s1d3sw1ped
b7e3a0da86
Release Tag / release (push) Successful in 34s
- Added metrics for bytes saved from cache to improve performance insights. - Updated cache eviction strategies in MemoryFS and DiskFS to include metrics tracking for hits and evictions. - Enhanced README.md with updated garbage collection algorithm descriptions and recommendations for cache usage. - Introduced new madviseSequential functionality for improved memory access hints on Unix systems. - Adjusted validation configuration in examples to better reflect realistic usage scenarios.
703 lines
25 KiB
Go
703 lines
25 KiB
Go
// steamcache/handler.go
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// HTTP handler surface: ServeHTTP (thin dispatcher), special endpoint handling,
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// Options/NewWithOptions. Phase 3: requestProcessor + 4 narrow interfaces + injection
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// introduced as foundation (bulk logic preserved on SteamCache pending future small PR
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// per plan Risks; see deferral block below). Text metrics writer promoted.
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package steamcache
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import (
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"bytes"
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"fmt"
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"io"
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"net/http"
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"net/url"
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"strings"
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"time"
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"s1d3sw1ped/steamcache2/steamcache/logger"
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"s1d3sw1ped/steamcache2/steamcache/metrics"
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)
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// Minimal Options + NewWithOptions usage (delegates to the main positional constructor).
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// NewWithOptions propagates the error return from New (see New godoc).
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type Options struct {
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Address string
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MemorySize string
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DiskSize string
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DiskPath string
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Upstream string
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MemoryGC string
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DiskGC string
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MaxConcurrentRequests int64
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MaxRequestsPerClient int64
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// New config fields for hardening (max object size + trusted proxies)
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MaxObjectSize string
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TrustedProxies []string
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}
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func NewWithOptions(o Options) (*SteamCache, error) {
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return New(o.Address, o.MemorySize, o.DiskSize, o.DiskPath, o.Upstream, o.MemoryGC, o.DiskGC, o.MaxConcurrentRequests, o.MaxRequestsPerClient, o.MaxObjectSize, o.TrustedProxies)
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}
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// handleSpecialEndpoints handles non-content paths (health, heartbeat, metrics) and
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// returns true if the request was fully handled (caller should return immediately).
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// Non-GET method check remains in ServeHTTP for clarity.
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func (sc *SteamCache) handleSpecialEndpoints(w http.ResponseWriter, r *http.Request, clientIP string) bool {
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if r.URL.Path == "/" {
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logger.Logger.Debug().
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Str("client_ip", clientIP).
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Msg("Health check request")
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w.WriteHeader(http.StatusOK) // this is used by steamcache2's upstream verification at startup
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return true
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}
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if r.URL.String() == "/lancache-heartbeat" {
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logger.Logger.Debug().
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Str("client_ip", clientIP).
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Msg("LanCache heartbeat request")
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w.Header().Add("X-LanCache-Processed-By", "SteamCache2")
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w.WriteHeader(http.StatusNoContent)
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_, _ = w.Write(nil) // client write error ignored (heartbeat path; nil write is no-op)
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return true
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}
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if r.URL.String() == "/metrics" {
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// Return metrics in a simple text format
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stats := sc.GetMetrics()
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w.Header().Set("Content-Type", "text/plain")
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w.WriteHeader(http.StatusOK)
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metrics.WriteText(w, stats)
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return true
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}
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// Not a special path — signal caller to continue with service detection / normal flow.
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// Unsupported services will hit the final 404 in ServeHTTP.
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return false
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}
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// handleCacheHit attempts to serve the request from the VFS cache (memory or disk tier).
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// It handles deserialization, corruption cleanup, metrics, and streaming on success.
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// Returns true if the request was fully handled (ServeHTTP caller should return immediately).
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func (sc *SteamCache) handleCacheHit(w http.ResponseWriter, r *http.Request, cachePath, cacheKey, urlPath string, service *ServiceConfig, clientIP string, tstart time.Time) bool {
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// Try to serve from cache
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file, err := sc.vfs.Open(cachePath)
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if err == nil {
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defer func() { _ = file.Close() }() // best-effort close of cache file reader; error secondary (data already read or connection issue)
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// Read the entire cached file
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cachedData, err := io.ReadAll(file)
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if err != nil {
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logger.Logger.Warn().
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Str("key", cacheKey).
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Str("url", urlPath).
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Err(err).
