From a2187a6ce9d4fde147a45f195557944393369ad5 Mon Sep 17 00:00:00 2001 From: Federico Justus Denkena Date: Fri, 3 May 2024 03:43:28 +0200 Subject: [PATCH] add missing files --- docker-ensure-initdb.sh | 71 ++++++++ docker-entrypoint.sh | 356 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 427 insertions(+) create mode 100644 docker-ensure-initdb.sh create mode 100644 docker-entrypoint.sh diff --git a/docker-ensure-initdb.sh b/docker-ensure-initdb.sh new file mode 100644 index 0000000..ae1f6b6 --- /dev/null +++ b/docker-ensure-initdb.sh @@ -0,0 +1,71 @@ +#!/usr/bin/env bash +set -Eeuo pipefail + +# +# This script is intended for three main use cases: +# +# 1. (most importantly) as an example of how to use "docker-entrypoint.sh" to extend/reuse the initialization behavior +# +# 2. ("docker-ensure-initdb.sh") as a Kubernetes "init container" to ensure the provided database directory is initialized; see also "startup probes" for an alternative solution +# (no-op if database is already initialized) +# +# 3. ("docker-enforce-initdb.sh") as part of CI to ensure the database is fully initialized before use +# (error if database is already initialized) +# + +source /usr/local/bin/docker-entrypoint.sh + +# arguments to this script are assumed to be arguments to the "postgres" server (same as "docker-entrypoint.sh"), and most "docker-entrypoint.sh" functions assume "postgres" is the first argument (see "_main" over there) +if [ "$#" -eq 0 ] || [ "$1" != 'postgres' ]; then + set -- postgres "$@" +fi + +# see also "_main" in "docker-entrypoint.sh" + +docker_setup_env +# setup data directories and permissions (when run as root) +docker_create_db_directories +if [ "$(id -u)" = '0' ]; then + # then restart script as postgres user + exec gosu postgres "$BASH_SOURCE" "$@" +fi + +# only run initialization on an empty data directory +if [ -z "$DATABASE_ALREADY_EXISTS" ]; then + docker_verify_minimum_env + + # check dir permissions to reduce likelihood of half-initialized database + ls /docker-entrypoint-initdb.d/ > /dev/null + + docker_init_database_dir + pg_setup_hba_conf "$@" + + # PGPASSWORD is required for psql when authentication is required for 'local' connections via pg_hba.conf and is otherwise harmless + # e.g. when '--auth=md5' or '--auth-local=md5' is used in POSTGRES_INITDB_ARGS + export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}" + docker_temp_server_start "$@" + + docker_setup_db + docker_process_init_files /docker-entrypoint-initdb.d/* + + docker_temp_server_stop + unset PGPASSWORD +else + self="$(basename "$0")" + case "$self" in + docker-ensure-initdb.sh) + echo >&2 "$self: note: database already initialized in '$PGDATA'!" + exit 0 + ;; + + docker-enforce-initdb.sh) + echo >&2 "$self: error: (unexpected) database found in '$PGDATA'!" + exit 1 + ;; + + *) + echo >&2 "$self: error: unknown file name: $self" + exit 99 + ;; + esac +fi diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh new file mode 100644 index 0000000..6f59993 --- /dev/null +++ b/docker-entrypoint.sh @@ -0,0 +1,356 @@ +#!/usr/bin/env bash +set -Eeo pipefail +# TODO swap to -Eeuo pipefail above (after handling all potentially-unset variables) + +# usage: file_env VAR [DEFAULT] +# ie: file_env 'XYZ_DB_PASSWORD' 'example' +# (will allow for "$XYZ_DB_PASSWORD_FILE" to fill in the value of +# "$XYZ_DB_PASSWORD" from a file, especially for Docker's secrets feature) +file_env() { + local var="$1" + local fileVar="${var}_FILE" + local def="${2:-}" + if [ "${!var:-}" ] && [ "${!fileVar:-}" ]; then + printf >&2 'error: both %s and %s are set (but are exclusive)\n' "$var" "$fileVar" + exit 1 + fi + local val="$def" + if [ "${!var:-}" ]; then + val="${!var}" + elif [ "${!fileVar:-}" ]; then + val="$(< "${!fileVar}")" + fi + export "$var"="$val" + unset "$fileVar" +} + +# check to see if this file is being run or sourced from another script +_is_sourced() { + # https://unix.stackexchange.com/a/215279 + [ "${#FUNCNAME[@]}" -ge 2 ] \ + && [ "${FUNCNAME[0]}" = '_is_sourced' ] \ + && [ "${FUNCNAME[1]}" = 'source' ] +} + +# used to create initial postgres directories and if run as root, ensure ownership to the "postgres" user +docker_create_db_directories() { + local user; user="$(id -u)" + + mkdir -p "$PGDATA" + # ignore failure since there are cases where we can't chmod (and PostgreSQL might fail later anyhow - it's picky about permissions of this directory) + chmod 00700 "$PGDATA" || : + + # ignore failure since it will be fine when using the image provided