Thanks for starting the thread Rahul ! +1 to the proposal On Wed, Sep 2, 2026 at 3:37 PM Daniel Weeks <[email protected]> wrote:
> Hey Rahul, > > Thanks for the proposal. Minor comments on the spec, but overall looks > great. > > On Wed, Sep 2, 2026 at 3:01 PM Ryan Blue <[email protected]> wrote: > >> This looks like a good proposal to me. Thanks, Rahul. >> >> On Wed, Sep 2, 2026 at 9:05 AM Alex Dutra <[email protected]> wrote: >> >>> Hi Rahul, >>> >>> I really like your proposal. Some time ago, I attempted to identify >>> clients in Polaris by analyzing their User-Agent and X-Client-Version >>> headers, but I quickly discovered that this approach was far more >>> complicated and unreliable than I had expected [1]. I think the >>> standardization that you are proposing here will finally make it >>> doable. >>> >>> Thanks, >>> Alex >>> >>> [1]: https://github.com/apache/polaris/pull/4236 >>> >>> On Tue, Sep 1, 2026 at 6:26 PM rahul mahadev <[email protected]> >>> wrote: >>> > >>> > Hi all, >>> > >>> > I'd like to propose a recommended User-Agent format for REST catalog >>> > clients, so a client identifies itself to a catalog in a consistent, >>> > parseable way. >>> > >>> > Today it's inconsistent: >>> > - iceberg-java sends no User-Agent by default (it's opt-in via config). >>> > - pyiceberg sends "PyIceberg/<version>", iceberg-rust >>> "iceberg-rs/<version>", >>> > iceberg-go "GoIceberg/<version>" basically all different naming. >>> > - X-Client-Version carries the library version in Java/Python but the >>> REST >>> > spec version in Rust/Go. >>> > - None of this is described in the spec. >>> > >>> > That makes it hard for a catalog operator to tell what's actually >>> calling, >>> > which matters for observability, debugging, and support. >>> > >>> > Proposal: use the standard User-Agent header (RFC 7231) i.e. >>> whitespace- >>> > separated product/version tokens, most specific first (engine -> >>> > integration -> Iceberg library -> runtime), with an optional >>> parenthesized >>> > comment for extra context. Example: >>> > >>> > Spark/4.0.0 iceberg-spark/1.9.0 iceberg-java/1.9.0 (scala/2.13.16) >>> > >>> > The Iceberg library token is the one piece every client can supply, so >>> it >>> > should always be present. The header is optional and informational >>> only: >>> > servers must not reject on it, must not use it for auth or trust >>> decisions, >>> > and it is not a capability negotiation mechanism. >>> > >>> > Draft PR with the spec change: >>> > https://github.com/apache/iceberg/pull/17727 >>> > >>> > If the format looks right, the follow-ups would be conforming the >>> client >>> > libraries (java / python / rust / go) to emit it. >>> > >>> > A few open questions: >>> > 1. Should we also reconcile X-Client-Version (library vs spec version >>> > across clients), or leave it and treat User-Agent as the canonical >>> > identity going forward? >>> > 2. Naming: keep the existing library names (PyIceberg, iceberg-rs, >>> > GoIceberg) or converge on one scheme (iceberg-<lang>)? >>> > 3. Is a separate environment token (e.g. prod/staging) useful, or does >>> > that belong in the comment? >>> > 4. Any other fields we want to capture ? >>> > >>> > Feedback welcome. >>> > >>> > Thanks, >>> > Rahul Mahadev (github: rahulsmahadev) >>> >>