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Msg("Failed to read cached file - removing corrupted entry")
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_ = sc.vfs.Delete(cachePath) // best-effort cleanup of corrupt entry; failure non-fatal (logged)
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} else {
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// Deserialize using new format
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cacheFile, err := deserializeCacheFile(cachedData)
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if err != nil {
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// Cache file is corrupted or invalid format
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logger.Logger.Warn().
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Str("key", cacheKey).
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Str("url", urlPath).
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Err(err).
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Msg("Failed to deserialize cache file - removing corrupted entry")
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_ = sc.vfs.Delete(cachePath) // best-effort cleanup of corrupt entry; failure non-fatal (logged)
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} else {
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// Track cache hit metrics
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sc.metrics.IncrementCacheHits()
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sc.metrics.AddResponseTime(time.Since(tstart))
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sc.metrics.AddBytesServed(int64(len(cachedData)))
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sc.metrics.AddBytesSaved(int64(len(cachedData)))
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sc.metrics.IncrementServiceRequests(service.Name)
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logger.Logger.Debug().
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Str("key", cacheKey).
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Str("url", urlPath).
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Str("content_hash", cacheFile.ContentHash).
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Msg("Successfully loaded from cache")
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// Stream the raw HTTP response directly
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sc.streamCachedResponse(w, r, cacheFile, cacheKey, clientIP, tstart)
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return true
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}
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}
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// If we reach here, cache validation failed and we need to fetch from upstream
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}
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return false
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}
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// waitForCoalesced handles the follower path for a coalesced in-flight request.
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// It waits on the broadcast doneCh, serves the buffered response (or error), updates
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// coalesced metrics, and returns (the caller in ServeHTTP does the outer return).
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func (sc *SteamCache) waitForCoalesced(w http.ResponseWriter, r *http.Request, coalescedReq *coalescedRequest, cacheKey, urlPath string, service *ServiceConfig, clientIP string, tstart time.Time) {
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// Wait for the existing download to complete
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logger.Logger.Debug().
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Str("key", cacheKey).
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Str("url", urlPath).
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Str("client_ip", clientIP).
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Int("waiting_clients", int(coalescedReq.waitingCount.Load())).
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Msg("Joining coalesced request")
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// Wait on the broadcast doneCh (closed once by leader). All N waiters wake.
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select {
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case <-coalescedReq.doneCh:
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case <-r.Context().Done():
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return
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}
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coalescedReq.mu.Lock()
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if coalescedReq.completionErr != nil {
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err := coalescedReq.completionErr
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coalescedReq.mu.Unlock()
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logger.Logger.Error().
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Err(err).
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Str("key", cacheKey).
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Str("url", urlPath).
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Str("client_ip", clientIP).
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Msg("Coalesced request failed")
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sc.metrics.IncrementErrors()
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http.Error(w, "Upstream request failed", http.StatusInternalServerError)
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return
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}
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if coalescedReq.responseData == nil {
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coalescedReq.mu.Unlock()
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logger.Logger.Error().
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Str("key", cacheKey).
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Str("url", urlPath).
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Str("client_ip", clientIP).
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Msg("No response data available for coalesced client")
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sc.metrics.IncrementErrors()
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http.Error(w, "No response data available", http.StatusInternalServerError)
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return
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}
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// Copy the buffered response data + headers under lock (consistent with complete() write side; safe for happens-before + future changes)
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responseData := make([]byte, len(coalescedReq.responseData))
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copy(responseData, coalescedReq.responseData)
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headersCopy := make(http.Header, len(coalescedReq.responseHeaders))
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for k, vv := range coalescedReq.responseHeaders {
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headersCopy[k] = append([]string(nil), vv...)
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}
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coalescedReq.mu.Unlock()
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// Serve the buffered response
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for k, vv := range headersCopy {
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for _, v := range vv {
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w.Header().Add(k, v)
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}
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}
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w.Header().Set("X-LanCache-Status", "HIT-COALESCED")
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w.Header().Set("X-LanCache-Processed-By", "SteamCache2")
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w.WriteHeader(coalescedReq.statusCode)
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_, _ = w.Write(responseData) // client write error ignored (disconnect during coalesced response send is not actionable)
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// Track coalesced cache hit metrics
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sc.metrics.IncrementCacheCoalesced()
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sc.metrics.AddResponseTime(time.Since(tstart))
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sc.metrics.AddBytesServed(int64(len(responseData)))
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sc.metrics.AddBytesSaved(int64(len(responseData)))
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sc.metrics.IncrementServiceRequests(service.Name)
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logger.Logger.Info().
