Skip to content

OpenAPI: Add CatalogObjectIdentifier schema #16144

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
stevenzwu wants to merge 3 commits into
base: main
Choose a base branch
from
+23 −0
Open

OpenAPI: Add CatalogObjectIdentifier schema #16144

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
e6a0323
OpenAPI: Add CatalogObjectIdentifier and CatalogObjectType schemas
stevenzwu Apr 29, 2026
9f16004
OpenAPI: Drop the shared CatalogObjectType schema
stevenzwu May 8, 2026
9c2ed0a
OpenAPI: Reword CatalogObjectIdentifier example list as non-exhaustive
stevenzwu May 15, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 18 additions & 0 deletions open-api/rest-catalog-open-api.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -106,6 +106,24 @@ class TableIdentifier(BaseModel):
name: str


class CatalogObjectIdentifier(RootModel[list[str]]):
"""
Reference to a catalog object (table, view, or namespace) as an ordered list of hierarchical levels. The object kind is determined by context (e.g. the endpoint or a companion CatalogObjectType discriminator), not by the identifier structure alone.
"""

root: list[str] = Field(
...,
description='Reference to a catalog object (table, view, or namespace) as an ordered list of hierarchical levels. The object kind is determined by context (e.g. the endpoint or a companion CatalogObjectType discriminator), not by the identifier structure alone.',
examples=[['accounting', 'tax', 'paid']],
)


class CatalogObjectType(RootModel[Literal['table', 'view', 'namespace']]):
root: Literal['table', 'view', 'namespace'] = Field(
..., description='The type of a catalog object.\n'
)


class PrimitiveType(RootModel[str]):
root: str = Field(..., examples=[['long', 'string', 'fixed[16]', 'decimal(10,2)']])

Expand Down
21 changes: 21 additions & 0 deletions open-api/rest-catalog-open-api.yaml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2267,6 +2267,27 @@ components:
type: string
nullable: false

CatalogObjectIdentifier:
description:
Reference to a catalog object (table, view, or namespace) as an
Copy link
Copy Markdown
Contributor

@pvary pvary May 15, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Maybe add "for example" to the list, so we don't need to maintain it if we add functions, indexes etc.

Copy link
Copy Markdown
Contributor Author

@stevenzwu stevenzwu May 15, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Good catch. Reworded to "Reference to a catalog object (for example, table, view, or namespace)" so the list reads as illustrative and doesn't need to be maintained as new kinds (functions, indexes, etc.) are added. Pushed in 9c2ed0a.

ordered list of hierarchical levels.
The object kind is determined by context (e.g. the endpoint or a
companion CatalogObjectType discriminator), not by the identifier
structure alone.
type: array
items:
type: string
Copy link
Copy Markdown
Contributor

@flyrain flyrain May 12, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Do we apply any constraints on the table/view/namespace name? For example, no slash(/) is allowed. Given we didn't specify any constraint on the table identifier, it's not a blocker for this PR. We can work on that as a followup. We can also discuss whether we could avoid any constraints in IRC, and relying on the implementations(catalogs, engines) to cast their options.

Copy link
Copy Markdown
Member

@RussellSpitzer RussellSpitzer May 12, 2026 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We have previously let folks do whatever they want in string fields and left it up to the implementation to decide whether or not that string is invalid.

example: [ "accounting", "tax", "paid" ]

CatalogObjectType:
type: string
description: |
The type of a catalog object.
enum:
- table
- view
- namespace
Copy link
Copy Markdown
Contributor

@danielcweeks danielcweeks Apr 30, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think there was an open question about how and where this would actually be used. Introducing type without context leaves me unsure if it's inline with how we want to reference types.

For example, you could have the resolve endpoint return:

[
  [ identifier, type, metadata ] 
  [ identifier, type, metadata ]
  ...
]

or:

tables: <identifier, metadata>
views: <identifier, metadata>
namespaces: <identifier, metadata>

The first approach requires type, but might impact backward compatibility. If we introduce a new type (e.g. function) then clients would break if they don't understand the type. The second approach allows you to extend the response object without modifying the original fields.

I'd like to see how it would be referenced in context.

Copy link
Copy Markdown
Contributor Author

@stevenzwu stevenzwu Apr 30, 2026 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I updated the design doc for the resolve endpoint and included example request and response payload json
https://docs.google.com/document/d/1VW5hgaaajRWtp5KbOU3s83YyoyPi5WOSvHtoJ_yXzJs/edit?tab=t.0#heading=h.z0wh4486aab5

Here is the usage from the events endpoint spec PR. It is used as an event filter in the request body.
https://github.com/apache/iceberg/pull/12584/changes#r3170935023

Copy link
Copy Markdown
Contributor

@c-thiel c-thiel May 4, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

In the Events Endpoint having this explicit type filter is valuable I believe which is why we introduced this type there.
Shouldn't clients be tolerant in both cases - for unknown enum variants as well as unknown fields?

