Automated DynamoDB Backups ⚡️

Usage

1. Install the Serverless Framework:

   $ npm install -g serverless

2. Install this repository as a Serverless project:

   $ sls install --url https://github.com/alexdebrie/serverless-dynamodb-backups && cd serverless-dynamodb-backups

3. Update the required configuration in the custom block of serverless.yml.

4. Deploy!

   $ sls deploy

Configuration

There are three ways you can specify which tables to backup:

1. Regex on all tables in region. The function can call the ListTables API and include all tables whose name matches a given regular expression. This is the most dynamic configuration, as you won't need to redeploy this function every time you add a new DynamoDB table. This works best if you have a specified naming scheme for your tables, such as prefixing all tables with the stage. Then you can add a pattern of "^(prod-)." to match all tables that start with prod-. To use this method, put your regular expression in the tableRegex property.

2. Specify multiple table names in an included file. If you have a list of tables you want to back up, you can place their names in a local file and specify the name of the file in the tableFile property. The format must be valid JSON that is a list of strings. A tables.json file is included in this repo as an example.

3. Specify a single table via environment variable. If you only have one table to backup, you can specify its name via the tableName property.

In addition to the table configuration, there is also the following configuration:

• backupRate - required - The schedule on which you want to backup your table. You can use either rate syntax (rate(1 hour)) or cron syntax (cron(0 12 * * ? *)). See here for more details on configuration.

• slackWebhook - optional - An HTTPS endpoint for an incoming webhook to Slack. If provided, it will send success + error messages to a Slack channel when it runs.

• backupRemovalEnabled - optional - Setting this value to true will enable cleanup of old backups. See the below option, backupRetentionDays, to specify the retention period. By default, backup removal is disabled.

• backupRetentionDays - optional - Specify the number of days to retain old snapshots. For example, setting the value to 2 will remove all snapshots that are older then 2 days from today.

Notes

• As of 12/11/2018, DynamoDB backups aren't working for all tables. It appears to be tables created after a certain time, though I don't know what that cutoff is. If your table is ineligible, you'll get a ContinuousBackupsUnavailableException.
• The botocore package bundled with Lambda doesn't include the new features announced at reInvent. As a result, I added the dynamodb data directory from a more recent version of botocore and set the AWS_DATA_PATH environment variable to recognize it.

Potential improvements

• Better control on notifications? We could implement email or SMS messages, as well as the ability to only notify on failures.