reth_storage_api/
metadata.rs

1//! Metadata provider trait for reading and writing node metadata.
2
3use alloc::vec::Vec;
4use reth_db_api::models::StorageSettings;
5use reth_storage_errors::provider::{ProviderError, ProviderResult};
6
7/// Metadata keys.
8pub mod keys {
9    /// Storage configuration settings for this node.
10    pub const STORAGE_SETTINGS: &str = "storage_settings";
11}
12
13/// Client trait for reading node metadata from the database.
14#[auto_impl::auto_impl(&)]
15pub trait MetadataProvider: Send {
16    /// Get a metadata value by key
17    fn get_metadata(&self, key: &str) -> ProviderResult<Option<Vec<u8>>>;
18
19    /// Get storage settings for this node.
20    ///
21    /// If the stored metadata can't be deserialized (e.g. the format changed),
22    /// this returns `None` instead of an error so commands like `db clear` can
23    /// still operate without requiring a compatible metadata schema.
24    fn storage_settings(&self) -> ProviderResult<Option<StorageSettings>> {
25        Ok(self
26            .get_metadata(keys::STORAGE_SETTINGS)?
27            .and_then(|bytes| serde_json::from_slice(&bytes).ok()))
28    }
29}
30
31/// Client trait for writing node metadata to the database.
32pub trait MetadataWriter: Send {
33    /// Write a metadata value
34    fn write_metadata(&self, key: &str, value: Vec<u8>) -> ProviderResult<()>;
35
36    /// Write storage settings for this node
37    ///
38    /// Be sure to update provider factory cache with
39    /// [`StorageSettingsCache::set_storage_settings_cache`].
40    fn write_storage_settings(&self, settings: StorageSettings) -> ProviderResult<()> {
41        self.write_metadata(
42            keys::STORAGE_SETTINGS,
43            serde_json::to_vec(&settings).map_err(ProviderError::other)?,
44        )
45    }
46}
47
48/// Trait for caching storage settings on a provider factory.
49pub trait StorageSettingsCache: Send {
50    /// Gets the cached storage settings.
51    fn cached_storage_settings(&self) -> StorageSettings;
52
53    /// Sets the storage settings of this `ProviderFactory`.
54    ///
55    /// IMPORTANT: It does not save settings in storage, that should be done by
56    /// [`MetadataWriter::write_storage_settings`]
57    fn set_storage_settings_cache(&self, settings: StorageSettings);
58}
reth_storage_api/metadata.rs

reth_storage_api/
metadata.rs