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Str("cache_key", cacheKey).
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Str("url", urlPath).
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Str("host", r.Host).
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Str("client_ip", clientIP).
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Str("cache_status", "HIT-COALESCED").
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Int("waiting_clients", int(coalescedReq.waitingCount.Load())).
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Int64("file_size", int64(len(responseData))).
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Dur("response_time", time.Since(tstart)).
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Msg("cache request")
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}
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func (sc *SteamCache) ServeHTTP(w http.ResponseWriter, r *http.Request) {
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clientIP := getClientIP(r, sc.trustedProxies)
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// Set keep-alive headers for better performance
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w.Header().Set("Connection", "keep-alive")
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w.Header().Set("Keep-Alive", "timeout=300, max=1000")
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// Apply global concurrency limit first
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// Propagate request context for cancellation support
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if err := sc.requestSemaphore.Acquire(r.Context(), 1); err != nil {
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// Capacity rejections are counted in Errors + RateLimited but intentionally *before* TotalRequests.
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// This preserves original hit-rate / processed-traffic semantics for accepted requests only.
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// (All other 5xx occur after Total inc.)
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sc.metrics.IncrementRateLimited()
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sc.metrics.IncrementErrors()
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sc.metrics.IncrementServiceError("rate_limit")
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logger.Logger.Warn().Str("client_ip", clientIP).Msg("Server at capacity, rejecting request")
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http.Error(w, "Server busy, please try again later", http.StatusServiceUnavailable)
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return
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}
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defer sc.requestSemaphore.Release(1)
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// Apply per-client rate limiting
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clientLimiter := sc.getOrCreateClientLimiter(clientIP)
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// Per-client request limiting (context aware)
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if err := clientLimiter.semaphore.Acquire(r.Context(), 1); err != nil {
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logger.Logger.Warn().
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Str("client_ip", clientIP).
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Int("max_per_client", int(sc.maxRequestsPerClient)).
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Msg("Client exceeded concurrent request limit")
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http.Error(w, "Too many concurrent requests from this client", http.StatusTooManyRequests)
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return
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}
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defer clientLimiter.semaphore.Release(1)
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if r.Method != http.MethodGet {
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logger.Logger.Warn().
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Str("method", r.Method).
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Str("client_ip", clientIP).
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Msg("Only GET method is supported")
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http.Error(w, "Only GET method is supported", http.StatusMethodNotAllowed)
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return
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}
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if sc.handleSpecialEndpoints(w, r, clientIP) {
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return
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}
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// Check if this is a request from a supported service
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if service, isSupported := sc.detectService(r); isSupported {
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// trim the query parameters from the URL path
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// this is necessary because the cache key should not include query parameters
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urlPath := strings.SplitN(r.URL.String(), "?", 2)[0] // trim query for cache key (SplitN makes intent explicit vs Cut + ignored bool)
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// Validate URL path for security
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if err := validateURLPath(urlPath); err != nil {
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logger.Logger.Warn().
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Err(err).
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Str("url", urlPath).
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Str("client_ip", clientIP).
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Msg("Invalid URL path detected")
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http.Error(w, "Invalid URL", http.StatusBadRequest)
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return
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}
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tstart := time.Now()
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// Generate service cache key: {service}/{hash} (prefix indicates service via User-Agent)
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cacheKey, err := generateServiceCacheKey(urlPath, service.Prefix)
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if err != nil {
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logger.Logger.Warn().
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Err(err).
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Str("url", urlPath).
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Str("service", service.Name).
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Str("client_ip", clientIP).
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Msg("Failed to generate cache key")
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http.Error(w, "Invalid URL", http.StatusBadRequest)
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return
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}
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w.Header().Add("X-LanCache-Processed-By", "SteamCache2") // SteamPrefill uses this header to determine if the request was processed by the cache maybe steam uses it too
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cachePath := cacheKey // You may want to add a .http or .cache extension for clarity
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logger.Logger.Debug().
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Str("url", urlPath).
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Str("key", cacheKey).
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Str("client_ip", clientIP).
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Msg("Generated cache key")
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// Only count real cacheable service traffic toward total_requests / hit_rate.
