Google-cloud-go: pubsub:ExpirationPolicy is not included in SubscriptionConfig

[iluminae]

Client

PubSub

Feature

Ability to set ExpirationPolicy on pubsub SubscriptionConfig{} object. Currently, ExpirationPolicy cannot be set on the subscription. This feature exists in the API and Google Cloud Console when creating a subscription.

here it is in the protobuf:
https://github.com/google/go-genproto/blob/master/googleapis/pubsub/v1/pubsub.pb.go#L953

[jadekler]

@sduskis @kir-titievsky @kamalaboulhosn

[sduskis]

@jadekler, it would indeed be awesome to have expiration policy and oidc_token in the pub/sub subscription CRUD.

[odeke-em]

For some status updates, we are almost finished with this feature:

• [x] ExpirationPolicy added with https://github.com/googleapis/google-cloud-go/commit/06e163b5f181cb98f6179f966b1b88cf03b491ec
• [ ] OpenIDConnectToken pending https://code-review.googlesource.com/c/gocloud/+/40771

[lc-caigwatkin]

This is a good addition, however, I am not sure how I would use this feature to set the expiration policy to "never expire," a feature which is available through the GCP UI. Did I miss something in the documentation?

[odeke-em]

Great question @lc-caigwatkin! So the GCP UI and gcloud cli use a sentinel value of "never" and we are going to mimick the same by providing a NeverExpire constant in a CL coming up shortly.
Thus code to do this will look like this:

package main

import (
    "context"
    "log"
    "time"

    "cloud.google.com/go/pubsub"
)

func main() {
    ctx := context.Background()
    client, err := pubsub.NewClient(ctx, "odeke-sandbox")
    if err != nil {
        log.Fatalf("Failed to create client: %v", err)
    }
    defer client.Close()

    topic, _ := client.CreateTopic(ctx, "issue-1361-t")

    // Create the new subscription
    subName := "sub-1361"
    _, _ = client.CreateSubscription(ctx, subName, pubsub.SubscriptionConfig{
        Topic:            topic,
        AckDeadline:      30 * time.Second,
        ExpirationPolicy: 25 * time.Hour,
    })

    gotSub := client.Subscription(subName)
    cfg, err := gotSub.Config(ctx)
    if err != nil {
        log.Fatalf("Failed to retrieve the config: %v", err)
    }
    log.Printf("Config: %+v\n", cfg)

    <-time.After(1 * time.Minute)
    // Now update it.
    sCfg := pubsub.SubscriptionConfigToUpdate{
        ExpirationPolicy: pubsub.NeverExpire,
    }
    updated, _ := gotSub.Update(ctx, sCfg)
    log.Printf("Updated: %+v\n", updated)
}

and you'll be able to verify on the UI that ExpirationPolicy is set to NEVER expire.

[lc-caigwatkin]

Thanks @odeke-em

From looking at your example, is it best practice to first create a subscription that is not set to never expire before updating it as such? Or would simply creating it with pubsub.NeverExpire be just as good?

[odeke-em]

That example is just to show you that you can update it. But from the get-go you'll be able to set it to pubsub.NeverExpire so during creation too.

[lc-caigwatkin]

Excellent! Thanks for your explanation

[jadekler]

For posterity: https://code-review.googlesource.com/c/gocloud/+/41211

[odeke-em]

I believe this issue can now be closed and all CLs have been merged.

[odeke-em]

/cc @hongalex