Envoy里流式协议的数据流
目录
定义后端服务
先用protobuf定义你的服务。该服务有一个双向流API BiStream。
syntax = "proto3";
package api;
option go_package = "envoystreaming/api";
service StreamService {
rpc BiStream(stream Data) returns (stream Data);
}
message Data { string body = 1; }提示
为了使Go服务能识别到你定义的服务。你需要先运行下面的代码生成服务定义。执行之后，你会看到他生成了名为stream_grpc.pb.go的Go语言服务定义。
protoc --go_out=. --go_opt=paths=source_relative \
--go-grpc_out=. --go-grpc_opt=paths=source_relative \
api/stream.proto然后我门用Go语言实现该服务。该服务按顺序从输入流中轮询发送过来的数据。当他发现有数据发送过来的时候，间隔5秒发送一个ACK响应，一共发三个。
package main
import (
"io"
"log"
"net"
"time"
"envoystreaming/api"
"google.golang.org/grpc"
"google.golang.org/grpc/reflection"
)
type server struct {
api.UnimplementedStreamServiceServer
}
func (s *server) BiStream(stream api.StreamService_BiStreamServer) error {
for {
req, err := stream.Recv()
if err == io.EOF {
return nil
}
if err != nil {
return err
}
log.Printf("[Backend] Recv: %s", req.Body)
// 模拟流速控制：每 5000ms 回复一个，模拟流式下发
for i := 1; i < 3; i++ {
time.Sleep(5000 * time.Millisecond)
err := stream.Send(&api.Data{Body: "ACK-" + req.Body})
if err != nil {
return err
}
}
}
}
func main() {
lis, _ := net.Listen("tcp", ":50051")
s := grpc.NewServer()
api.RegisterStreamServiceServer(s, &server{})
reflection.Register(s) // 使用反射方便查看API
log.Println("Backend listening on :50051...")
s.Serve(lis)
}protoc --go_out=. --go_opt=paths=source_relative \
--go-grpc_out=. --go-grpc_opt=paths=source_relative \
api/stream.proto
}实现之后我们先来测试后端服务器是可以跑通的。执行下面的命令开启后端服务。后端服务会跑在端口50051上。服务器的日志会直接打印在stdout。
go run backend/main.go然后我们使用grpccurl工具向该后端服务发送请求。
你可以选择只发一个请求。
grpcurl -plaintext -proto ./api/stream.proto -d '{"body": "hello"}' localhost:50051 api.StreamService/BiStream也可以选择开启一个连接，然后发送多个请求。
grpcurl -plaintext -proto ./api/stream.proto -d @ localhost:8080 api.StreamService/BiStream你可以持续不断地发送请求。后端服务器会依次响应。
提示
如果你不确定自己定义的API方法是什么，你可以用
grpcurl -plaintext localhost:50051 list 查看你所有的API方法。我们可以看到如下响应。
客户端：
zheyu@ZhedeAir envoystreaming % grpcurl -plaintext -proto ./api/stream.proto -d @ localhost:50051 api.StreamService/BiStream
{"body": "hello2"}
{
"body": "ACK-hello2"
}
{
"body": "ACK-hello2"
}
{
"body": "ACK-hello2"
}
{"body": "hello3"}
{
"body": "ACK-hello3"
}
{
"body": "ACK-hello3"
}
{
"body": "ACK-hello3"
}服务器端：
zheyu@ZhedeAir envoystreaming % go run backend/main.go
2026/04/10 11:30:52 Backend listening on :50051...
