use lmdb by default if DATABASE_ENGINE not defined

docs adverts lmdb can become corrupted on power outages

https://garagehq.deuxfleurs.fr/documentation/reference-manual/configuration/#db_engine

.env.sample

@@ -11,6 +11,7 @@ SECRET_RPC_SECRET_VERSION=v1 # length=32 charset=hex
 # supported and requires deleting the existing cluster layout metadata.
 REPLICATION_FACTOR=2
 
+DATABASE_ENGINE=lmdb
 CONSISTENCY_MODE=consistent
 METADATA_FSYNC=false
 DATA_FSYNC=false
@@ -27,4 +28,4 @@ BLOCK_SIZE=1MiB # only increase if there is a fast network connection between no
 #LOCAL_FOLDER_DATA=/path/on/docker/host
 
 ## Enable Full Data Backups (not just metadata)
-# COMPOSE_FILE="$COMPOSE_FILE:compose.fullbackup.yml"
+# COMPOSE_FILE="$COMPOSE_FILE:compose.fullbackup.yml"

abra.sh

@@ -1 +1 @@
-export GARAGE_CONF_VERSION=v4
+export GARAGE_CONF_VERSION=v5

garage.toml.tmpl

@@ -1,6 +1,6 @@
 metadata_dir = "/var/lib/garage/meta"
 data_dir = "/var/lib/garage/data"
-db_engine = "lmdb"
+db_engine = "{{ if env "DATABASE_ENGINE" }}{{ env "DATABASE_ENGINE" }}{{ else }}lmdb{{ end }}"
 metadata_auto_snapshot_interval = "6h"
 
 replication_factor = {{ env "REPLICATION_FACTOR" }}
@@ -26,4 +26,4 @@ bootstrap_peers = [
 [s3_api]
 s3_region = "garage"
 api_bind_addr = "[::]:3900"
-root_domain = ".s3.garage"
+root_domain = ".s3.garage"

renovate.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "config:recommended"
+  ]
+}