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// Special endpoints (/, /metrics, /lancache-heartbeat) and unsupported services
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// are intentionally excluded so that idle monitoring doesn't dilute the hit rate.
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sc.metrics.IncrementTotalRequests()
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if sc.handleCacheHit(w, r, cachePath, cacheKey, urlPath, service, clientIP, tstart) {
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return
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}
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// If we reach here, cache validation failed and we need to fetch from upstream
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// Check for coalesced request (another client already downloading this)
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coalescedReq, isNew := sc.getOrCreateCoalescedRequest(cacheKey)
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if !isNew {
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sc.waitForCoalesced(w, r, coalescedReq, cacheKey, urlPath, service, clientIP, tstart)
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return
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}
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// Remove coalesced request when done
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defer sc.removeCoalescedRequest(cacheKey)
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var req *http.Request
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if sc.upstream != "" { // if an upstream server is configured, proxy the request to the upstream server
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ur, joinErr := url.JoinPath(sc.upstream, urlPath)
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if joinErr != nil {
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logger.Logger.Error().Err(joinErr).Str("upstream", sc.upstream).Msg("Failed to join URL path")
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sc.metrics.IncrementErrors()
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http.Error(w, "Failed to join URL path", http.StatusInternalServerError)
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return
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}
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var createErr error
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req, createErr = http.NewRequestWithContext(r.Context(), http.MethodGet, ur, nil)
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if createErr != nil {
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logger.Logger.Error().Err(createErr).Str("upstream", sc.upstream).Msg("Failed to create request")
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sc.metrics.IncrementErrors()
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http.Error(w, "Failed to create request", http.StatusInternalServerError)
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return
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}
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req.Host = r.Host
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} else { // if no upstream server is configured, proxy the request to the host specified in the request
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host := r.Host
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if r.Header.Get("X-Sls-Https") == "enable" {
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host = "https://" + host
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} else {
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host = "http://" + host
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}
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ur, joinErr := url.JoinPath(host, urlPath)
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if joinErr != nil {
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logger.Logger.Error().Err(joinErr).Str("host", host).Msg("Failed to join URL path")
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sc.metrics.IncrementErrors()
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http.Error(w, "Failed to join URL path", http.StatusInternalServerError)
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return
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}
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var createErr error
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req, createErr = http.NewRequestWithContext(r.Context(), http.MethodGet, ur, nil)
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if createErr != nil {
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logger.Logger.Error().Err(createErr).Str("host", host).Msg("Failed to create request")
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sc.metrics.IncrementErrors()
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http.Error(w, "Failed to create request", http.StatusInternalServerError)
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return
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}
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req.Host = r.Host
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}
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// Copy headers from the original request to the new request
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// BUT exclude Range headers - we always want to cache the full file
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for key, values := range r.Header {
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// Skip Range headers to ensure we always cache the complete file
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if strings.ToLower(key) == "range" {
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logger.Logger.Debug().
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Str("key", cacheKey).
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Str("url", urlPath).
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Str("range_header", values[0]).
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Msg("Skipping Range header to cache full file")
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continue
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}
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for _, value := range values {
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req.Header.Add(key, value)
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}
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}
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// Retry logic
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backoffSchedule := []time.Duration{1 * time.Second, 3 * time.Second, 10 * time.Second}
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var resp *http.Response
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for i, backoff := range backoffSchedule {
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resp, err = sc.client.Do(req)
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if err == nil && resp.StatusCode == http.StatusOK {
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break
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}
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if i < len(backoffSchedule)-1 {
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time.Sleep(backoff)
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}
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}
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if err != nil {
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logger.Logger.Error().Err(err).Str("url", req.URL.String()).Msg("Failed to fetch the requested URL")
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if resp != nil {
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_ = resp.Body.Close() // best-effort close on upstream fetch error; primary error logged/returned
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}
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// Complete coalesced request with error
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if isNew {
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coalescedReq.complete(nil, err)
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}
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sc.metrics.IncrementErrors()
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sc.metrics.IncrementUpstreamErrors()
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sc.metrics.IncrementServiceError("upstream")
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http.Error(w, "Failed to fetch the requested URL", http.StatusInternalServerError)
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return
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}
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if resp.StatusCode != http.StatusOK {
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logger.Logger.Error().Int("status_code", resp.StatusCode).Str("url", req.URL.String()).Msg("Failed to fetch the requested URL (non-OK status after retries)")
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_ = resp.Body.Close() // best-effort close on non-OK upstream; primary error path
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// Complete coalesced request with error
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if isNew {
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coalescedReq.complete(nil, fmt.Errorf("upstream returned status %d", resp.StatusCode))
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}
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sc.metrics.IncrementErrors()
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sc.metrics.IncrementUpstreamErrors()
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sc.metrics.IncrementServiceError("upstream")
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http.Error(w, "Failed to fetch the requested URL", http.StatusInternalServerError)
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return
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}
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defer func() { _ = resp.Body.Close() }() // best-effort close for success upstream response body (standard handler cleanup)
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// Fast path: Flexible lightweight validation for all files
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// Multiple validation layers ensure data integrity without blocking legitimate Steam content
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// Method 2: Content-Type Validation (Steam files can be various types)
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contentType := resp.Header.Get("Content-Type")
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if contentType != "" {
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// Log the content type for monitoring, but don't restrict based on it
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// Steam serves different content types: chunks, manifests, patches, etc.
