前端代理 · ENVOY 智能代理中文參考文檔

## 前端代理為讓大家盡快了解Envoy如何作為前端代理，我們發布了一個[docker compose](https://docs.docker.com/compose/)沙箱，這個沙箱部署了一個前端Envoy代理和幾個后端服務（簡單的flask應用），并與一個正在運行的合作的Envoy服務。這三個容器將部署在名為`envoymesh`的虛擬網格中。該Docker compose的部署圖如下所示： ![部署圖](docker_compose_v0.1.svg) 所有傳入的請求都通過前端Envoy進行路由，該Envoy充當位于`envoymesh`網絡邊緣的反向代理。端口`80`通過docker compose映射到端口`8000`（請參閱[/examples/front-proxy/docker-compose.yml](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/docker-compose.yml)）。此外，請注意，由前端Envoy路由到容器內的服務，實際上所有流量都是路由到服務的Envoy代理（在[/examples/front-proxy/front-envoy.json](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/front-envoy.json)中設置的路由）。反過來，服務的Envoy通過環回地址（[/examples/front-proxy/service-envoy.json](https://github.com/envoyproxy/envoy/blob/master//examples/front-proxy/service-envoy.json)中的路由設置）將請求路由到flask應用程序。此闡述了Envoy與您服務搭配的優勢：所有請求都由Envoy代理，并有效地路由到您的服務。 ### 運行沙箱以下文檔將按照上圖中所述的envoy集群進行運行設置。 **第1步：安裝Docker工具集** 請您確保已經安裝了最新版本的`docker`，`docker-compose`和`docker-machine`。 [Docker工具箱](https://www.docker.com/products/docker-toolbox)提供了簡單的方法來獲取這些工具。 **第2步：設置Docker Machine** 首先讓我們創建一個新的機器來容納容器： ``` $ docker-machine create --driver virtualbox default $ eval $(docker-machine env default) ``` **第3步：建立本地Envoy克隆倉庫，并啟動所有的容器** 如果你還沒有克隆Envoy倉庫，請用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：測試Envoy的路由功能** 您現在可以通過前端Envoy向兩個服務發送請求。對于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 ``` 對于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 ``` 請注意，每個請求在發送給前端Envoy時，已正確路由到相應的應用程序。 **第5步：測試Envoy的負載均衡能力** 現在擴展我們的service1節點來演示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 ``` 現在，如果我們多次向service1發送請求，前端Envoy會將請求通過負載均衡發給三個service1服務： ``` $ 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：進入容器開啟curl服務** 除了使用主機上的curl外，您還可以自己輸入容器并從里面curl。要輸入一個容器鏡像，你可以使用`docker-compose exec <container_name> /bin/bash`。例如，我們可以進入`front-envoy`容器，并在執行本地的curl服務： ``` $ 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：進入容器和使用curl管理** 當Envoy運行時，它也將`admin`連接到所需的端口。在示例配置`admin`被綁定到`8001`端口.我們可以`curl`它獲得有用的信息。例如，您可以`curl` `/server_info`來獲取有關您正在運行的Envoy版本信息。另外，你可以·curl· ·/stats·得到統計數據。例如在`frontenvoy`里面我們可以得到： ``` $ 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 ... ``` 請注意，我們還可以獲得上游群集的成員數量，完成的請求數量，有關http入站的信息以及其他大量有用的統計信息。 ## 返回 - [上一級](../Sandboxes.md) - [首頁目錄](../../README.md)