directory; see also https://github.com/docker-library/postgres/pull/289 + mkdir -p /var/run/postgresql || : + chmod 03775 /var/run/postgresql || : + + # Create the transaction log directory before initdb is run so the directory is owned by the correct user + if [ -n "${POSTGRES_INITDB_WALDIR:-}" ]; then + mkdir -p "$POSTGRES_INITDB_WALDIR" + if [ "$user" = '0' ]; then + find "$POSTGRES_INITDB_WALDIR" \! -user postgres -exec chown postgres '{}' + + fi + chmod 700 "$POSTGRES_INITDB_WALDIR" + fi + + # allow the container to be started with `--user` + if [ "$user" = '0' ]; then + find "$PGDATA" \! -user postgres -exec chown postgres '{}' + + find /var/run/postgresql \! -user postgres -exec chown postgres '{}' + + fi +} + +# initialize empty PGDATA directory with new database via 'initdb' +# arguments to `initdb` can be passed via POSTGRES_INITDB_ARGS or as arguments to this function +# `initdb` automatically creates the "postgres", "template0", and "template1" dbnames +# this is also where the database user is created, specified by `POSTGRES_USER` env +docker_init_database_dir() { + # "initdb" is particular about the current user existing in "/etc/passwd", so we use "nss_wrapper" to fake that if necessary + # see https://github.com/docker-library/postgres/pull/253, https://github.com/docker-library/postgres/issues/359, https://cwrap.org/nss_wrapper.html + local uid; uid="$(id -u)" + if ! getent passwd "$uid" &> /dev/null; then + # see if we can find a suitable "libnss_wrapper.so" (https://salsa.debian.org/sssd-team/nss-wrapper/-/commit/b9925a653a54e24d09d9b498a2d913729f7abb15) + local wrapper + for wrapper in {/usr,}/lib{/*,}/libnss_wrapper.so; do + if [ -s "$wrapper" ]; then + NSS_WRAPPER_PASSWD="$(mktemp)" + NSS_WRAPPER_GROUP="$(mktemp)" + export LD_PRELOAD="$wrapper" NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP + local gid; gid="$(id -g)" + printf 'postgres:x:%s:%s:PostgreSQL:%s:/bin/false\n' "$uid" "$gid" "$PGDATA" > "$NSS_WRAPPER_PASSWD" + printf 'postgres:x:%s:\n' "$gid" > "$NSS_WRAPPER_GROUP" + break + fi + done + fi + + if [ -n "${POSTGRES_INITDB_WALDIR:-}" ]; then + set -- --waldir "$POSTGRES_INITDB_WALDIR" "$@" + fi + + # --pwfile refuses to handle a properly-empty file (hence the "\n"): https://github.com/docker-library/postgres/issues/1025 + eval 'initdb --username="$POSTGRES_USER" --pwfile=<(printf "%s\n" "$POSTGRES_PASSWORD") '"$POSTGRES_INITDB_ARGS"' "$@"' + + # unset/cleanup "nss_wrapper" bits + if [[ "${LD_PRELOAD:-}" == */libnss_wrapper.so ]]; then + rm -f "$NSS_WRAPPER_PASSWD" "$NSS_WRAPPER_GROUP" + unset LD_PRELOAD NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP + fi +} + +# print large warning if POSTGRES_PASSWORD is long +# error if both POSTGRES_PASSWORD is empty and POSTGRES_HOST_AUTH_METHOD is not 'trust' +# print large warning if POSTGRES_HOST_AUTH_METHOD is set to 'trust' +# assumes database is not set up, ie: [ -z "$DATABASE_ALREADY_EXISTS" ] +docker_verify_minimum_env() { + case "${PG_MAJOR:-}" in + 12 | 13) # https://github.com/postgres/postgres/commit/67a472d71c98c3d2fa322a1b4013080b20720b98 + # check password first so we can output the warning before postgres + # messes it up + if [ "${#POSTGRES_PASSWORD}" -ge 100 ]; then + cat >&2 <<-'EOWARN' + + WARNING: The supplied POSTGRES_PASSWORD is 100+ characters. + + This will not work if used via PGPASSWORD with "psql". + + https://www.postgresql.org/message-id/flat/E1Rqxp2-0004Qt-PL%40wrigleys.postgresql.org (BUG #6412) + https://github.com/docker-library/postgres/issues/507 + + EOWARN + fi + ;; + esac + if [ -z "$POSTGRES_PASSWORD" ] && [ 'trust' != "$POSTGRES_HOST_AUTH_METHOD" ]; then + # The - option suppresses leading tabs but *not* spaces. :) + cat >&2 <<-'EOE' + Error: Database is uninitialized and superuser password is not specified. + You must specify POSTGRES_PASSWORD to a non-empty value for the + superuser. For example, "-e POSTGRES_PASSWORD=password" on "docker run". + + You may also use "POSTGRES_HOST_AUTH_METHOD=trust" to allow all + connections without a password. This is *not* recommended. + + See PostgreSQL documentation about "trust": + https://www.postgresql.org/docs/current/auth-trust.html + EOE + exit 1 + fi + if [ 'trust' = "$POSTGRES_HOST_AUTH_METHOD" ]; then + cat >&2 <<-'EOWARN' + ******************************************************************************** + WARNING: POSTGRES_HOST_AUTH_METHOD has been set to "trust". This will allow + anyone with access to the Postgres port to access your database without + a