Sung,
I was thinking of v1, so you're right that manifest-list and summary are
required as of v2. The REST Spec seems to follow the v2 definition, so I
think we're somewhat implicitly requiring those fields via REST.
Kevin,
Based on the example metadata, that looks like it is not to spec, so it's
reasonable that python would reject it. If the java implementation is
allowing for that, it's likely that we're being too relaxed (possibly a
holdover from v1 parsing).
Do you know what produced the metadata?
-Dan
On Thu, Oct 17, 2024 at 9:02 AM Kevin Liu <kevin.jq....@gmail.com> wrote:
> Thanks for the additional context.
>
> My understanding is that if a Snapshot has a `summary` field, it must also
> have a corresponding `operation` key in the summary map. Is that correct?
> Based on the `SnapshotParser`, this is not enforced [1].
>
> The underlying issue in #1106 [2] is the missing `operation` field when
> the `summary` field is present.
> For example,
> ```
> "summary" : {
> "manifests-created" : "8",
> "total-records" : "26508666891",
> "added-files-size" : "3927895626752",
> "manifests-kept" : "0",
> "total-files-size" : "3927895626752",
> "added-records" : "26508666891",
> "added-data-files" : "231513",
> "manifests-replaced" : "0",
> "total-data-files" : "231513"
> }
> ```
>
> It could be the case that this particular `metadata.json` was generated
> not according to the spec.
>
> Best,
> Kevin Liu
>
>
> [1]
> https://github.com/apache/iceberg/blob/17f1c4d2205b59c2bd877d4d31bbbef9e90979c5/core/src/main/java/org/apache/iceberg/SnapshotParser.java#L124-L142
> [2] https://github.com/apache/iceberg-python/issues/1106
>
>
> On Thu, Oct 17, 2024 at 8:47 AM Sung Yun <sun...@apache.org> wrote:
>
>> Thank you for the clarification Daniel, and thank you Kevin for raising
>> this issue!
>>
>> Does that mean that we are creating component schemas that are the
>> superset of the V1 and V2 schemas? And if so, should we remove summary and
>> manifest-list from the required properties, and add manifests optional
>> property to the Snapshot schema to support both V1 and V2 Summary specs?
>> https://iceberg.apache.org/spec/#snapshots
>>
>> Or would creating separate component schemas for V1/V2 be a cleaner way
>> to align the REST spec with the table spec?
>>
>> Sung
>>
>> On 2024/10/17 15:19:23 Daniel Weeks wrote:
>> > I'm not convinced this is incorrect behavior (table spec or
>> > implementation), but it does lend to some confusion. The 'summary'
>> field
>> > is optional, which means that if a summary is not provided, you do not
>> have
>> > an associated 'operation' field. The 'operation' field is only
>> required in
>> > the context of the summary, so it's actually possible for the
>> > implementation (i.e. the tests you reference) to not have an operation.
>> >
>> > I think what is wrong here is that the REST spec marked the summary as
>> > required
>> > <
>> https://github.com/apache/iceberg/blob/8e2eb9ac2e33ce4bac8956d4e2f099444d03c0e3/open-api/rest-catalog-open-api.yaml#L2040
>> >,
>> > which is inconsistent with the table spec.
>> >
>> > On Wed, Oct 16, 2024 at 3:52 PM Anton Okolnychyi <aokolnyc...@gmail.com
>> >
>> > wrote:
>> >
>> > > Based on [1], we never persisted the operation in the summary map.
>> > > Instead, we persisted it as a top-level field in Java, which is
>> actually
>> > > NOT what the spec says. Does anyone remember cases when the operation
>> was
>> > > unknown? I personally don't.
>> > >
>> > > [1] -
>> > >
>> https://github.com/apache/iceberg/blob/17f1c4d2205b59c2bd877d4d31bbbef9e90979c5/core/src/main/java/org/apache/iceberg/SnapshotParser.java#L63
>> > >
>> > >
>> > > ср, 16 жовт. 2024 р. о 12:42 Kevin Liu <kevin.jq....@gmail.com> пише:
>> > >
>> > >> Hey folks,
>> > >>
>> > >> I’ve noticed a discrepancy between the Iceberg specification and the
>> Java
>> > >> implementation regarding the `operation` key in the `Snapshot`
>> `summary`
>> > >> field.
>> > >>
>> > >> The `Snapshot` object's `summary` dictionary includes a *required*
>> key
>> > >> named `operation`, as outlined in the spec describing Table Metadata
>> and
>> > >> Snapshots [1] and the generated OpenAPI YAML [2]. However, in the
>> Java
>> > >> implementation [3], `operation` is treated as optional. In contrast,
>> it
>> > >> remains a required field in the Python implementation [4].
>> > >> I also found that Java tests for `SnapshotParser` assert that the
>> > >> `operation` field is null. [5]
>> > >>
>> > >> Due to this discrepancy, a user reported [6] that the `metadata.json`
>> > >> file generated for an Iceberg table could not be read by PyIceberg,
>> though
>> > >> it is readable using the Iceberg Java library.
>> > >>
>> > >> How should we proceed from here? Should the Java library enforce this
>> > >> requirement? Additionally, how should we handle existing
>> `metadata.json`
>> > >> files that were generated without this field?
>> > >>
>> > >> Best,
>> > >> Kevin Liu
>> > >>
>> > >> [1] https://iceberg.apache.org/spec/#table-metadata-and-snapshots
>> > >> [2]
>> > >>
>> https://github.com/apache/iceberg/blob/8e2eb9ac2e33ce4bac8956d4e2f099444d03c0e3/open-api/rest-catalog-open-api.yaml#L2057-L2060
>> > >> [3]
>> > >>
>> https://github.com/apache/iceberg/blob/64b36999d7ff716ae2534fb0972fcc10d22a64c2/core/src/main/java/org/apache/iceberg/SnapshotParser.java#L124
>> > >> [4]
>> > >>
>> https://github.com/apache/iceberg-python/blob/7cf0c225c3cdb32ac5e390de06b7b0e4fe7de92e/pyiceberg/table/snapshots.py#L182
>> > >> [5]
>> > >>
>> https://github.com/apache/iceberg/blob/22a6b19c2e226eacc0aa78c1f2ffbdbb168b13be/core/src/test/java/org/apache/iceberg/TestSnapshotJson.java#L52
>> > >> [6] https://github.com/apache/iceberg-python/issues/1106
>> > >>
>> > >>
>> >
>>
>
