97 lines
2.4 KiB
TypeScript
97 lines
2.4 KiB
TypeScript
import { detectFileEncoding } from './file.js'
|
|
import { getFsImplementation } from './fsOperations.js'
|
|
|
|
type CachedFileData = {
|
|
content: string
|
|
encoding: BufferEncoding
|
|
mtime: number
|
|
}
|
|
|
|
/**
|
|
* A simple in-memory cache for file contents with automatic invalidation based on modification time.
|
|
* This eliminates redundant file reads in FileEditTool operations.
|
|
*/
|
|
class FileReadCache {
|
|
private cache = new Map<string, CachedFileData>()
|
|
private readonly maxCacheSize = 1000
|
|
|
|
/**
|
|
* Reads a file with caching. Returns both content and encoding.
|
|
* Cache key includes file path and modification time for automatic invalidation.
|
|
*/
|
|
readFile(filePath: string): { content: string; encoding: BufferEncoding } {
|
|
const fs = getFsImplementation()
|
|
|
|
// Get file stats for cache invalidation
|
|
let stats
|
|
try {
|
|
stats = fs.statSync(filePath)
|
|
} catch (error) {
|
|
// File was deleted, remove from cache and re-throw
|
|
this.cache.delete(filePath)
|
|
throw error
|
|
}
|
|
|
|
const cacheKey = filePath
|
|
const cachedData = this.cache.get(cacheKey)
|
|
|
|
// Check if we have valid cached data
|
|
if (cachedData && cachedData.mtime === stats.mtimeMs) {
|
|
return {
|
|
content: cachedData.content,
|
|
encoding: cachedData.encoding,
|
|
}
|
|
}
|
|
|
|
// Cache miss or stale data - read the file
|
|
const encoding = detectFileEncoding(filePath)
|
|
const content = fs
|
|
.readFileSync(filePath, { encoding })
|
|
.replaceAll('\r\n', '\n')
|
|
|
|
// Update cache
|
|
this.cache.set(cacheKey, {
|
|
content,
|
|
encoding,
|
|
mtime: stats.mtimeMs,
|
|
})
|
|
|
|
// Evict oldest entries if cache is too large
|
|
if (this.cache.size > this.maxCacheSize) {
|
|
const firstKey = this.cache.keys().next().value
|
|
if (firstKey) {
|
|
this.cache.delete(firstKey)
|
|
}
|
|
}
|
|
|
|
return { content, encoding }
|
|
}
|
|
|
|
/**
|
|
* Clears the entire cache. Useful for testing or memory management.
|
|
*/
|
|
clear(): void {
|
|
this.cache.clear()
|
|
}
|
|
|
|
/**
|
|
* Removes a specific file from the cache.
|
|
*/
|
|
invalidate(filePath: string): void {
|
|
this.cache.delete(filePath)
|
|
}
|
|
|
|
/**
|
|
* Gets cache statistics for debugging/monitoring.
|
|
*/
|
|
getStats(): { size: number; entries: string[] } {
|
|
return {
|
|
size: this.cache.size,
|
|
entries: Array.from(this.cache.keys()),
|
|
}
|
|
}
|
|
}
|
|
|
|
// Export a singleton instance
|
|
export const fileReadCache = new FileReadCache()
|