setup: Rename postgresql-init-db to create-database.

The old name was confusingly similar to initialize-database.

scripts/setup/create-database

@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+set -e
+
+if [ "$EUID" -ne 0 ]; then
+    echo "Error: This script must be run as root" >&2
+    exit 1
+fi
+set -x
+
+# What user should we use for connecting to the database
+POSTGRES_USER="${POSTGRES_USER:-postgres}"
+
+# What database name and username to use when connecting to the database
+DATABASE_NAME=$(crudini --get /etc/zulip/zulip.conf postgresql database_name 2>/dev/null || echo zulip)
+DATABASE_USER=$(crudini --get /etc/zulip/zulip.conf postgresql database_user 2>/dev/null || echo zulip)
+
+# This psql command may fail because the Zulip database doesn’t exist,
+# hence the &&.
+if records="$(
+    cd / # Make sure the current working directory is readable by postgres
+    su "$POSTGRES_USER" -c "psql -v ON_ERROR_STOP=1 -Atc 'SELECT COUNT(*) FROM $DATABASE_NAME.zerver_message;' $DATABASE_USER"
+)" && [ "$records" -gt 200 ]; then
+    set +x
+    echo "WARNING: This will delete your Zulip database which currently contains $records messages."
+    read -p "Do you want to proceed? [y/N] " -r
+    echo
+    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+        exit 1
+    fi
+    set -x
+fi
+
+# Shut down all services to ensure a quiescent state.
+if [ -e "/var/run/supervisor.sock" ]; then
+    supervisorctl stop all
+fi
+
+# Drop any open connections to any old database.
+# Send the script via stdin in case the postgres user lacks permission to read it.
+su -s /usr/bin/env - -- "$POSTGRES_USER" \
+    bash -s - zulip zulip_base <"$(dirname "$0")/terminate-psql-sessions"
+
+(
+    cd / # Make sure the current working directory is readable by postgres
+    su "$POSTGRES_USER" -c "psql -v ON_ERROR_STOP=1 -v dbname=$DATABASE_NAME -v dbuser=$DATABASE_USER -e"
+) <"$(dirname "$0")/create-db.sql"
+
+# Set a postgres password if the postgres username is not "zulip".
+# When the username is zulip, we rely on running as the zulip system
+# user for authentication via postgres' peer authentication.
+if [ "$DATABASE_USER" != "zulip" ]; then
+    PASSWORD=$(crudini --get /etc/zulip/zulip-secrets.conf secrets postgres_password)
+    su "$POSTGRES_USER" -c "psql -v ON_ERROR_STOP=1  -e postgres" <<EOF
+ALTER ROLE $DATABASE_USER PASSWORD '$PASSWORD';
+EOF
+fi
+
+# Clear memcached to avoid contamination from previous database state
+"$(dirname "$0")/flush-memcached"
+
+echo "Database created"