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Version: v0.1.1

Getting started

A first inventory against a local MinIO, on your machine, in a few minutes. No cluster, no cloud account.

1. Build the binary​

git clone https://github.com/fyannk/pgObjectStoreViewer
cd pgObjectStoreViewer
make build

You need Go 1.26+. Docker is needed for step 2 and for integration tests, not for the viewer itself.

2. Start a local S3​

docker run --rm --detach --name osv-minio \
  --publish 9000:9000 \
  --env MINIO_ROOT_USER=local-access \
  --env MINIO_ROOT_PASSWORD=local-secret-value \
  minio/minio server /data

Create a bucket and a read-only user. Using mc from a container:

export MC_HOST_local=http://local-access:local-secret-value@127.0.0.1:9000
docker run --rm --network host --env MC_HOST_local \
  minio/mc mb local/backups

3. Put a Barman repository in it​

If you already have a Barman Cloud repository, mirror a copy of it under backups/repository/. Otherwise, the repository's integration harness builds a genuine Barman 3.19.1 repository from a real PostgreSQL instance:

make test-s3

That target starts pinned MinIO and PostgreSQL containers, runs a real barman-cloud-backup and WAL archive journey, and asserts the resulting inventory. It is the fastest way to see honest evidence end to end, and it is also the reference for what a valid layout looks like:

backups/repository/<server>/base/<backup-id>/backup.info
backups/repository/<server>/base/<backup-id>/data.tar.gz
backups/repository/<server>/wals/<timeline+log>/<wal-name>
backups/repository/<server>/wals/<timeline>.history

4. Mount credentials as files​

Static credentials are accepted only as mounted files — that is not configurable:

mkdir -p /tmp/osv-credentials
printf '%s' 'local-access'       > /tmp/osv-credentials/access-key-id
printf '%s' 'local-secret-value' > /tmp/osv-credentials/secret-access-key
chmod 0400 /tmp/osv-credentials/*

In a real deployment these are keys of a read-only Secret volume, and the credential itself is scoped to list and get under the prefix only — see the policy reference.

5. Run the viewer​

REPOSITORY_FORMAT=barman-cloud \
PROVIDER=s3 \
DESTINATION_PATH=s3://backups/repository \
ENDPOINT_URL=http://127.0.0.1:9000 \
AWS_REGION=us-east-1 \
AWS_ACCESS_KEY_ID_FILE=/tmp/osv-credentials/access-key-id \
AWS_SECRET_ACCESS_KEY_FILE=/tmp/osv-credentials/secret-access-key \
CATALOG_REFRESH_INTERVAL=30s \
./bin/objectstoreviewer

Then:

curl -s localhost:3000/healthz   # process liveness
curl -s localhost:3000/readyz    # ready once a prefix-scoped list succeeds
open http://localhost:3000/      # the inventory page

CATALOG_REFRESH_INTERVAL=30s is the minimum accepted value and makes experimenting quicker; the default is 5m.

6. Read the page honestly​

Things worth noticing, because they are the product rather than rough edges:

  • The first render may be unknown. Until the first background scan completes there is no generation, so totals are null — not 0.
  • Totals are exact only after a complete scan. If you set MAX_OBJECTS_PER_SCAN low enough to truncate, totals become unknown.
  • An empty prefix is ready. Point DESTINATION_PATH at a prefix that does not exist and the viewer becomes ready and reports a complete, empty inventory. Ready plus empty usually means a wrong prefix.
  • A stopped MinIO does not erase evidence. Stop the container and watch the next refresh fail: the last complete snapshot is retained and marked stale, and dependent states go unknown.
docker stop osv-minio     # watch /readyz and the freshness panel
docker start osv-minio    # the next complete scan clears the staleness

7. Explore WAL evidence​

Open http://localhost:3000/wals and filter by server, class, timeline, and WAL-name range. Classes are segment, partial, history, backup-history, duplicate, and unknown.

If continuity reads unknown, that is usually a correct answer — the segment size or PostgreSQL version context was unavailable, two complete representations of one position exist, or a safety ceiling truncated the evidence. See the evidence model.

8. Clean up​

docker rm -f osv-minio
rm -rf /tmp/osv-credentials

Next steps​