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logger.Logger.Debug().
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Str("url", req.URL.String()).
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Str("content_type", contentType).
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Str("service", service.Name).
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Msg("Content type from upstream")
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}
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// Method 3: Content-Length Validation
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expectedSize := resp.ContentLength
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// Reject only truly invalid content lengths (zero or negative)
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// When max object size limit is set, treat unknown or lying Content-Length as potential oversize (return 413).
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if expectedSize <= 0 {
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if sc.maxObjectSize > 0 {
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logger.Logger.Warn().
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Str("url", req.URL.String()).
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Int64("content_length", expectedSize).
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Int64("max_object_size", sc.maxObjectSize).
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Msg("Chunked/unknown Content-Length with size limit set - treating as potential oversize")
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if isNew {
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coalescedReq.complete(nil, fmt.Errorf("chunked response with size limit"))
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}
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sc.metrics.IncrementErrors()
|
|
http.Error(w, "Response too large (chunked)", http.StatusRequestEntityTooLarge)
|
|
return
|
|
}
|
|
logger.Logger.Error().
|
|
Str("url", req.URL.String()).
|
|
Int64("content_length", expectedSize).
|
|
Msg("Invalid content length, rejecting file")
|
|
sc.metrics.IncrementErrors()
|
|
http.Error(w, "Invalid content length", http.StatusBadGateway)
|
|
return
|
|
}
|
|
|
|
// Content length is valid - no size restrictions to keep logs clean
|
|
|
|
// Bounded response size to prevent OOM (capped reader chosen for minimal VFS impact).
|
|
// Large objects still served if <= limit; >limit returns 413 without caching or unbounded ReadAll.
|
|
// Coalesced paths also protected (leader enforces before buffering).
|
|
// Security: mitigates DoS via huge malicious upstream responses/manifests.
|
|
if sc.maxObjectSize > 0 && expectedSize > sc.maxObjectSize {
|
|
logger.Logger.Warn().
|
|
Str("url", req.URL.String()).
|
|
Int64("content_length", expectedSize).
|
|
Int64("max_object_size", sc.maxObjectSize).
|
|
Msg("Response exceeds configured max object size limit - rejecting to prevent OOM")
|
|
if isNew {
|
|
coalescedReq.complete(nil, fmt.Errorf("response too large: %d > %d", expectedSize, sc.maxObjectSize))
|
|
}
|
|
sc.metrics.IncrementErrors()
|
|
http.Error(w, "Response too large", http.StatusRequestEntityTooLarge)
|
|
return
|
|
}
|
|
|
|
// Read the entire response body into memory to avoid consuming it twice
|
|
// LimitReader caps the body even if the client lied about Content-Length.
|
|
readLimit := resp.ContentLength
|
|
if sc.maxObjectSize > 0 && (readLimit <= 0 || readLimit > sc.maxObjectSize) {
|
|
readLimit = sc.maxObjectSize
|
|
}
|
|
bodyData, err := io.ReadAll(io.LimitReader(resp.Body, readLimit+1))
|
|
if err != nil {
|
|
logger.Logger.Error().
|
|
Err(err).
|
|
Str("url", req.URL.String()).
|
|
Msg("Failed to read response body")
|
|
sc.metrics.IncrementErrors()
|
|
http.Error(w, "Failed to read response", http.StatusInternalServerError)
|
|
return
|
|
}
|
|
// Detect truncation from LimitReader (lying CL or chunked > limit)
|
|
if sc.maxObjectSize > 0 && int64(len(bodyData)) > sc.maxObjectSize {
|
|
if isNew {
|
|
coalescedReq.complete(nil, fmt.Errorf("response body exceeded limit"))
|
|
}
|
|
sc.metrics.IncrementErrors()
|
|
http.Error(w, "Response too large", http.StatusRequestEntityTooLarge)
|
|
return
|
|
}
|
|
// Body closed by defer resp.Body.Close() at entry to success path
|
|
|
|
// Reconstruct the exact HTTP response as received from upstream
|
|
rawResponse := sc.reconstructRawResponse(resp, bodyData)
|
|
|
|
// Write to response
|
|
// Remove hop-by-hop headers (server-specific like Server are included in hopByHop set)
|
|
for k, vv := range filterHopByHopHeaders(resp.Header) {
|
|
for _, v := range vv {
|
|
w.Header().Add(k, v)
|
|
}
|
|
}
|
|
// Add our own headers
|
|
w.Header().Set("X-LanCache-Status", "MISS")
|
|
w.Header().Set("X-LanCache-Processed-By", "SteamCache2")
|
|
|
|
// Stream the response body to client
|
|
w.WriteHeader(resp.StatusCode)
|
|
_, _ = w.Write(bodyData) // client write error ignored (disconnect during MISS body send is not actionable)
|
|
|
|
// Track cache miss metrics
|
|
sc.metrics.IncrementCacheMisses()
|
|
sc.metrics.AddResponseTime(time.Since(tstart))
|
|
sc.metrics.AddBytesServed(int64(len(bodyData)))
|
|
sc.metrics.IncrementServiceRequests(service.Name)
|
|
|
|
// Verify we received the complete file by checking Content-Length
|
|
if !sc.verifyCompleteFile(bodyData, resp, urlPath, cacheKey) {
|
|
logger.Logger.Warn().
|
|
Str("key", cacheKey).
|
|
Str("url", urlPath).
|
|
Int("received_bytes", len(bodyData)).
|
|
Int64("expected_bytes", resp.ContentLength).
|
|
Msg("Incomplete file received - not caching to allow retry")
|
|
if isNew {
|
|
coalescedReq.complete(nil, fmt.Errorf("incomplete file received - not caching"))
|
|
}
|
|
return
|
|
}
|
|
|
|
// Serialize the raw response using our new cache format
|
|
cacheData, err := serializeRawResponse(rawResponse)
|
|
if err != nil {
|
|
logger.Logger.Warn().
|
|
Str("key", cacheKey).
|
|
Str("url", urlPath).
|
|
Err(err).
|
|
Msg("Failed to serialize cache file")
|
|
sc.metrics.IncrementCacheWriteFailures()
|
|
sc.metrics.IncrementServiceError("serialize")
|
|
} else {
|
|
// Store the serialized cache data
|
|
cacheWriter, err := sc.vfs.Create(cachePath, int64(len(cacheData)))
|
|
if err == nil {
|
|
defer func() { _ = cacheWriter.Close() }() // best-effort close of cache writer; errors on close (e.g. final sync) logged via prior write checks or non-fatal
|
|
|
|
// Write the serialized cache data
|
|
bytesWritten, cacheErr := cacheWriter.Write(cacheData)
|
|
|
|
if cacheErr != nil || bytesWritten != len(cacheData) {
|
|
logger.Logger.Warn().
|
|
Str("key", cacheKey).
|
|
Str("url", urlPath).
|
|
Int("expected", len(cacheData)).
|
|
Int("written", bytesWritten).
|
|
Err(cacheErr).
|
|
Msg("Cache write failed or incomplete - removing corrupted entry")
|
|
sc.metrics.IncrementCacheWriteFailures()
|
|
sc.metrics.IncrementServiceError("cache_write")
|
|
_ = sc.vfs.Delete(cachePath) // best-effort removal of partial corrupt cache entry on write failure; non-fatal. Deferred cacheWriter.Close() (from earlier in block) runs after this on error unwind path (harmless per DiskFS design)
|
|
} else {
|
|
logger.Logger.Debug().
|
|
Str("key", cacheKey).
|
|
Str("url", urlPath).
|
|
Str("service", service.Name).
|
|
Int("size", bytesWritten).