2026/04/10 11:30:58 [Backend] Recv: hello2
2026/04/10 11:31:32 [Backend] Recv: hello3定义filter
这里为了观察数据流的流动，我们使用cpp语言定义3个相同的Wasm filter。
#include <string>
#include "proxy_wasm_intrinsics.h"
class MyStreamContext : public Context {
public:
explicit MyStreamContext(uint32_t id, RootContext* root) : Context(id, root) {}
// --- Request Path ---
FilterHeadersStatus onRequestHeaders(uint32_t headers, bool end_stream) override {
LOG_INFO("C++ Filter >>> Request Headers received");
return FilterHeadersStatus::Continue;
}
FilterDataStatus onRequestBody(size_t body_buffer_length, bool end_stream) override {
LOG_INFO("C++ Filter >>> Request Body (size: " + std::to_string(body_buffer_length) + ")");
return FilterDataStatus::Continue;
}
// --- Response Path ---
FilterHeadersStatus onResponseHeaders(uint32_t headers, bool end_stream) override {
LOG_INFO("C++ Filter <<< Response Headers received");
return FilterHeadersStatus::Continue;
}
FilterDataStatus onResponseBody(size_t body_buffer_length, bool end_stream) override {
LOG_INFO("C++ Filter <<< Response Body (size: " + std::to_string(body_buffer_length) + ")");
return FilterDataStatus::Continue;
}
};
static RegisterContextFactory register_MyStreamContext(CONTEXT_FACTORY(MyStreamContext));然后我们使用Docker构建Wasm filter。注意我们这里使用了下载到本地的proxy-wasm-cpp-sdk。下面的命令将构建filter.wasm文件。
docker run --rm -v $(pwd):/src -u $(id -u):$(id -g) \
emscripten/emsdk emcc -O3 \
filter.cc \
proxy-wasm-cpp-sdk/proxy_wasm_intrinsics.cc \
-I/src/proxy-wasm-cpp-sdk \
-o filter.wasm \
-s STANDALONE_WASM \
-s ERROR_ON_UNDEFINED_SYMBOLS=0 \
-s EXPORTED_FUNCTIONS="['_malloc','_free']" \
--no-entry然后我们使用下面的Envoy定义来开启一个Envoy实例。请注意以下要点。
- filter的
root_id字段必须为空。否则将和filter代码里面的root不匹配。注意此时的filter代码里root没有被设置。 - filter的code位置我们必须设置为
/etc/envoy/filter.wasm,这是因为在下一步我们将会在Docker里面运行Envoy实例，Docker没有办法感知我们当前项目的位置。 - cluster的
address必须设置为host.docker.internal。如果设置为本地地址127.0.0.1，它访问的是容器内部的Loopback。而Go后端运行在Mac宿主机上。它们就像在两个平行的时空，互相看不见。 - cluster的
type字段必须设置为LOGICAL_DNS。这是因为假如使用STATIC(默认)，Envoy认为address字段里填的必须是一个可以直接使用的 IP地址。然后它试图直接调用操作系统的网络接口去连接，看到host.docker.internal这一串字母时，它会觉得这“不像一个 IP”，所以会识别不了。当我们使用LOGICAL_DNS后，Envoy 会在启动以及运行期间，定期去调用 DNS 解析（在容器里会询问 Docker 的内置 DNS 服务器），将host.docker.internal转换成宿主机的真实 IP。
static_resources:
listeners:
- name: listener_0
address:
socket_address: { address: 0.0.0.0, port_value: 8080 }
filter_chains:
- filters:
- name: envoy.filters.network.http_connection_manager
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
stat_prefix: ingress_http
http_filters:
- name: envoy.filters.http.wasm
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.http.wasm.v3.Wasm
config:
name: "my_filter_1"
root_id: ""
configuration:
"@type": "type.googleapis.com/google.protobuf.StringValue"
value: "any_config"
vm_config:
vm_id: "my_vm_1"
runtime: "envoy.wasm.runtime.v8"
code:
local:
filename: "/etc/envoy/filter.wasm"
- name: envoy.filters.http.wasm
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.http.wasm.v3.Wasm
config:
name: "my_filter_2"
root_id: ""
configuration:
"@type": "type.googleapis.com/google.protobuf.StringValue"
value: "any_config"
vm_config:
vm_id: "my_vm_1"
runtime: "envoy.wasm.runtime.v8"
code:
local:
filename: "/etc/envoy/filter.wasm"
- name: envoy.filters.http.wasm
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.http.wasm.v3.Wasm
config:
name: "my_filter_3"
root_id: ""
configuration:
"@type": "type.googleapis.com/google.protobuf.StringValue"
value: "any_config"
vm_config:
vm_id: "my_vm_1"
runtime: "envoy.wasm.runtime.v8"
code:
local:
filename: "/etc/envoy/filter.wasm"
- name: envoy.filters.http.router
typed_config: { "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router }
route_config:
name: local_route
virtual_hosts:
- name: local_service
domains: ["*"]
routes:
- match: { prefix: "/" }
route: { cluster: grpc_backend }
clusters:
- name: grpc_backend
type: LOGICAL_DNS
http2_protocol_options: {}
load_assignment:
cluster_name: grpc_backend
endpoints:
- lb_endpoints:
- endpoint: { address: { socket_address: { address: host.docker.internal, port_value: 50051 } } }现在我们用下面的命令在Docker里面启动一个Envoy实例，观察数据流运动结果。
DOCKER_API_VERSION=1.40 docker run --rm -it \
-v $(pwd)/envoy.yaml:/etc/envoy/envoy.yaml \
-v $(pwd)/filtercpp/filter.wasm:/etc/envoy/filter.wasm \
-v $(pwd)/filtercpp/slowfilter.wasm:/etc/envoy/slowfilter.wasm \
-p 8080:8080 \
envoyproxy/envoy-contrib:v1.30-latest \
envoy -c /etc/envoy/envoy.yaml -l info实验结果
Happy case
当我们使用如下命令建立连接，但是不发送数据的时候，我们看到客户端发送了Header建立了连接。
[2026-04-10 22:02:39.622][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 22:02:39.622][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 22:02:39.622][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received我们用下面的参数输出debug日志后，我们可以看到在得到Header之前downstream和Envoy建立了连接和一个新的stream。注意此时的connection Id为0，end_stream为false。并且我们看到了envoy
