Change type of exchange_workflow field in RecurringExchange.

[SanjayVas]

This resource type is not used by any service so this is a safe change.

Closes #182

[wfa-reviewable]

This change is 

[stevenwarejones]

Reviewed 2 of 2 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @SanjayVas)

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src/main/proto/wfa/measurement/api/v2alpha/recurring_exchange.proto line 45 at r1 (raw file):

  // Serialized `ExchangeWorkflow` for this `RecurringExchange`.
  bytes exchange_workflow = 2 [

Shouldn't you deprecate the old field and add a new?

[SanjayVas]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @stevenwarejones)

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src/main/proto/wfa/measurement/api/v2alpha/recurring_exchange.proto line 45 at r1 (raw file):
As indicated in the PR description:

This resource type is not used by any service so this is a safe change.

This resource has never been returned by any service, so we're free to make backwards-incompatible changes. Of course we should eventually have Get and List methods for every resource.

[stevenwarejones]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @SanjayVas)

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src/main/proto/wfa/measurement/api/v2alpha/recurring_exchange.proto line 45 at r1 (raw file):

Previously, SanjayVas (Sanjay Vasandani) wrote…

As indicated in the PR description:

This resource type is not used by any service so this is a safe change.

This resource has never been returned by any service, so we're free to make backwards-incompatible changes. Of course we should eventually have Get and List methods for every resource.

The name should be consistent with https://github.com/world-federation-of-advertisers/cross-media-measurement-api/blob/main/src/main/proto/wfa/measurement/api/v2alpha/exchange_step.proto#L73

[SanjayVas]

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @stevenwarejones)

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src/main/proto/wfa/measurement/api/v2alpha/recurring_exchange.proto line 45 at r1 (raw file):

Previously, stevenwarejones (Steven Ware Jones) wrote…

The name should be consistent with https://github.com/world-federation-of-advertisers/cross-media-measurement-api/blob/main/src/main/proto/wfa/measurement/api/v2alpha/exchange_step.proto#L73

Done (updated the field in ExchangeStep).

I had thought of that too, but had been avoiding the disruption. That said, we're making other breaking changes to the exchange API in this version anyway and the rename is wire-compatible change.

Note that renaming the field in this message would be inconsistent with any of our other serialized message fields which do not use the "serialized" prefix. I assume that ExchangeStep only had this prefix since the field in this message was not serialized.

[stevenwarejones]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @SanjayVas)

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src/main/proto/wfa/measurement/api/v2alpha/exchange_step.proto line 73 at r1 (raw file):

  // Denormalized `exchange_workflow` field from the ancestor
  // `RecurringExchange`.
  bytes serialized_exchange_workflow = 3 [

this field is read by clients today. That does make this a breaking change.

[SanjayVas]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @stevenwarejones)

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src/main/proto/wfa/measurement/api/v2alpha/exchange_step.proto line 73 at r1 (raw file):

Previously, stevenwarejones (Steven Ware Jones) wrote…

this field is read by clients today. That does make this a breaking change.

"Breaking change" for API protobuf definition changes refers to wire-incompatible changes. A field rename for a gRPC-only API is fully wire compatible. (Note that this wouldn't be a backwards-compatible change if we also exposed this as a REST API, as that involves JSON serialization by field name).

This may result in changes to generated language-specific code that could result in compilation breakage, but that's a separate concern.

[stevenwarejones]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @SanjayVas)