Copy link
Copy Markdown
Contributor

@danielcweeks danielcweeks May 7, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I don't think it's as easy as saying the clients should tolerate it. If you add new types, generated parsers will break when they encounter something that wasn't originally enumerated. That's why the type approach feels brittle.

@rdblue might have an opinion here since he originally brought it up in the discussion.

Copy link
Copy Markdown
Contributor Author

@stevenzwu stevenzwu May 7, 2026 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

To clarify Dan's framing, here are the two response shapes he sketched:

Shape A — flat array of typed records, each carrying its own discriminator:

[
  { "identifier": [...], "type": "table", "metadata": {...} },
  { "identifier": [...], "type": "view",  "metadata": {...} }
]

Shape B — separate bucket per kind:

{
  "tables":     [ { "identifier": [...], "metadata": {...} }, ... ],
  "views":      [ ... ],
  "namespaces": [ ... ]
}

Dan's critique: Shape A's type is a closed enum, so adding a new value (e.g. function) breaks generated parsers on old clients.

The Shape B counter has its own forward-compat hole — and a worse one. An old client that doesn't know the materialized_views key never iterates that field, so the identifier just vanishes from the resolved set; the client can't even distinguish "didn't resolve" from "resolved to a kind I don't recognize." A parse error at least tells you something is wrong.

The design doc actually already proposes a hybrid that handles the top-level concern: per-category typed arrays (relations: [...], future functions: [...]) bucket the major categories Shape-B style, while inside each bucket the result is a flat record that carries an object-type discriminator Shape-A style:

{
  "relations": [
    {
      "identifier": ["analytics", "daily_sales_view"],
      "status": "loaded",
      "result": { "object-type": "view", "view": { /* LoadViewResult */ } }
    }
  ]
}

Adding a new top-level category (functions) is safe: generators silently ignore unknown top-level fields. The forward-compat risk only lives on result.object-type — that's where adding materialized-view later could break old codegen if it's a closed enum.

Proposal: spec result.object-type (and CatalogObjectType itself) as type: string with documented values, not a closed enum.

ResolveResult:
  type: object
  required: [object-type]
  properties:
    object-type:
      type: string
      description: |
        Object kind. Currently one of: table, view, materialized-view.
        Clients should fall through to a default handler for unrecognized values.
    table:
      $ref: '#/components/schemas/LoadTableResult'
    view:
      $ref: '#/components/schemas/LoadViewResult'

What this buys:

  • No codegen breakage. datamodel-codegen emits object_type: str, not Literal[...]. Pydantic, Jackson with default config, Go's encoding/json, etc. all accept arbitrary strings.
  • No silent data loss. Every resolved identifier still has a row with identifier, status, and result. A hand-written client switches on known object-type values and falls through unknown ones to a "skip / report unsupported" branch with full visibility.
  • Schema still documents the valid set. The description carries the enumeration; humans and IDE tooltips see it. We can validate server-side conformance in our own CI without imposing closed-enum behavior on every generated client.
  • Filter input keeps the closed enum. CatalogObjectType as enum on request bodies (e.g. the events filter) is fine — the client picks values from its own schema; the server tolerates older filter sets.

Prior art for this pattern:

  • Iceberg REST already uses it internally. The most-evolved discriminator fields in this spec are declared as plain type: string, not closed enums, with valid values listed via discriminator.mapping:

    • MetadataUpdate.action (BaseUpdate) — the set has grown over time (add-encryption-key, remove-encryption-key, remove-schemas, remove-partition-specs, enable-row-lineage, set-partition-statistics, remove-partition-statistics, …) without breaking clients with stale schemas.
    • TableRequirement.type — same pattern.
    • ViewRequirement.type — same pattern.

    Closed enum in this spec is reserved for stable sets (FileFormat, SortDirection, NullOrder, SnapshotRefType) that aren't expected to grow casually. CatalogObjectType is clearly in the first group — materialized-view and function are already foreseen.

Copy link
Copy Markdown
Contributor Author

@stevenzwu stevenzwu May 8, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Updated proposal: drop the shared CatalogObjectType and split it into two narrower closed enums, one per use case.

Resolve response: closed enum [table, view, materialized-view]. The relations universe is small enough to enumerate, and pre-listing materialized-view even before MV is implemented means clients ship with the value already in their schema — no breakage when a server starts returning it. Trade-off is a maintenance commitment: adding a 4th relational type later (e.g. external-table, streaming-view) becomes a coordinated spec change rather than a transparent extension.

Events filter: closed enum on the request body. Client picks values from its own schema; server rejects unknowns with a clear error. No codegen-breakage concern, since the field never carries server-originated values back to old clients.

Events response: no separate object-type discriminator needed. The events spec (#12584) already defines an operation-type enum (create-table, drop-view, etc.) on each event, which implicitly encodes the kind of object the event is about.

Naming: two independent named schemas — RelationType near the resolve endpoint, EventObjectType (or similar) near events. Decoupling is the point: each enum evolves on its own schedule, which is the property the shared CatalogObjectType couldn't deliver.


PrimitiveType:
type: string
example:
Expand Down
Loading