Add etag support to system ComputationParticipant.

[SanjayVas]

No description provided.

[wfa-reviewable]

This change is 

[renjiezh]

Reviewed 4 of 30 files at r1, all commit messages.
Reviewable status: 4 of 30 files reviewed, 1 unresolved discussion (waiting on @SanjayVas)

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src/main/kotlin/org/wfanet/measurement/kingdom/deploy/gcloud/spanner/common/KingdomInternalException.kt line 400 at r1 (raw file):

) : KingdomInternalException(ErrorCode.MEASUREMENT_ETAG_MISMATCH, message) {
  override val context
    get() = mapOf("actual_etag" to actualETag, "request_etag" to requestETag)

Is it possible to add the participant State into the context? So that the duchy can skip the rpc call if it is duplicated.

[SanjayVas]

Reviewable status: 4 of 30 files reviewed, 1 unresolved discussion (waiting on @renjiezh)

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src/main/kotlin/org/wfanet/measurement/kingdom/deploy/gcloud/spanner/common/KingdomInternalException.kt line 400 at r1 (raw file):

Previously, renjiezh wrote…

Is it possible to add the participant State into the context? So that the duchy can skip the rpc call if it is duplicated.

The context should just be the variables of the error message. It shouldn't be used to pass resource info. If the caller wants the state, it should do another read.

[renjiezh]

Reviewed 26 of 30 files at r1, 2 of 2 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @SanjayVas)

[SanjayVas]

Depends on #1664

[stevenwarejones]

Reviewed 25 of 30 files at r1, 2 of 2 files at r2, 4 of 4 files at r3, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @SanjayVas)

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src/main/kotlin/org/wfanet/measurement/kingdom/deploy/gcloud/spanner/common/ETags.kt line 22 at r3 (raw file):

import org.wfanet.measurement.gcloud.common.toInstant

object ETags {

why this duplicate object? that just calls common?

[SanjayVas]

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

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src/main/kotlin/org/wfanet/measurement/kingdom/deploy/gcloud/spanner/common/ETags.kt line 22 at r3 (raw file):

Previously, stevenwarejones (Steven Ware Jones) wrote…

why this duplicate object? that just calls common?

This version is for com.google.cloud.Timestamp, which is currently only used for Spanner. The top-level common shouldn't have that dependency

[stevenwarejones]

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