fi
+fi
+
+exec "$@"

update.sh

@@ -3,6 +3,7 @@ set -Eeuo pipefail
 
 # TODO scrape this somehow?
 supportedVersions=(
+	16
 	15
 	14
 	13