Ben McClelland
ef8f1b987f
STILL NOT FIXED: in backend/meta/sidecar.go CommitMetadata() Between pathIno(dataPath) != myIno returning false (check passes) and os.Rename executing, another goroutine can win link() and install a new inode at dataPath. This goroutine then proceeds to rename its stale attributes over the winner's freshly committed ones. The comment's safety argument — "the true winner's CommitMetadata will overwrite any partially committed attributes before it finishes" — only holds if the winner runs entirely after this goroutine's renames. If the winner already finished its renames before this goroutine's stale os.Rename executes, the loser's data corrupts the final metadata silently. This is a fundamental TOCTOU problem. There is no POSIX syscall for "rename only if this inode still owns the destination", so it can't be fixed with filesystem operations alone. The real fix would require serializing CommitMetadata calls per object ---- Previously, StoreAttribute wrote metadata (checksums, etc.) directly to the final per-object sidecar path during upload. Concurrent uploads of the same object would race to write into the same directory, causing one upload's metadata to be silently overwritten by another's data file, or vice-versa. On Linux, O_TMPFILE fd-number reuse made this worse: after link() closed the fd, the inode-number slot could be immediately reused by a different goroutine. Fix by staging sidecar metadata in a per-upload temporary directory named .sgwtmp.<pid>.<inode> instead of the final path, then atomically committing it after the data file has been linked. tmpSidecarID() identifies an in-flight upload by PID + inode (Unix) or PID + temp filename (Windows), matching the token produced by tmpfile.SidecarToken() in the posix backend so staging and commit find the same directory. StoreAttribute now writes attributes into the inode-keyed temp sidecar dir with a retry loop (up to 5 attempts) to handle the inode-reuse edge case where a concurrent CommitMetadata RemoveAll races with a fresh MkdirAll on the same directory name. CommitMetadata moves the staged attributes to the final object path one-by-one via atomic rename. Before each rename it re-verifies that the data file's inode still matches the token; if not, a later concurrent upload won the race and this goroutine aborts cleanly, leaving the winner's metadata intact.
The Versity S3 Gateway:
A High-Performance S3 Translation Service
Binary release builds
Download latest release
| Linux/amd64 | Linux/arm64 | MacOS/amd64 | MacOS/arm64 | BSD/amd64 | BSD/arm64 |
|---|---|---|---|---|---|
| ✔️ | ✔️ | ✔️ | ✔️ | ✔️ | ✔️ |
Use Cases
- Turn your local filesystem into an S3 server with a single command!
- Proxy S3 requests to S3 storage
- Simple to deploy S3 server with a single command
- Protocol compatibility in
posixallows common access to files via posix or S3 - Simplified interface for adding new storage system support
WebGUI
Get more details about the new (optional) WebGUI management/explorer here: https://github.com/versity/versitygw/wiki/WebGUI
Static Website Hosting
Serve S3 buckets as static websites with index documents, custom error pages, and routing rules.
Enable a separate website endpoint with --website :8090 --website-domain example.com for virtual-host style routing (blog.example.com serves bucket blog, example.com serves bucket example.com).
When --website-domain is omitted, catch-all mode is used: the full hostname becomes the bucket name (name your buckets as FQDNs, e.g. blog.example.com).
See Global Options for all --website-* flags.
News
Check out latest wiki articles: https://github.com/versity/versitygw/wiki/Articles
Mailing List
Keep up to date with latest gateway announcements by signing up to the versitygw mailing list.
Documentation
See project documentation on the wiki.
Need help?
Ask questions in the community discussions.
Contact Versity Sales to discuss enterprise support.
Overview
Versity Gateway, a simple to use tool for seamless inline translation between AWS S3 object commands and storage systems. The Versity Gateway bridges the gap between S3-reliant applications and other storage systems, enabling enhanced compatibility and integration while offering exceptional scalability.
The server translates incoming S3 API requests and transforms them into equivalent operations to the backend service. By leveraging this gateway server, applications can interact with the S3-compatible API on top of already existing storage systems. This project enables leveraging existing infrastructure investments while seamlessly integrating with S3-compatible systems, offering increased flexibility and compatibility in managing data storage.
The Versity Gateway is focused on performance, simplicity, and expandability. The Versity Gateway is designed with modularity in mind, enabling future extensions to support additional backend storage systems. At present, the Versity Gateway supports any generic POSIX file backend storage, Versity’s open source ScoutFS filesystem, Azure Blob Storage, and other S3 servers.
The gateway is completely stateless. Multiple Versity Gateway instances may be deployed in a cluster to increase aggregate throughput. The Versity Gateway’s stateless architecture allows any request to be serviced by any gateway thereby distributing workloads and enhancing performance. Load balancers may be used to evenly distribute requests across the cluster of gateways for optimal performance.
The S3 HTTP(S) server and routing is implemented using the Fiber web framework. This framework is actively developed with a focus on performance. S3 API compatibility leverages the official aws-sdk-go-v2 whenever possible for maximum service compatibility with AWS S3.
Getting Started
See the Quickstart documentation.
Run the gateway with posix backend:
mkdir /tmp/vgw /tmp/vers
ROOT_ACCESS_KEY="testuser" ROOT_SECRET_KEY="secret" ./versitygw --port :10000 --iam-dir /tmp/vgw posix --versioning-dir /tmp/vers /tmp/vgw
This will enable an S3 server on the current host listening on port 10000 and hosting the directory /tmp/vgw with older object versions in /tmp/vers. It's fine if both of these directories are within the same filesystem. The --iam-dir option enables simple JSON flat file accounts for testing.
To get the usage output, run the following:
./versitygw --help
The command format is
versitygw [global options] command [command options] [arguments...]
The global options are specified before the backend type and the backend options are specified after.
Testing & Production Readiness
VersityGW is battle-tested and production-ready. Every pull request must pass our comprehensive test suite before it can be reviewed or merged. All code reviews are done by at least one human in the loop. LLMs may be used to augment the review process, but are never the sole reviewer or decision maker. See Testing for high level testing documentation.
Comprehensive Test Coverage
Our multi-layered testing strategy includes:
- Go Unit Test Files - Extensive unit tests with race detection and code coverage analysis covering core functionality, edge cases, and error handling.
- Integration Test Scripts - Real-world scenario testing across multiple backends (POSIX, S3, Azure) and configurations.
- Functional/Regression Tests - End-to-end SDK tests validating complete workflows including full-flow operations, POSIX-specific behavior, and IAM functionality populated with regression tests as issues are addressed.
- Static Analysis - Static Analysis checks using staticcheck.
- System Tests - Protocol-level validation using industry-standard S3 clients:
- AWS CLI - Official AWS command-line tools
- s3cmd - Popular S3 client
- Direct REST API testing with curl for request/response validation
- Security Testing - Both HTTP and HTTPS configurations tested. Vulnerability scanning with govulncheck. And regular dependency updates with dependabot.
- Compatibility Testing - Multiple backends, versioning scenarios, static bucket modes, and various authentication methods.
Run the gateway in Docker
Use the published image like the native binary by passing CLI arguments:
docker run --rm versity/versitygw:latest --version
See Docker for more documentation for running within Docker.
Run on Kubernetes
A Helm chart is provided to easily run Versity in Kubernetes environments:
helm install versitygw oci://ghcr.io/versity/versitygw/charts/versitygw
Please refer to the chart's README for more information and configuration parameters.
Versity gives you clarity and control over your archival storage, so you can allocate more resources to your core mission.
Contact
info@versity.com
+1 844 726 8826
@versitysoftware
