Files
banner/src/web/assets.rs

97 lines
2.7 KiB
Rust

//! Embedded assets for the web frontend
//!
//! This module handles serving static assets that are embedded into the binary
//! at compile time using rust-embed.
use dashmap::DashMap;
use once_cell::sync::Lazy;
use rapidhash::v3::rapidhash_v3;
use rust_embed::RustEmbed;
use std::fmt;
/// Embedded web assets from the dist directory
#[derive(RustEmbed)]
#[folder = "web/dist/"]
#[include = "*"]
#[exclude = "*.map"]
pub struct WebAssets;
/// RapidHash hash type for asset content (u64 native output size)
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct AssetHash(u64);
impl AssetHash {
/// Create a new AssetHash from u64 value
pub fn new(hash: u64) -> Self {
Self(hash)
}
/// Get the hash as a hex string
pub fn to_hex(&self) -> String {
format!("{:016x}", self.0)
}
/// Get the hash as a quoted hex string
pub fn quoted(&self) -> String {
format!("\"{}\"", self.to_hex())
}
}
impl fmt::Display for AssetHash {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.to_hex())
}
}
/// Metadata for an asset including MIME type and RapidHash hash
#[derive(Debug, Clone)]
pub struct AssetMetadata {
pub mime_type: Option<String>,
pub hash: AssetHash,
}
impl AssetMetadata {
/// Check if the etag matches the asset hash
pub fn etag_matches(&self, etag: &str) -> bool {
// Remove quotes if present (ETags are typically quoted)
let etag = etag.trim_matches('"');
// ETags generated from u64 hex should be 16 characters
etag.len() == 16
// Parse the hexadecimal, compare if it matches
&& etag.parse::<u64>()
.map(|parsed| parsed == self.hash.0)
.unwrap_or(false)
}
}
/// Global cache for asset metadata to avoid repeated calculations
static ASSET_CACHE: Lazy<DashMap<String, AssetMetadata>> = Lazy::new(DashMap::new);
/// Get cached asset metadata for a file path, caching on-demand
/// Returns AssetMetadata containing MIME type and RapidHash hash
pub fn get_asset_metadata_cached(path: &str, content: &[u8]) -> AssetMetadata {
// Check cache first
if let Some(cached) = ASSET_CACHE.get(path) {
return cached.value().clone();
}
// Calculate MIME type
let mime_type = mime_guess::from_path(path)
.first()
.map(|mime| mime.to_string());
// Calculate RapidHash hash (using u64 native output size)
let hash_value = rapidhash_v3(content);
let hash = AssetHash::new(hash_value);
let metadata = AssetMetadata { mime_type, hash };
// Only cache if we haven't exceeded the limit
if ASSET_CACHE.len() < 1000 {
ASSET_CACHE.insert(path.to_string(), metadata.clone());
}
metadata
}