From 31f4a547a9d4e8a7450589877c163203462b9905 Mon Sep 17 00:00:00 2001
From: Sebastian Kippe <sebastian@kip.pe>
Date: Thu, 23 Dec 2021 13:06:32 +0100
Subject: [PATCH] Backup LND SCB to S3 on change

closes #359
---
 nodes/bitcoin-2.json                          |  9 ++--
 .../kosmos-bitcoin/recipes/lnd-scb-s3.rb      | 47 +++++++++++++++++++
 .../templates/lnd-channel-backup-s3.sh.erb    |  7 +++
 3 files changed, 60 insertions(+), 3 deletions(-)
 create mode 100644 site-cookbooks/kosmos-bitcoin/recipes/lnd-scb-s3.rb
 create mode 100644 site-cookbooks/kosmos-bitcoin/templates/lnd-channel-backup-s3.sh.erb

diff --git a/nodes/bitcoin-2.json b/nodes/bitcoin-2.json
index aaa9fcf..5340527 100644
--- a/nodes/bitcoin-2.json
+++ b/nodes/bitcoin-2.json
@@ -23,6 +23,7 @@
       "kosmos-bitcoin::source",
       "kosmos-bitcoin::c-lightning",
       "kosmos-bitcoin::lnd",
+      "kosmos-bitcoin::lnd-scb-s3",
       "kosmos-bitcoin::rtl",
       "kosmos-bitcoin::lndhub",
       "kosmos_postgresql::hostsfile",
@@ -48,6 +49,9 @@
       "git::default",
       "git::package",
       "golang::default",
+      "backup::default",
+      "logrotate::default",
+      "kosmos-bitcoin::aws-client",
       "kosmos-nodejs::default",
       "nodejs::nodejs_from_package",
       "nodejs::repo",
@@ -70,9 +74,7 @@
       "nginx::commons_dir",
       "nginx::commons_script",
       "nginx::commons_conf",
-      "kosmos-nginx::firewall",
-      "backup::default",
-      "logrotate::default"
+      "kosmos-nginx::firewall"
     ],
     "platform": "ubuntu",
     "platform_version": "20.04",
@@ -94,6 +96,7 @@
     "recipe[kosmos-bitcoin::source]",
     "recipe[kosmos-bitcoin::c-lightning]",
     "recipe[kosmos-bitcoin::lnd]",
+    "recipe[kosmos-bitcoin::lnd-scb-s3]",
     "recipe[kosmos-bitcoin::rtl]",
     "recipe[kosmos-bitcoin::lndhub]",
     "role[btcpay]"
diff --git a/site-cookbooks/kosmos-bitcoin/recipes/lnd-scb-s3.rb b/site-cookbooks/kosmos-bitcoin/recipes/lnd-scb-s3.rb
new file mode 100644
index 0000000..25d794d
--- /dev/null
+++ b/site-cookbooks/kosmos-bitcoin/recipes/lnd-scb-s3.rb
@@ -0,0 +1,47 @@
+#
+# Cookbook:: kosmos-bitcoin
+# Recipe:: lnd-scb-s3
+#
+# Static Channel Backup for LND channel states
+#
+
+include_recipe "kosmos-bitcoin::aws-client"
+
+package "inotify-tools"
+
+backup_script_path = "/opt/lnd-channel-backup-s3.sh"
+
+template backup_script_path do
+  source "lnd-channel-backup-s3.sh.erb"
+  mode '0740'
+  variables lnd_dir: node['lnd']['lnd_dir'],
+            bitcoin_network: node['bitcoin']['network'],
+            s3_bucket: node['backup']['s3']['bucket'],
+            s3_scb_dir: "#{node['name']}/lnd/#{node['bitcoin']['network']}"
+  notifies :restart, "systemd_unit[lnd-channel-backup.service]", :delayed
+end
+
+systemd_unit 'lnd-channel-backup.service' do
+  content({
+    Unit: {
+      Description: 'LND Static Channel Backup',
+      Documentation: ['https://gist.github.com/alexbosworth/2c5e185aedbdac45a03655b709e255a3'],
+      Requires: 'lnd.service',
+      After: 'lnd.service'
+    },
+    Service: {
+      User: 'root',
+      Group: 'root',
+      Type: 'simple',
+      ExecStart: backup_script_path,
+      Restart: 'always',
+      RestartSec: 1
+    },
+    Install: {
+      WantedBy: 'multi-user.target'
+    }
+  })
+  verify false
+  triggers_reload true
+  action [:create, :enable, :start]
+end
diff --git a/site-cookbooks/kosmos-bitcoin/templates/lnd-channel-backup-s3.sh.erb b/site-cookbooks/kosmos-bitcoin/templates/lnd-channel-backup-s3.sh.erb
new file mode 100644
index 0000000..d5b1c80
--- /dev/null
+++ b/site-cookbooks/kosmos-bitcoin/templates/lnd-channel-backup-s3.sh.erb
@@ -0,0 +1,7 @@
+#!/bin/bash
+set -xe -o pipefail
+
+while true; do
+  inotifywait <%= @lnd_dir %>/data/chain/bitcoin/<%= @bitcoin_network %>/channel.backup
+  aws s3 cp <%= @lnd_dir %>/data/chain/bitcoin/<%= @bitcoin_network %>/channel.backup "s3://<%= @s3_bucket %>/<%= @s3_scb_dir %>/channel.backup"
+done