This project provides a cloud-based backup service to SolarNode.

The service supports the following settings:

All values are required. The S3 Path value can be empty. The Key values are Configuration Admin keys for the net.solarnetwork.node.backup.s3.S3BackupService PID. That means you can configure these in a conf/services/net.solarnetwork.node.backup.s3.S3BackupService.cfg file on the node if you don't want to manage them via the Setup GUI. For example:

# Sample conf/services/net.solarnetwork.node.backup.s3.S3BackupService.cfg file

accessToken = 123abc
accessSecret = 234bcd
regionName = us-east-1
bucketName = mybucket
storageClass = STANDARD_IA

Backups are stored using a shared object structure, where individual backup resources are named after the SHA256 digest of their content with a backup-data/ prefix added. Metadata about each backup (for example a listing of the resources included in the backup) is then stored as an object named with the node ID and backup timestamp with a backup-meta/ prefix added. The object names use this pattern:

Here's a an example listing of the objects stored in S3 after a couple of backups have finished:

The shared aspect of the backups means that individual backup-data/ objects can be referenced by multiple backups. Once a resource is backed up to S3, it won't be uploaded to S3 again in future backups unless the resource changes.

The shared aspect of the backups also means that multiple nodes can be configured to save backup data to the same S3 location. In that situation the same resources across the nodes will only be stored once in backup-data/, and referenced by their respective backup metadata.

The backup metadata is a JSON document that defines some general information about the backup along with a list of all resources included in the backup. Each resource contains a SolarNode-specific providerKey representing the provider of the resource, a backupPath defined by that provider, and an objectKey that points to the S3 object that contains the data for that resource.

{
  "complete": true,
  "date": 1507093749000,
  "key": "node-163-backup-20171004T180909",
  "nodeId": 163,
  "resourceMetadata": [
    {
      "backupPath": "net.solarnetwork.node.backup.FileBackupResourceProvider/app/main/net.solarnetwork.node.datum.samplefilter-1.1.0.jar",
      "modificationDate": 0,
      "objectKey": "solarnode-backups/backup-data/45a303aae39ad8e53fcf38162bf718cd7bc0b70d1344eaae619d7e9f665cc58d",
      "providerKey": "net.solarnetwork.node.backup.FileBackupResourceProvider"
    },
    {
      "backupPath": "net.solarnetwork.node.setup.impl.DefaultKeystoreService/node.jks",
      "modificationDate": 1471324554000,
      "objectKey": "solarnode-backups/backup-data/48b811a37e26ffba3743b2eb421c0c10d1772776c29ddceb83eb7b25c203b9b1",
      "providerKey": "net.solarnetwork.node.setup.impl.DefaultKeystoreService"
    },
    {
      "backupPath": "net.solarnetwork.node.settings.ca.CASettingsService/settings.csv",
      "modificationDate": -1,
      "objectKey": "solarnode-backups/backup-data/9754cb0ac2df3891fe1158905a307acc312dd2550fcb75926f7eaff2778afba5",
      "providerKey": "net.solarnetwork.node.settings.ca.CASettingsService"
    }
  ]
}

The metadata JSON object has the following properties:

The resourceMetadata array contains a list of JSON objects, each of which represents an individual backup resource. The SolarNode backup service does not actually control what should be included in any given backup, nor understand what any resource represents. Instead it relies on SolarNode plugins to contribute Backup Resource Provider services at runtime, each of which contributes a set of resources to the backup, and can restore those resources when asked. Thus to understand what a given backup resource actually is, you need to consult the documentation of the Backup Resource Provider that provided the resource, which is uniquely defined by a key.

Each JSON object has the following properties: