func DeleteBucketIfExists()

in internal/testutil/storage_cleaner.go [65:131]
50 lines of code
14 McCabe index (conditional complexity)

func DeleteBucketIfExists(ctx context.Context, client *storage.Client, bucket string) error {
	b := client.Bucket(bucket)

	// Check if the bucket does not exist, return nil.
	if _, err := b.Attrs(ctx); err != nil {
		return nil
	}

	// Delete all of the elements in the already existent bucket, including noncurrent objects.
	it := b.Objects(ctx, &storage.Query{
		// Versions true to output all generations of objects.
		Versions: true,
	})
	for {
		attrs, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return fmt.Errorf("Bucket.Objects(%q): %v", bucket, err)
		}
		obj := b.Object(attrs.Name)
		// Objects with a hold must have the hold released
		if attrs.EventBasedHold || attrs.TemporaryHold {
			if _, err := obj.Update(ctx, storage.ObjectAttrsToUpdate{
				TemporaryHold:  false,
				EventBasedHold: false,
			}); err != nil {
				return fmt.Errorf("Bucket(%q).Object(%q).Update: %v", bucket, attrs.Name, err)
			}
		}
		// Objects with a retention policy must must have the policy removed.
		if attrs.Retention != nil {
			_, err = obj.OverrideUnlockedRetention(true).Update(ctx, storage.ObjectAttrsToUpdate{
				Retention: &storage.ObjectRetention{},
			})
			if err != nil {
				return fmt.Errorf("failed to remove retention from object(%q): %v", attrs.Name, err)
			}
		}

		if err := obj.Generation(attrs.Generation).Delete(ctx); err != nil {
			return fmt.Errorf("Bucket(%q).Object(%q).Delete: %v", bucket, attrs.Name, err)
		}
	}

	// Then delete the bucket itself.
	if err := b.Delete(ctx); err != nil {
		return fmt.Errorf("Bucket.Delete(%q): %v", bucket, err)
	}

	// Waits for a bucket to no longer exist, as it can take time to propagate
	// Errors after 10 successful attempts at retrieving the bucket's attrs
	retries := 10
	delay := 10 * time.Second

	for i := 0; i < retries; i++ {
		if _, err := b.Attrs(ctx); err != nil {
			// Deletion successful.
			return nil
		}
		// Deletion not complete.
		time.Sleep(delay)
	}

	return fmt.Errorf("failed to delete bucket %q", bucket)
}