uqa_storage/key_value/
notification_records.rs

1//
2// Unified Query Algebra
3//
4// Copyright (c) 2023-2026 Cognica, Inc.
5//
6
7//! The bounded notification slot uses ordinary versioned metadata addressing.
8
9use crate::{
10    mvcc::{
11        NotificationRecordLayout, SharedRecordValue, VersionError, VersionResult,
12        NOTIFICATION_PUBLICATION_KEY,
13    },
14    notifications::{NotificationPublication, NotificationPublicationView},
15    read_control::StorageReadControl,
16};
17use uqa_core::memory::BudgetedVec;
18
19pub struct KeyValueNotificationRecords;
20
21impl NotificationRecordLayout for KeyValueNotificationRecords {
22    fn key(&self, control: &StorageReadControl) -> VersionResult<BudgetedVec<u8>> {
23        control.check()?;
24        let mut key = BudgetedVec::new(control.memory());
25        key.push(super::TAG_METADATA)?;
26        key.extend_from_slice(
27            &u32::try_from(NOTIFICATION_PUBLICATION_KEY.len())
28                .map_err(|_| VersionError::InvalidEncoding("notification key is too long"))?
29                .to_be_bytes(),
30        )?;
31        key.extend_from_slice(NOTIFICATION_PUBLICATION_KEY.as_bytes())?;
32        Ok(key)
33    }
34
35    fn encode(
36        &self,
37        publication: &NotificationPublication,
38        control: &StorageReadControl,
39    ) -> VersionResult<SharedRecordValue> {
40        control.check()?;
41        Ok(publication.shared_bytes())
42    }
43
44    fn decode<'a>(
45        &self,
46        key: &[u8],
47        record: &'a [u8],
48        control: &StorageReadControl,
49    ) -> VersionResult<NotificationPublicationView<'a>> {
50        if key != self.key(control)?.as_ref() {
51            return Err(VersionError::InvalidEncoding(
52                "invalid notification metadata key",
53            ));
54        }
55        NotificationPublicationView::decode(record, control)
56    }
57}
uqa_storage/key_value/notification_records.rs

uqa_storage/key_value/
notification_records.rs
