fix: add x_request_id for server_span match

app/app/application/l7_flow_tracing.py

@@ -1547,8 +1547,11 @@ def __init__(self, group_key: str):
         self.app_span_roots: List[SpanNode] = None
         # 用于存放 `app_span` 的所有 leaf
         self.app_span_leafs: List[SpanNode] = None
+        # 记录叶子节点的 syscall_trace_id, 用以匹配 s-p root
         self.leaf_syscall_trace_id_request: Set[int] = set()
         self.leaf_syscall_trace_id_response: Set[int] = set()
+        # 记录叶子节点的 x_request_id => index (in self.spans), 用以匹配 s-p root
+        self.leaf_x_request_id: Dict[str, List[int]] = {}
         # 用于显示调用拓扑使用
         self.subnet_id = None
         self.subnet = None
@@ -1659,10 +1662,23 @@ def append_sys_span(self, sys_span: SysSpanNode):
         self._set_extra_value_for_sys_span(sys_span)
         self._set_auto_service(sys_span)
         if sys_span.tap_side == TAP_SIDE_CLIENT_PROCESS:
-            self.leaf_syscall_trace_id_request.add(
-                sys_span.get_syscall_trace_id_request())
-            self.leaf_syscall_trace_id_response.add(
-                sys_span.get_syscall_trace_id_response())
+            cp_syscall_trace_id_req = sys_span.get_syscall_trace_id_request()
+            cp_syscall_trace_id_res = sys_span.get_syscall_trace_id_response()
+            cp_x_request_id_0 = sys_span.get_x_request_id_0()
+            cp_x_request_id_1 = sys_span.get_x_request_id_1()
+            if cp_syscall_trace_id_req:
+                self.leaf_syscall_trace_id_request.add(
+                    sys_span.get_syscall_trace_id_request())
+            if cp_syscall_trace_id_res:
+                self.leaf_syscall_trace_id_response.add(
+                    sys_span.get_syscall_trace_id_response())
+            if cp_x_request_id_0:
+                # index of sys_span = len(self.spans)-1
+                self.leaf_x_request_id.setdefault(
+                    cp_x_request_id_0, []).append(len(self.spans) - 1)
+            if cp_x_request_id_1 and cp_x_request_id_1 != cp_x_request_id_0:
+                self.leaf_x_request_id.setdefault(
+                    cp_x_request_id_1, []).append(len(self.spans) - 1)
 
     def remove_server_sys_span(self, sys_span: SysSpanNode):
         # 这里应该要做 append_sys_span 的逆操作(但对象仅为 ServerProcess sys_span)
@@ -1743,7 +1759,7 @@ def split_to_multiple_process_span_set(self) -> list:
             # 极端情况下可能会有多个没有 parent_span_id 的入口，这里没法分辨它们的关系，不做拆分
             if root_parent_span_id == '':
                 root_parent_span_id = "root"  # 只是标记 root_parent_span_id，没有实际作用
-            if root_parent_span_id not in split_result:
+            if split_result.get(root_parent_span_id, None) is None:
                 newSet = ProcessSpanSet(root_parent_span_id)
                 newSet.app_span_roots = [self.spans[root_span_index]]
                 newSet._copy_meta_data_from(self)
@@ -1776,7 +1792,12 @@ def attach_sys_span_via_app_span(self, sys_span: SysSpanNode) -> bool:
             return self._attach_client_sys_span(sys_span)
 
     def _attach_server_sys_span(self, sys_span: SysSpanNode) -> bool:
+        # connection priority: span_id > syscall_trace_id > x_request_id
         span_id_of_sys_span = sys_span.get_span_id()
+        syscall_trace_id_request = sys_span.get_syscall_trace_id_request()
+        syscall_trace_id_response = sys_span.get_syscall_trace_id_response()
+        x_request_id_0 = sys_span.get_x_request_id_0()
+        x_request_id_1 = sys_span.get_x_request_id_1()
         if span_id_of_sys_span:
             for app_root in self.app_span_roots:
                 if span_id_of_sys_span == app_root.get_parent_span_id():
@@ -1815,10 +1836,9 @@ def _attach_server_sys_span(self, sys_span: SysSpanNode) -> bool:
                                 "s-p sys_span mounted due to same span_id as parent",
                                 self.mounted_callback)
                         return True
-        else:
-            syscall_trace_id_request = sys_span.get_syscall_trace_id_request()
-            syscall_trace_id_response = sys_span.get_syscall_trace_id_response(
-            )
+
+        # span_id not matched, try syscall_trace_id
+        if syscall_trace_id_request or syscall_trace_id_response:
             for app_root in self.app_span_roots:
                 # 如果 span_id 不存在，说明可能是入口 span，上游没有注入 span_id，此时根据叶子节点 c-p 的 syscall_trace_id 匹配即可
                 # 这里匹配可以严格点，s-p 和 c-p 只会同侧(req-req / res-res)相等，避免误关联一个独立的 c-p
@@ -1830,6 +1850,36 @@ def _attach_server_sys_span(self, sys_span: SysSpanNode) -> bool:
                         "s-p sys_span mounted due to syscall_trace_id matched c-p",
                         self.mounted_callback)
                     return True
+
+        # span_id/syscall not matched, try x_request_id
+        if x_request_id_0 or x_request_id_1:
+            # 场景：过 ingress/nginx 进入服务网关/服务，传递了 x_request_id，且作为首个 span 没有 trace_id/span_id
+            # 且发生跨线程调度，无法基于 syscall 关联时，允许通过 s-p.x_request_id(0/1) <=> c-p.x_request_id(0/1) 关联
+            # 此处已确保 auto_instance_id 一致 （即同一个进程）
+
+            # x_req_id 同侧相等: 透传 x_req_id，来自上游
+            # x_req_id 异侧相等: 注入 x_req_id，内部产生
+            x_req_id_matched = False
+            # 同一个进程内时间一定覆盖
+            for same_xreqid_idx in self.leaf_x_request_id.get(
+                    x_request_id_0, []):
+                if sys_span.time_range_cover(self.spans[same_xreqid_idx]):
+                    x_req_id_matched = True
+            if not x_req_id_matched:
+                for same_xreqid_idx in self.leaf_x_request_id.get(
+                        x_request_id_1, []):
+                    if sys_span.time_range_cover(self.spans[same_xreqid_idx]):
+                        x_req_id_matched = True
+            if x_req_id_matched:
+                for app_root in self.app_span_roots:
+                    if app_root.get_parent_id() < 0:
+                        self.append_sys_span(sys_span)
+                        app_root.set_parent(
+                            sys_span,
+                            "s-p sys_span mounted due to x_request_id matched c-p",
+                            self.mounted_callback)
+                        return True
+
         return False
 
     def _attach_client_sys_span(self, sys_span: SysSpanNode) -> bool: