follow precedence order as defined in RFC 7232, Section 6

Author: zefir-git

src/Server.ts

@@ -100,32 +100,28 @@ class Server {
             if (etag === null && lastModified === null)
                 break conditional;
 
-            if (req.headers.has("if-match") && !this.getETags(req.headers.get("if-match")!)
-                .filter(t => !t.startsWith("W/"))
-                .includes(etag!))
-                return this.errors._get(ServerErrorRegistry.ErrorCodes.PRECONDITION_FAILED, req)._send(res, this, req);
-
-            if (req.headers.has("if-unmodified-since")
-                && (
-                    lastModified === null
-                    || lastModified.getTime() > new Date(req.headers.get("if-unmodified-since")!).getTime()
-                ))
-                return this.errors._get(ServerErrorRegistry.ErrorCodes.PRECONDITION_FAILED, req)._send(res, this, req);
-            
-            if ((
-                etag !== null
-                && (
-                    req.headers.has("if-none-match")
-                    && this.getETags(req.headers.get("if-none-match")!).includes(etag!)
-                )
-            )
-            || (
-                lastModified !== null
-                && (
-                    req.headers.has("if-modified-since")
-                    && new Date(req.headers.get("if-modified-since")!).getTime() >= lastModified.getTime()
-                )
-            )) return new EmptyResponse(responseHeaders, 304)._send(res, this, req);
+            if (req.headers.has("if-match")) {
+                if (!this.getETags(req.headers.get("if-match")!)
+                    .filter(t => !t.startsWith("W/"))
+                    .includes(etag!))
+                    return this.errors._get(ServerErrorRegistry.ErrorCodes.PRECONDITION_FAILED, req)._send(res, this, req);
+            }
+            else if (req.headers.has("if-unmodified-since")) {
+                if (lastModified === null
+                    || lastModified.getTime() > new Date(req.headers.get("if-unmodified-since")!).getTime())
+                    return this.errors._get(ServerErrorRegistry.ErrorCodes.PRECONDITION_FAILED, req)._send(res, this, req);
+            }
+
+            if (req.headers.has("if-none-match")) {
+                if (this.getETags(req.headers.get("if-none-match")!)
+                    .includes(etag!))
+                    return new EmptyResponse(responseHeaders, 304)._send(res, this, req);
+            }
+            else if (req.headers.has("if-modified-since")) {
+                if (lastModified !== null
+                    && lastModified.getTime() <= new Date(req.headers.get("if-modified-since")!).getTime())
+                    return new EmptyResponse(responseHeaders, 304)._send(res, this, req);
+            }
         }
         response._send(res, this, req);
     }