ic_memory/
schema.rs

1use serde::{Deserialize, Serialize};
2
3///
4/// SchemaMetadata
5///
6/// Optional diagnostic metadata for an in-place store schema.
7///
8/// This metadata helps humans and frameworks diagnose which schema version was
9/// declared in each generation. It is bounded and validated for durable ledger
10/// encoding, but it does not perform application schema migrations or validate
11/// stable data semantics.
12///
13
14#[derive(Clone, Debug, Default, Deserialize, Eq, PartialEq, Serialize)]
15#[serde(deny_unknown_fields)]
16pub struct SchemaMetadata {
17    /// Optional in-place schema version.
18    pub schema_version: Option<u32>,
19}
20
21impl SchemaMetadata {
22    /// Construct schema metadata after validating the persisted encoding bounds.
23    pub fn new(schema_version: Option<u32>) -> Result<Self, SchemaMetadataError> {
24        let metadata = Self { schema_version };
25        metadata.validate()?;
26        Ok(metadata)
27    }
28
29    /// Validate schema metadata encoding rules.
30    pub fn validate(&self) -> Result<(), SchemaMetadataError> {
31        if self.schema_version == Some(0) {
32            return Err(SchemaMetadataError::InvalidVersion);
33        }
34        Ok(())
35    }
36}
37
38///
39/// SchemaMetadataError
40///
41/// Schema metadata validation failure.
42///
43
44#[derive(Clone, Debug, Eq, thiserror::Error, PartialEq)]
45pub enum SchemaMetadataError {
46    /// Schema version zero is reserved for absence.
47    #[error("schema_version must be greater than zero when present")]
48    InvalidVersion,
49}
ic_memory/schema.rs

ic_memory/
schema.rs
