feat: implement chunked upload handler and update config validation for session timeout

cmd/server/chunked_upload_handler.go

@@ -3,6 +3,7 @@
 package main
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -32,8 +33,6 @@ func handleChunkedUpload(w http.ResponseWriter, r *http.Request) {
 	// Extract headers for chunked upload
 	sessionID := r.Header.Get("X-Upload-Session-ID")
 	chunkNumberStr := r.Header.Get("X-Chunk-Number")
-	totalChunksStr := r.Header.Get("X-Total-Chunks")
-	contentRange := r.Header.Get("Content-Range")
 	filename := r.Header.Get("X-Filename")
 
 	// Handle session creation for new uploads

cmd/server/config_validator.go

@@ -301,10 +301,10 @@ func validateUploadsConfig(uploads *UploadsConfig, result *ConfigValidationResul
 		}
 	}
 
-	// Validate resumable age
-	if uploads.MaxResumableAge != "" {
-		if _, err := time.ParseDuration(uploads.MaxResumableAge); err != nil {
-			result.AddError("uploads.max_resumable_age", uploads.MaxResumableAge, "invalid resumable age format")
+	// Validate session timeout (renamed from max_resumable_age)
+	if uploads.SessionTimeout != "" {
+		if _, err := time.ParseDuration(uploads.SessionTimeout); err != nil {
+			result.AddError("uploads.session_timeout", uploads.SessionTimeout, "invalid session timeout format")
 		}
 	}
 }

cmd/server/network_resilience.go

@@ -251,7 +251,7 @@ func RetryableUploadWrapper(originalHandler http.HandlerFunc, maxRetries int) ht
 			if attempt > 0 {
 				// Exponential backoff with jitter
 				delay := time.Duration(attempt*attempt) * time.Second
-				jitter := time.Duration(float64(delay) * 0.1 * (2*time.Now().UnixNano()%2 - 1))
+				jitter := time.Duration(float64(delay.Nanoseconds()) * 0.1 * float64((time.Now().UnixNano()%2)*2-1))
 				time.Sleep(delay + jitter)
 				
 				log.Infof("Retrying upload attempt %d/%d", attempt+1, maxRetries+1)

test_upload.txt

@@ -0,0 +1 @@
+Hello, HMAC File Server! Do 17. Jul 18:05:48 CEST 2025