password, even if POSTGRES_PASSWORD is set. See PostgreSQL + documentation about "trust": + https://www.postgresql.org/docs/current/auth-trust.html + In Docker's default configuration, this is effectively any other + container on the same system. + + It is not recommended to use POSTGRES_HOST_AUTH_METHOD=trust. Replace + it with "-e POSTGRES_PASSWORD=password" instead to set a password in + "docker run". + ******************************************************************************** + EOWARN + fi +} + +# usage: docker_process_init_files [file [file [...]]] +# ie: docker_process_init_files /always-initdb.d/* +# process initializer files, based on file extensions and permissions +docker_process_init_files() { + # psql here for backwards compatibility "${psql[@]}" + psql=( docker_process_sql ) + + printf '\n' + local f + for f; do + case "$f" in + *.sh) + # https://github.com/docker-library/postgres/issues/450#issuecomment-393167936 + # https://github.com/docker-library/postgres/pull/452 + if [ -x "$f" ]; then + printf '%s: running %s\n' "$0" "$f" + "$f" + else + printf '%s: sourcing %s\n' "$0" "$f" + . "$f" + fi + ;; + *.sql) printf '%s: running %s\n' "$0" "$f"; docker_process_sql -f "$f"; printf '\n' ;; + *.sql.gz) printf '%s: running %s\n' "$0" "$f"; gunzip -c "$f" | docker_process_sql; printf '\n' ;; + *.sql.xz) printf '%s: running %s\n' "$0" "$f"; xzcat "$f" | docker_process_sql; printf '\n' ;; + *.sql.zst) printf '%s: running %s\n' "$0" "$f"; zstd -dc "$f" | docker_process_sql; printf '\n' ;; + *) printf '%s: ignoring %s\n' "$0" "$f" ;; + esac + printf '\n' + done +} + +# Execute sql script, passed via stdin (or -f flag of pqsl) +# usage: docker_process_sql [psql-cli-args] +# ie: docker_process_sql --dbname=mydb <<<'INSERT ...' +# ie: docker_process_sql -f my-file.sql +# ie: docker_process_sql > "$PGDATA/pg_hba.conf" +} + +# start socket-only postgresql server for setting up or running scripts +# all arguments will be passed along as arguments to `postgres` (via pg_ctl) +docker_temp_server_start() { + if [ "$1" = 'postgres' ]; then + shift + fi + + # internal start of server in order to allow setup using psql client + # does not listen on external TCP/IP and waits until start finishes + set -- "$@" -c listen_addresses='' -p "${PGPORT:-5432}" + + PGUSER="${PGUSER:-$POSTGRES_USER}" \ + pg_ctl -D "$PGDATA" \ + -o "$(printf '%q ' "$@")" \ + -w start +} + +# stop postgresql server after done setting up user and running scripts +docker_temp_server_stop() { + PGUSER="${PGUSER:-postgres}" \ + pg_ctl -D "$PGDATA" -m fast -w stop +} + +# check arguments for an option that would cause postgres to stop +# return true if there is one +_pg_want_help() { + local arg + for arg; do + case "$arg" in + # postgres --help | grep 'then exit' + # leaving out -C on purpose since it always fails and is unhelpful: + # postgres: could not access the server configuration file "/var/lib/postgresql/data/postgresql.conf": No such file or directory + -'?'|--help|--describe-config|-V|--version) + return 0 + ;; + esac + done + return 1 +} + +_main() { + # if first arg looks like a flag, assume we want to run postgres server + if [ "${1:0:1}" = '-' ]; then + set -- postgres "$@" + fi + + if [ "$1" = 'postgres' ] && ! _pg_want_help "$@"; then + docker_setup_env + # setup data directories and permissions (when run as root) + docker_create_db_directories + if [ "$(id -u)" = '0' ]; then + # then restart script as postgres user + exec gosu postgres "$BASH_SOURCE" "$@" + fi + + # only run initialization on an empty data directory + if [ -z "$DATABASE_ALREADY_EXISTS" ]; then + docker_verify_minimum_env + + # check dir permissions to reduce likelihood of half-initialized database + ls /docker-entrypoint-initdb.d/ > /dev/null + + docker_init_database_dir + pg_setup_hba_conf "$@" + + # PGPASSWORD is required for psql when authentication is required for 'local' connections via pg_hba.conf and is otherwise harmless + # e.g. when '--auth=md5' or '--auth-local=md5' is used in POSTGRES_INITDB_ARGS + export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}" + docker_temp_server_start "$@" + + docker_setup_db + docker_process_init_files /docker-entrypoint-initdb.d/* + + docker_temp_server_stop + unset PGPASSWORD + + cat <<-'EOM' + + PostgreSQL init process complete; ready for start up. + + EOM + else + cat <<-'EOM' + + PostgreSQL Database directory appears to contain a database; Skipping initialization + + EOM + fi + fi + + exec "$@" +} + +if ! _is_sourced; then + _main "$@" +fi