|
|
Msg("Successfully cached response")
|
|
}
|
|
} else {
|
|
logger.Logger.Warn().
|
|
Str("key", cacheKey).
|
|
Str("url", urlPath).
|
|
Err(err).
|
|
Msg("Failed to create cache file")
|
|
sc.metrics.IncrementCacheWriteFailures()
|
|
sc.metrics.IncrementServiceError("cache_create")
|
|
}
|
|
}
|
|
|
|
// Complete coalesced request with the original response
|
|
if isNew {
|
|
coalescedResp := &http.Response{
|
|
StatusCode: resp.StatusCode,
|
|
Status: resp.Status,
|
|
Header: make(http.Header),
|
|
Body: io.NopCloser(bytes.NewReader(bodyData)), // Buffered body for coalesced clients
|
|
}
|
|
for k, vv := range resp.Header {
|
|
coalescedResp.Header[k] = vv
|
|
}
|
|
coalescedReq.setResponseData(bodyData)
|
|
coalescedReq.complete(coalescedResp, nil)
|
|
}
|
|
|
|
logger.Logger.Info().
|
|
Str("cache_key", cacheKey).
|
|
Str("url", urlPath).
|
|
Str("host", r.Host).
|
|
Str("client_ip", clientIP).
|
|
Str("service", service.Name).
|
|
Str("cache_status", "MISS").
|
|
Int64("file_size", int64(len(bodyData))).
|
|
Dur("response_time", time.Since(tstart)).
|
|
Msg("cache request")
|
|
|
|
return
|
|
}
|
|
|
|
http.Error(w, "Not found", http.StatusNotFound)
|
|
}
|
|
|
|
// Phase 3 foundation (requestProcessor + narrow interfaces for DI/fakes) introduced here.
|
|
// Full bulk move + active delegation deferred (intentionally) to keep diff minimal
|
|
// and protect shutdown/concurrency hygiene per plan explicit Risks note + "small PRs".
|
|
// Wiring + types enable the goal; existing logic + helpers preserved verbatim.
|
|
type cacheReader interface {
|
|
Open(key string) (io.ReadCloser, error)
|
|
Create(key string, size int64) (io.WriteCloser, error)
|
|
Delete(key string) error
|
|
}
|
|
|
|
type upstreamFetcher interface {
|
|
Do(req *http.Request) (*http.Response, error)
|
|
}
|
|
|
|
// requestCoalescer / requestRateLimiter: renamed from bare plan suggestion ("coalescer"/"rateLimiter")
|
|
// to avoid redeclaration with existing unexported concrete types in same package. Concretes
|
|
// satisfy via identical methods (duck typing); intent for narrow DI/fakes preserved exactly.
|
|
type requestCoalescer interface {
|
|
getOrCreate(cacheKey string) (*coalescedRequest, bool)
|
|
remove(cacheKey string)
|
|
}
|
|
|
|
type requestRateLimiter interface {
|
|
getOrCreate(clientIP string) *clientLimiter
|
|
}
|
|
|
|
type requestProcessor struct {
|
|
cache cacheReader
|
|
fetcher upstreamFetcher
|
|
coal requestCoalescer
|
|
rate requestRateLimiter
|
|
metrics *metrics.Metrics
|
|
serviceMgr *ServiceManager
|
|
scForFormat *SteamCache
|
|
maxObjectSize int64
|
|
upstream string
|
|
trustedProxies []string
|
|
}
|
|
|
|
func newRequestProcessor(sc *SteamCache) *requestProcessor {
|
|
return &requestProcessor{
|
|
cache: sc.vfs,
|
|
fetcher: sc.client,
|
|
coal: sc.coalescer,
|
|
rate: sc.clientRateLimiter,
|
|
metrics: sc.metrics,
|
|
serviceMgr: sc.serviceManager,
|
|
scForFormat: sc,
|
|
maxObjectSize: sc.maxObjectSize,
|
|
upstream: sc.upstream,
|
|
trustedProxies: sc.trustedProxies,
|
|
}
|
|
}
|
|
|
|
// (serve hook prepared for bulk logic move; omitted in this step to avoid
|
|
// unused-method lint while keeping zero behavior change and full test coverage.
|
|
// The requestProcessor type + interfaces + New wiring fulfill the introduce/ctor
|
|
// injection goals of Phase 3 with minimal risk.)
|