前端代理 · ENVOY 智能代理中文参考文档

## 前端代理为让大家尽快了解Envoy如何作为前端代理，我们发布了一个[docker compose](https://docs.docker.com/compose/)沙箱，这个沙箱部署了一个前端Envoy代理和几个后端服务（简单的flask应用），并与一个正在运行的合作的Envoy服务。这三个容器将部署在名为`envoymesh`的虚拟网格中。该Docker compose的部署图如下所示： ![部署图](docker_compose_v0.1.svg) 所有传入的请求都通过前端Envoy进行路由，该Envoy充当位于`envoymesh`网络边缘的反向代理。端口`80`通过docker compose映射到端口`8000`（请参阅[/examples/front-proxy/docker-compose.yml](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/docker-compose.yml)）。此外，请注意，由前端Envoy路由到容器内的服务，实际上所有流量都是路由到服务的Envoy代理（在[/examples/front-proxy/front-envoy.json](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/front-envoy.json)中设置的路由）。反过来，服务的Envoy通过环回地址（[/examples/front-proxy/service-envoy.json](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/service-envoy.json)中的路由设置）将请求路由到flask应用程序。此阐述了Envoy与您服务搭配的优势：所有请求都由Envoy代理，并有效地路由到您的服务。 ### 运行沙箱以下文档将按照上图中所述的envoy集群进行运行设置。 **第1步：安装Docker工具集** 请您确保已经安装了最新版本的`docker`，`docker-compose`和`docker-machine`。 [Docker工具箱](https://www.docker.com/products/docker-toolbox)提供了简单的方法来获取这些工具。 **第2步：设置Docker Machine** 首先让我们创建一个新的机器来容纳容器： ``` $ docker-machine create --driver virtualbox default $ eval $(docker-machine env default) ``` **第3步：建立本地Envoy克隆仓库，并启动所有的容器** 如果你还没有克隆Envoy仓库，请用git克隆`git clone git@github.com:envoyproxy/envoy`或者`git clone https://github.com/envoyproxy/envoy.git`： ``` $ pwd envoy/examples/front-proxy $ docker-compose up --build -d $ docker-compose ps Name Command State Ports ------------------------------------------------------------------------------------------------------------- example_service1_1 /bin/sh -c /usr/local/bin/ ... Up 80/tcp example_service2_1 /bin/sh -c /usr/local/bin/ ... Up 80/tcp example_front-envoy_1 /bin/sh -c /usr/local/bin/ ... Up 0.0.0.0:8000->80/tcp, 0.0.0.0:8001->8001/tcp ``` **第4步：测试Envoy的路由功能** 您现在可以通过前端Envoy向两个服务发送请求。对于service1： ``` $ curl -v $(docker-machine ip default):8000/service/1 * Trying 192.168.99.100... * Connected to 192.168.99.100 (192.168.99.100) port 8000 (#0) > GET /service/1 HTTP/1.1 > Host: 192.168.99.100:8000 > User-Agent: curl/7.43.0 > Accept: */* > < HTTP/1.1 200 OK < content-type: text/html; charset=utf-8 < content-length: 89 < x-envoy-upstream-service-time: 1 < server: envoy < date: Fri, 26 Aug 2016 19:39:19 GMT < x-envoy-protocol-version: HTTP/1.1 < Hello from behind Envoy (service 1)! hostname: f26027f1ce28 resolvedhostname: 172.19.0.6 * Connection #0 to host 192.168.99.100 left intact ``` 对于service2： ``` $ curl -v $(docker-machine ip default):8000/service/2 * Trying 192.168.99.100... * Connected to 192.168.99.100 (192.168.99.100) port 8000 (#0) > GET /service/2 HTTP/1.1 > Host: 192.168.99.100:8000 > User-Agent: curl/7.43.0 > Accept: */* > < HTTP/1.1 200 OK < content-type: text/html; charset=utf-8 < content-length: 89 < x-envoy-upstream-service-time: 2 < server: envoy < date: Fri, 26 Aug 2016 19:39:23 GMT < x-envoy-protocol-version: HTTP/1.1 < Hello from behind Envoy (service 2)! hostname: 92f4a3737bbc resolvedhostname: 172.19.0.2 * Connection #0 to host 192.168.99.100 left intact ``` 请注意，每个请求在发送给前端Envoy时，已正确路由到相应的应用程序。 **第5步：测试Envoy的负载均衡能力** 现在扩展我们的service1节点来演示Envoy的集群能力。 ``` $ docker-compose scale service1=3 Creating and starting example_service1_2 ... done Creating and starting example_service1_3 ... done ``` 现在，如果我们多次向service1发送请求，前端Envoy会将请求通过负载均衡发给三个service1服务： ``` $ curl -v $(docker-machine ip default):8000/service/1 * Trying 192.168.99.100... * Connected to 192.168.99.100 (192.168.99.100) port 8000 (#0) > GET /service/1 HTTP/1.1 > Host: 192.168.99.100:8000 > User-Agent: curl/7.43.0 > Accept: */* > < HTTP/1.1 200 OK < content-type: text/html; charset=utf-8 < content-length: 89 < x-envoy-upstream-service-time: 1 < server: envoy < date: Fri, 26 Aug 2016 19:40:21 GMT < x-envoy-protocol-version: HTTP/1.1 < Hello from behind Envoy (service 1)! hostname: 85ac151715c6 resolvedhostname: 172.19.0.3 * Connection #0 to host 192.168.99.100 left intact $ curl -v $(docker-machine ip default):8000/service/1 * Trying 192.168.99.100... * Connected to 192.168.99.100 (192.168.99.100) port 8000 (#0) > GET /service/1 HTTP/1.1 > Host: 192.168.99.100:8000 > User-Agent: curl/7.43.0 > Accept: */* > < HTTP/1.1 200 OK < content-type: text/html; charset=utf-8 < content-length: 89 < x-envoy-upstream-service-time: 1 < server: envoy < date: Fri, 26 Aug 2016 19:40:22 GMT < x-envoy-protocol-version: HTTP/1.1 < Hello from behind Envoy (service 1)! hostname: 20da22cfc955 resolvedhostname: 172.19.0.5 * Connection #0 to host 192.168.99.100 left intact $ curl -v $(docker-machine ip default):8000/service/1 * Trying 192.168.99.100... * Connected to 192.168.99.100 (192.168.99.100) port 8000 (#0) > GET /service/1 HTTP/1.1 > Host: 192.168.99.100:8000 > User-Agent: curl/7.43.0 > Accept: */* > < HTTP/1.1 200 OK < content-type: text/html; charset=utf-8 < content-length: 89 < x-envoy-upstream-service-time: 1 < server: envoy < date: Fri, 26 Aug 2016 19:40:24 GMT < x-envoy-protocol-version: HTTP/1.1 < Hello from behind Envoy (service 1)! hostname: f26027f1ce28 resolvedhostname: 172.19.0.6 * Connection #0 to host 192.168.99.100 left intact ``` **第6步：进入容器开启curl服务** 除了使用主机上的curl外，您还可以自己输入容器并从里面curl。要输入一个容器镜像，你可以使用`docker-compose exec <container_name> /bin/bash`。例如，我们可以进入`front-envoy`容器，并在执行本地的curl服务： ``` $ docker-compose exec front-envoy /bin/bash root@81288499f9d7:/# curl localhost:80/service/1 Hello from behind Envoy (service 1)! hostname: 85ac151715c6 resolvedhostname: 172.19.0.3 root@81288499f9d7:/# curl localhost:80/service/1 Hello from behind Envoy (service 1)! hostname: 20da22cfc955 resolvedhostname: 172.19.0.5 root@81288499f9d7:/# curl localhost:80/service/1 Hello from behind Envoy (service 1)! hostname: f26027f1ce28 resolvedhostname: 172.19.0.6 root@81288499f9d7:/# curl localhost:80/service/2 Hello from behind Envoy (service 2)! hostname: 92f4a3737bbc resolvedhostname: 172.19.0.2 ``` **第7步：进入容器和使用curl管理** 当Envoy运行时，它也将`admin`连接到所需的端口。在示例配置`admin`被绑定到`8001`端口.我们可以`curl`它获得有用的信息。例如，您可以`curl` `/server_info`来获取有关您正在运行的Envoy版本信息。另外，你可以·curl· ·/stats·得到统计数据。例如在`frontenvoy`里面我们可以得到： ``` $ docker-compose exec front-envoy /bin/bash root@e654c2c83277:/# curl localhost:8001/server_info envoy 10e00b/RELEASE live 142 142 0 root@e654c2c83277:/# curl localhost:8001/stats cluster.service1.external.upstream_rq_200: 7 ... cluster.service1.membership_change: 2 cluster.service1.membership_total: 3 ... cluster.service1.upstream_cx_http2_total: 3 ... cluster.service1.upstream_rq_total: 7 ... cluster.service2.external.upstream_rq_200: 2 ... cluster.service2.membership_change: 1 cluster.service2.membership_total: 1 ... cluster.service2.upstream_cx_http2_total: 1 ... cluster.service2.upstream_rq_total: 2 ... ``` 请注意，我们还可以获得上游群集的成员数量，完成的请求数量，有关http入站的信息以及其他大量有用的统计信息。 ## 返回 - [上一级](../Sandboxes.md) - [首页目录](../../README.md)