[2026-04-21 01:13:58.669][27][debug][conn_handler] [source/common/listener_manager/active_tcp_listener.cc:160] [Tags: "ConnectionId":"0"] new connection from 192.168.65.1:64799
[2026-04-21 01:13:58.674][27][debug][http] [source/common/http/conn_manager_impl.cc:398] [Tags: "ConnectionId":"0"] new stream
[2026-04-21 01:13:58.674][27][debug][http2] [source/common/http/http2/codec_impl.cc:1942] [Tags: "ConnectionId":"0"] Http2Visitor::OnEndHeadersForStream(1)
[2026-04-21 01:13:58.674][27][debug][http] [source/common/http/conn_manager_impl.cc:1147] [Tags: "ConnectionId":"0","StreamId":"8538165979598051927"] request headers complete (end_stream=false):
':method', 'POST'
':scheme', 'http'
':path', '/api.StreamService/BiStream'
':authority', 'localhost:8080'
'content-type', 'application/grpc'
'user-agent', 'grpcurl/1.9.3 grpc-go/1.61.0'
'te', 'trailers'
'grpc-accept-encoding', 'gzip'在Header流过Wasm filter之后，我门看到Envoy正在试图做routing决定。然后我门看到Envoy创建了一个连接到upstream。然后又给这个连接创建了一个stream。
[2026-04-21 01:13:58.677][27][debug][router] [source/common/router/router.cc:515] [Tags: "ConnectionId":"0","StreamId":"8538165979598051927"] cluster 'grpc_backend' match for URL '/api.StreamService/BiStream'
[2026-04-21 01:13:58.677][27][debug][router] [source/common/router/router.cc:738] [Tags: "ConnectionId":"0","StreamId":"8538165979598051927"] router decoding headers:
':method', 'POST'
':scheme', 'http'
':path', '/api.StreamService/BiStream'
':authority', 'localhost:8080'
'content-type', 'application/grpc'
'user-agent', 'grpcurl/1.9.3 grpc-go/1.61.0'
'te', 'trailers'
'grpc-accept-encoding', 'gzip'
'x-forwarded-proto', 'http'
'x-request-id', 'aeca9b84-34fd-4758-bb5b-c2323ff369bd'
'x-envoy-expected-rq-timeout-ms', '15000'
[2026-04-21 01:13:58.678][27][debug][pool] [source/common/conn_pool/conn_pool_base.cc:291] trying to create new connection
[2026-04-21 01:13:58.678][27][debug][pool] [source/common/conn_pool/conn_pool_base.cc:145] creating a new connection (connecting=0)
[2026-04-21 01:13:58.678][27][debug][http2] [source/common/http/http2/codec_impl.cc:1720] [Tags: "ConnectionId":"1"] updating connection-level initial window size to 268435456
[2026-04-21 01:13:58.678][27][debug][connection] [./source/common/network/connection_impl.h:98] [Tags: "ConnectionId":"1"] current connecting state: true
[2026-04-21 01:13:58.678][27][debug][client] [source/common/http/codec_client.cc:57] [Tags: "ConnectionId":"1"] connecting
[2026-04-21 01:13:58.678][27][debug][connection] [source/common/network/connection_impl.cc:1021] [Tags: "ConnectionId":"1"] connecting to 192.168.65.254:7580
[2026-04-21 01:13:58.679][27][debug][connection] [source/common/network/connection_impl.cc:1040] [Tags: "ConnectionId":"1"] connection in progress
[2026-04-21 01:13:58.683][27][debug][connection] [source/common/network/connection_impl.cc:751] [Tags: "ConnectionId":"1"] connected
[2026-04-21 01:13:58.683][27][debug][client] [source/common/http/codec_client.cc:88] [Tags: "ConnectionId":"1"] connected
[2026-04-21 01:13:58.683][27][debug][pool] [source/common/conn_pool/conn_pool_base.cc:328] [Tags: "ConnectionId":"1"] attaching to next stream
[2026-04-21 01:13:58.683][27][debug][pool] [source/common/conn_pool/conn_pool_base.cc:182] [Tags: "ConnectionId":"1"] creating stream当我们开始发送数据{"body": "hello}，我们看到后端首先发回Header，然后发回三个响应体。注意请求和响应流过filter的顺序是正好相反的。
[2026-04-10 22:04:21.209][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:21.210][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:21.210][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:26.223][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 22:04:26.223][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 22:04:26.223][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 22:04:26.224][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:26.224][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:26.224][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:31.219][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:31.219][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:31.219][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:36.221][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:36.221][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:36.221][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:52.293][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:52.294][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:52.294][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:15]::onRequestBody() C++ Filter >>> Request Body (size: 16)
