Edison Jwa
40883c40c8
Add per-crate variant_ctx() helper methods to StorageError, BlobCacheError, ProtocolError, and BridgeError. Replace 78 .map_err(|e| format!(...)) closures with concise context calls. Identical error messages preserved.
chanora_cache
Disposable content-addressed blob cache for avatar and icon files. Wraps cacache for crash safety and integrity verification. Separated from chanora_storage because cache owns reconstructible, disposable blob data with different durability and backup semantics.
Architecture
BlobCache— async blob store backed by cacache's content-v2 / index-v2 on-disk layout.- Keys are protocol identifiers prefixed by type:
av_<32-char-hex>for avatars (MD5),ic_<decimal>for icons (CRC32). - Cacache handles dedup and SSRI integrity verification on every read.
- Corrupt entries are automatically removed on read failure.
- LRU eviction by timestamp when total size exceeds the configured cap.
Public API Summary
Types
| Type | Role |
|---|---|
BlobCache |
Content-addressed blob cache |
BlobCacheError |
Io, InvalidKey |
Key methods on BlobCache
new(cache_dir, max_bytes)— create or open the cache.max_bytes = 0disables eviction.put(prefix, key, data)— store a blob (async)get(prefix, key)→Option<Vec<u8>>— read a blob, with integrity check (async)remove(prefix, key)— delete a specific blob (async)clear()— delete all blobs (async)total_size()→u64— sum of all blob sizes (async)evict()— remove oldest entries until undermax_bytescap (async)
Constants
PREFIX_AVATAR="av_"— avatar key prefixPREFIX_ICON="ic_"— icon key prefix
Key validation
Avatar keys must be exactly 32 hex characters. Icon keys must be non-empty decimal digits. Unknown prefixes are rejected. This prevents malformed entries from polluting the cache.