From 281068a7529fd4f008d3acb50ad843bf37c23226 Mon Sep 17 00:00:00 2001
From: tomg10 <lemures64@gmail.com>
Date: Thu, 21 Mar 2024 16:01:41 +0100
Subject: [PATCH] support for snapshots recovery

---
 README.md                      | 11 ++++++++++-
 defaults/main.yml              |  4 ++++
 templates/external_node.env.j2 |  6 ++++++
 templates/restore_dump.sh.j2   |  2 +-
 4 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 1e09f9c..4dc73fe 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,7 @@ Basic auth secret can be generated by `htpasswd` and `sed` for interpolation:
 `ansible-galaxy collection install community.general`
 
 2. Prepare the latest database backup on your host. you can download it from our public GCS buckets:
+Skip this step if you are recovering from a snapshot!
 
 * [Era Mainnet latest dump](https://storage.googleapis.com/zksync-era-mainnet-external-node-backups/external_node_latest.pgdump)
 * [Era Sepolia Testnet latest dump](https://storage.googleapis.com/zksync-era-boojnet-external-node-snapshots/external_node_latest.pgdump)
@@ -95,6 +96,7 @@ Basic auth secret can be generated by `htpasswd` and `sed` for interpolation:
 Downloaded dump file should be placed into `{{ storage_directory }}/pg_backups` directory (`/usr/src/en/pg_backups` by default)
 
 3. **OPTIONAL**: If you already have running node, you can copy its tree and state directory to a new host's `{{ storage_directory }}/db`. (`/usr/src/en/db` by default)
+Skip this step if you are recovering from a snapshot!
 
 **Keep in mind that tree and state should be older than PostgreSQL database backup.**
 
@@ -110,6 +112,14 @@ vm_auth_password
 
 5. Connect to your host, and see status of `postgres` container. It can take a lot of time before PostgreSQL database backup will be restored (hours to days, depending on your disk throughput and IOPS), after which PostgreSQL server will be ready for use. Once `postgres` becomes "healthy", `external_node` runs automatically.
 
+## Snapshots Recovery
+
+example config enabling recovery from a snapshot
+```yaml
+- enable_snapshots_recovery: true
+- snapshots_bucket_base_url: "zksync-era-mainnet-external-node-snapshots"
+```
+
 ## Example Playbook
 
 ```yaml
@@ -125,7 +135,6 @@ vm_auth_password
     l2_chain_id: "324"
     l1_chain_id: "1"
     enable_tls: false
-    partner_id: matterlabs
   vars_files:
     - secrets/mainnet_secrets.yml
   roles:
diff --git a/defaults/main.yml b/defaults/main.yml
index 464f8a9..58aa4bc 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -68,6 +68,10 @@ basic_auth_secret: ""
 # Force restore pg database
 force_pg_restore: false
 
+# Use a snapshot to recover
+enable_snapshots_recovery: false
+snapshots_bucket_base_url: ""
+
 # External node and database options
 database_name: ""
 database_username: ""
diff --git a/templates/external_node.env.j2 b/templates/external_node.env.j2
index 3931794..20c5a50 100644
--- a/templates/external_node.env.j2
+++ b/templates/external_node.env.j2
@@ -2,4 +2,10 @@ EN_ETH_CLIENT_URL="{{ eth_l1_url | mandatory }}"
 EN_MAIN_NODE_URL="{{ main_node_url | mandatory }}"
 EN_L2_CHAIN_ID="{{ l2_chain_id | mandatory }}"
 EN_L1_CHAIN_ID="{{ l1_chain_id | mandatory }}"
+{% if enable_snapshots_recovery %}
+EN_SNAPSHOTS_RECOVERY_ENABLED="true"
+EN_SNAPSHOTS_OBJECT_STORE_MODE="GCSAnonymousReadOnly"
+EN_SNAPSHOTS_OBJECT_STORE_BUCKET_BASE_URL="{{ snapshots_bucket_base_url | mandatory }}"
+{% endif %}
+
 DATABASE_URL="postgres://{{ database_username | mandatory }}:{{ database_password | mandatory }}@postgres/{{ database_name | mandatory }}"
diff --git a/templates/restore_dump.sh.j2 b/templates/restore_dump.sh.j2
index 43db63e..6f1295d 100644
--- a/templates/restore_dump.sh.j2
+++ b/templates/restore_dump.sh.j2
@@ -3,7 +3,7 @@ set -e
 
 {% if force_pg_restore %}
 pg_restore --clean --exit-on-error -j $(nproc --all) -d postgres -U $POSTGRES_USER --no-owner --no-privileges --disable-triggers --create /pg_backups/external_node_latest.pgdump
-{% else %}
+{% elif not enable_snapshots_recovery %}
 if psql -U $POSTGRES_USER -d postgres -lqt | cut -d \| -f 1 | grep -qw "{{ database_name }}"; then
     echo "Database already exists"
 else