[2026-04-10 22:04:57.298][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:57.298][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:04:57.298][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:02.299][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:02.299][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:02.299][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:07.300][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:07.300][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)
[2026-04-10 22:05:07.300][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:26]::onResponseBody() C++ Filter <<< Response Body (size: 20)为什么后端没有立即发回响应的Header？这是因为在gRPC框架中，后端不会在建立连接后就立即发送响应Header。当后端的Go代码执行到stream.Send()时，gRPC框架才发现这是本流的第一次下发数据，它会先自动封装一个响应Headers（HTTP 200, content-type: application/grpc 等）发出去，紧接着再发送数据帧。我们可以用下面的方法验证。
首先在Go后端BiStream方法的最开始加上下面的代码。下面的代码将打印stream信息。
ctx := stream.Context()
// 1. 打印元数据 (Headers)
if md, ok := metadata.FromIncomingContext(ctx); ok {
log.Printf("[Stream Info] Metadata: %v", md)
}
// 2. 打印客户端地址
if p, ok := peer.FromContext(ctx); ok {
log.Printf("[Stream Info] Remote Addr: %s", p.Addr.String())
}然后在两个不同的终端运行下面的命令连接。发现Go后端分别建立了两个连接。每个连接的stream id和客户端地址都不同。
grpcurl -plaintext -proto ./api/stream.proto -d @ localhost:8080 api.StreamService/BiStream2026/04/10 15:31:36 [Stream Info] Metadata: map[:authority:[localhost:8080] content-type:[application/grpc] grpc-accept-encoding:[gzip] user-agent:[grpcurl/1.9.3 grpc-go/1.61.0] x-envoy-expected-rq-timeout-ms:[15000] x-forwarded-proto:[http] x-request-id:[36a02abb-89e2-455e-ac4e-2996519d489d]]
2026/04/10 15:31:36 [Stream Info] Remote Addr: 127.0.0.1:59312
2026/04/10 15:31:40 [Stream Info] Metadata: map[:authority:[localhost:8080] content-type:[application/grpc] grpc-accept-encoding:[gzip] user-agent:[grpcurl/1.9.3 grpc-go/1.61.0] x-envoy-expected-rq-timeout-ms:[15000] x-forwarded-proto:[http] x-request-id:[d0b8dbc1-7e3b-45e6-a5ce-08ec760427d9]]
2026/04/10 15:31:40 [Stream Info] Remote Addr: 127.0.0.1:59316下面我们尝试在连接建立后直接发送一个Header，不等第一个请求题到来。可以看到响应头直接返回，不需要第一个请求头。
[2026-04-10 22:40:11.520][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 22:40:11.520][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 22:40:11.520][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 22:40:11.527][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 22:40:11.527][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 22:40:11.527][30][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:21]::onResponseHeaders() C++ Filter <<< Response Headers received如果我们此时直接发一个请求，并立即关闭连接你会看到如下日志。
zheyu@ZhedeAir envoystreaming % grpcurl -plaintext -proto ./api/stream.proto -d '{"body": "hello"}' localhost:8080 api.StreamService/BiStream
{
"body": "ACK-hello"
}
{
"body": "ACK-hello"
}
{
"body": "ACK-hello"
}[2026-04-10 23:17:37.601][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 23:17:37.601][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 23:17:37.601][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:10]::onRequestHeaders() C++ Filter >>> Request Headers received
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 12)
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 12)
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 12)
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 0)
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 0)
[2026-04-10 23:17:37.604][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:16]::onRequestBody() C++ Filter >>> Request Body (size: 0)
[2026-04-10 23:17:38.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:23]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 23:17:38.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:23]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 23:17:38.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:23]::onResponseHeaders() C++ Filter <<< Response Headers received
[2026-04-10 23:17:38.115][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:38.115][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:38.115][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:38.612][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:38.612][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:38.612][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:39.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_3 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:39.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_2 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)
[2026-04-10 23:17:39.114][31][info][wasm] [source/extensions/common/wasm/context.cc:1195] wasm log my_filter_1 my_vm_1: [filter.cc:29]::onResponseBody() C++ Filter <<< Response Body (size: 16)你会看到在size为12的请求体之后一个一个size为0的请求体。该请求体是我们在发送了gRPC数据帧后面的http2数据帧。该数据帧有END_STREAM标志。这是因为我们用的-d，他会在发送完数据之后立即请求关闭连接。
注意
当你直接发送一个请求并立即关闭的情况下，最好将发送响应的间隔变小。否则可能会发生请求端请求了关闭但是响应流正在休眠的情况