A straightforward Go exporter designed to verify WAL files backed up using WAL-G and expose the results to Prometheus.

go-task build

The container image for this exporter is built and pushed the registry using Github Actions. Alternatively, you can build it locally by executing the command below:

go-task container

The version information is stored in the VERSION file. To release a new version, follow these steps:

echo "1.0.1" > VERSION
go-task release

This process will generate a new tag v1.0.1 and push it to the Git repository, which in turn triggers a new GitHub Action to compile and deploy the container image.

his exporter is engineered to operate within a Kubernetes cluster, utilizing the sidecar Vault Injector for assistance. The essential secrets required for the exporter's operation are securely stored in Vault and are dynamically injected into the exporter's environment.

The exporter is configured using environment variables:

• WALG_EXPORTER_PORT: The port where the exporter will listen for requests.
• WALG_EXPORTER_TIMER: The time between each verification. (default: 30m)
• ENV: The environment where the exporter is running. (default: dev)
• PGCLUSTERS: A comma-separated list of Postgres clusters to verify.

Take the .env file as an example

Add the new cluster to the comma-separeted list PGCLUSTERS and restart the deployment, that will make Vault Injector to inject the new secret into the exporter.

The exporter exposes the following metrics:

• wal_g_verify_integrity_status: wal-g wal-verify integrity status - 0: OK, 1: Error, 2: Unknown
• wal_g_show_status: wal-g wal-show status - 0: OK, 1: Error, 2: Unknown
• wal_g_backup_count: number of base backups found
• wal_g_last_upload_file_s3_timestamp: last upload file timestamp UNIX epoch

• The exporter only supports S3 backups with the directory with the following structure: s3://bucket-name/postgres/walg/cluster-name-env/