Kong系列 - 05 - 入门

client：指下游客户端。

service：指上游服务。

route：定义匹配客户端请求的规则，每个路由都与一个服务相关联，而服务可能有多个与之相关联的路由。

plugin：它是在代理生命周期中运行的业务逻辑，插件可以生效于全局或者特定的路由和服务。

consumer：消费者表示服务的消费者或者使用者，可能是一个用户，也可能是一个应用。

下面举一例子。

我们先部署一个echo服务。该服务没有对Kubernetes外暴露端口。如果想从Kubernetes集群之外访问该服务就需要通过Kong网关代理。

vi echo-server-service.yaml
apiVersion: v1
kind: Service
metadata:
  labels:
    app: echo
  name: echo
spec:
  ports:
  - port: 8080
    name: high
    protocol: TCP
    targetPort: 8080
  - port: 80
    name: low
    protocol: TCP
    targetPort: 8080
  selector:
    app: echo
---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: echo
  name: echo
spec:
  replicas: 1
  selector:
    matchLabels:
      app: echo
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: echo
    spec:
      containers:
      - image: e2eteam/echoserver:2.2
        name: echo
        ports:
        - containerPort: 8080
        env:
          - name: NODE_NAME
            valueFrom:
              fieldRef:
                fieldPath: spec.nodeName
          - name: POD_NAME
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: POD_NAMESPACE
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
          - name: POD_IP
            valueFrom:
              fieldRef:
                fieldPath: status.podIP
        resources: {}

为了让Kong感知echo服务，需要在Kong中创建一个服务service，该服务指向echo服务。

curl -X POST \
  --url http://192.168.1.55:32444/services/ \
  --data 'name=echo-service' \
  --data 'url=http://echo:8080' \
  -s | python -m json.tool
{
    "client_certificate": null,
    "connect_timeout": 60000,
    "created_at": 1576504925,
    "host": "echo",
    "id": "f15edf62-cb68-4279-a41f-7f5273ccd001",
    "name": "echo-service",
    "path": null,
    "port": 8080,
    "protocol": "http",
    "read_timeout": 60000,
    "retries": 5,
    "tags": null,
    "updated_at": 1576504925,
    "write_timeout": 60000
}

查询服务services列表，可以看出刚才创建的服务service。

curl -X GET \
  --url http://192.168.1.55:32444/services/ \
  -s | python -m json.tool
{
    "data": [
        {
            "client_certificate": null,
            "connect_timeout": 60000,
            "created_at": 1576504925,
            "host": "echo",
            "id": "f15edf62-cb68-4279-a41f-7f5273ccd001",
            "name": "echo-service",
            "path": null,
            "port": 8080,
            "protocol": "http",
            "read_timeout": 60000,
            "retries": 5,
            "tags": null,
            "updated_at": 1576504925,
            "write_timeout": 60000
        }
    ],
    "next": null
}

为了让Kong知道客户端的哪些请求是访问echo服务的，需要为echo服务添加一条路由。每个服务是可以有多个路由与之对应。

curl -X POST \
  --url http://192.168.1.55:32444/services/echo-service/routes \
  --data 'name=echo-service-route' \
  --data 'paths[]=/foo' \
  -s | python -m json.tool
{
    "created_at": 1576505187,
    "destinations": null,
    "headers": null,
    "hosts": null,
    "https_redirect_status_code": 426,
    "id": "d152f741-9ed1-47d2-98bc-f8c438075e2e",
    "methods": null,
    "name": "echo-service-route",
    "paths": [
        "/foo"
    ],
    "preserve_host": false,
    "protocols": [
        "http",
        "https"
    ],
    "regex_priority": 0,
    "service": {
        "id": "f15edf62-cb68-4279-a41f-7f5273ccd001"
    },
    "snis": null,
    "sources": null,
    "strip_path": true,
    "tags": null,
    "updated_at": 1576505187
}

测试一下，可以看出根据路由能够访问echo服务。

curl -iX GET --url http://192.168.1.55:32080/foo
HTTP/1.1 200 OK
Content-Type: text/plain; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Date: Mon, 16 Dec 2019 14:09:21 GMT
Server: echoserver
X-Kong-Upstream-Latency: 5
X-Kong-Proxy-Latency: 65
Via: kong/1.3.0


Hostname: echo-75cf96d976-pwbg7

Pod Information:
        node name:      k8s-node2
        pod name:       echo-75cf96d976-pwbg7
        pod namespace:  default
        pod IP: 10.244.2.12

Server values:
        server_version=nginx: 1.14.2 - lua: 10015

Request Information:
        client_address=10.244.2.11
        method=GET
        real path=/
        query=
        request_version=1.1
        request_scheme=http
        request_uri=http://echo:8080/

Request Headers:
        accept=*/*
        connection=keep-alive
        host=echo:8080
        user-agent=curl/7.29.0
        x-forwarded-for=10.244.0.0
        x-forwarded-host=192.168.1.55
        x-forwarded-port=8000
        x-forwarded-proto=http
        x-real-ip=10.244.0.0

Request Body:
        -no body in request-