added gce_ssh_keyscan.sh

Author: HariSekhon

gcp/gce_ssh_keyscan.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+#  vim:ts=4:sts=4:sw=4:et
+#
+#  Author: Hari Sekhon
+#  Date: 2024-02-28 12:40:41 +0000 (Wed, 28 Feb 2024)
+#
+#  https///github.com/HariSekhon/DevOps-Bash-tools
+#
+#  License: see accompanying Hari Sekhon LICENSE file
+#
+#  If you're using my code you're welcome to connect with me on LinkedIn and optionally send me feedback to help steer this or other code I publish
+#
+#  https://www.linkedin.com/in/HariSekhon
+#
+
+set -euo pipefail
+[ -n "${DEBUG:-}" ] && set -x
+srcdir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# shellcheck disable=SC1090,SC1091
+. "$srcdir/lib/utils.sh"
+
+# shellcheck disable=SC2034,SC2154
+usage_description="
+SSH keyscans all the GCE VM hosts that match the given regex filter to add them to SSH known_hosts
+
+Useful to doing direct SSH to hosts and especially for Ansible to speed up not going through IAP which is slow
+and not having them prompt to accept the SSH keys
+"
+
+# used by usage() in lib/utils.sh
+# shellcheck disable=SC2034
+usage_args="[<regex_filter> <gcloud_cli_options>]"
+
+help_usage "$@"
+
+#max_args 1 "$@"
+
+ssh_known_hosts_file=~/.ssh/known_hosts
+
+"$srcdir/gce_host_ips.sh" "$@" |
+while read -r ip hostname; do
+    ssh-keyscan "$ip" >> "$ssh_known_hosts_file"
+    ssh-keyscan "$hostname" >> "$ssh_known_hosts_file"
+done