简介APISIX 是动态、实时、高性能的 API 网关。它提供丰富的流量管理功能，比如负载均衡、动态上游、金丝雀发布、熔断、认证、可观测性等。既可以使用 APISIX API 网关处理传统的南北向流量，也可以使用它处理服务间的东西向流量。同时，它也可被用作 Kubernetes Ingress 控制器。APISIX Ingress 控制器提供 Helm 安装方式，但是使用原生 YAML 安装，更加有助于理解其原理。使用原生 YAML 安装 APISIX 和 APISIX Ingress 控制器在本教程中，我们将使用原生 YAML 在 Kubernetes 中安装 APISIX 和 APISIX Ingress 控制器。先决条件如果没有 Kubernetes 集群使用，建议使用 kind 创建本地 Kubernetes 集群。kubectl create ns apisix在本教程中，我们的所有操作都将在命名空间 apisix 中执行。ETCD 安装在这里，我们将在 Kubernetes 集群内部部署不带认证的单节点 ETCD 集群。在本例中，我们假设你拥有存储部署器。如果你正在使用 Kind，那么将自动创建本地路径部署器。如果没有存储部署器或不想使用持久化存储卷，那么可以使用 emptyDir 作为存储卷。# etcd-headless.yaml
apiVersion: v1
kind: Service
metadata:
name: etcd-headless
namespace: apisix
labels:
app.kubernetes.io/name: etcdannotations:
service.alpha.kubernetes.io/tolerate-unready-endpoints: "true"spec:
type: ClusterIP
clusterIP: None
ports:
- name: "client"
port: 2379
targetPort: client
- name: "peer"
port: 2380
targetPort: peerselector:
app.kubernetes.io/name: etcdetcd.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: etcd
namespace: apisix
labels:
app.kubernetes.io/name: etcdspec:
selector:
matchLabels:
app.kubernetes.io/name: etcdserviceName: etcd-headless
podManagementPolicy: Parallel
replicas: 1
updateStrategy:
type: RollingUpdatetemplate:
metadata:
labels:
app.kubernetes.io/name: etcd
spec:
securityContext:
fsGroup: 1001
runAsUser: 1001
containers:
- name: etcd
image: docker.io/bitnami/etcd:3.4.14-debian-10-r0
imagePullPolicy: "IfNotPresent"
# command:
# - /scripts/setup.sh
env:
- name: BITNAMI_DEBUG
value: "false"
- name: MY_POD_IP
valueFrom:
fieldRef:
fieldPath: status.podIP
- name: MY_POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: ETCDCTL_API
value: "3"
- name: ETCD_NAME
value: "$(MY_POD_NAME)"
- name: ETCD_DATA_DIR
value: /etcd/data
- name: ETCD_ADVERTISE_CLIENT_URLS
value: "http://$(MY_POD_NAME).etcd-headless.apisix.svc.cluster.local:2379"
- name: ETCD_LISTEN_CLIENT_URLS
value: "http://0.0.0.0:2379"
- name: ETCD_INITIAL_ADVERTISE_PEER_URLS
value: "http://$(MY_POD_NAME).etcd-headless.apisix.svc.cluster.local:2380"
- name: ETCD_LISTEN_PEER_URLS
value: "http://0.0.0.0:2380"
- name: ALLOW_NONE_AUTHENTICATION
value: "yes"
ports:
- name: client
containerPort: 2379
- name: peer
containerPort: 2380
volumeMounts:
- name: data
mountPath: /etcd
# If you don't have a storage provisioner or don't want to use persistence volume, you could use an `emptyDir` as follow.
# volumes:
# - name: data
# emptyDir: {}volumeClaimTemplates:
- metadata:
name: data
spec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "8Gi"请注意该 ETCD 安装非常简单，缺乏许多必要的生产特性，仅用于学习场景。如果想部署生产级 ETCD，请参阅 bitnami/etcd。APISIX 安装为我们的 APISIX 创建配置文件。我们将部署 2.5 版本的 APISIX。注意 APISIX Ingress 控制器需要与 APISIX 管理 API 进行通信，因此为进行测试，我们将 apisix.allow_admin 设置为 0.0.0.0/0。apiVersion: v1kind: ConfigMap
metadata:
name: apisix-conf
namespace: apisix
data:
config.yaml: |-
apisix:
node_listen: 9080 # APISIX listening port
enable_heartbeat: true
enable_admin: true
enable_admin_cors: true
enable_debug: false
enable_dev_mode: false # Sets nginx worker_processes to 1 if set to true
enable_reuseport: true # Enable nginx SO_REUSEPORT switch if set to true.
enable_ipv6: true
config_center: etcd # etcd: use etcd to store the config value
allow_admin: # Module ngx_http_access_module
- 0.0.0.0/0
port_admin: 9180
# Default token when use API to call for Admin API.
# *NOTE*: Highly recommended to modify this value to protect APISIX's Admin API.
# Disabling this configuration item means that the Admin API does not
# require any authentication.
admin_key:
# admin: can everything for configuration data
- name: "admin"
key: edd1c9f034335f136f87ad84b625c8f1
role: admin
# viewer: only can view configuration data
- name: "viewer"
key: 4054f7cf07e344346cd3f287985e76a2
role: viewer
# dns_resolver:
# - 127.0.0.1
dns_resolver_valid: 30
resolver_timeout: 5
nginx_config: # config for render the template to generate nginx.conf
error_log: "/dev/stderr"
error_log_level: "warn" # warn,error
worker_rlimit_nofile: 20480 # the number of files a worker process can open, should be larger than worker_connections
event:
worker_connections: 10620
http:
access_log: "/dev/stdout"
keepalive_timeout: 60s # timeout during which a keep-alive client connection will stay open on the server side.
client_header_timeout: 60s # timeout for reading client request header, then 408 (Request Time-out) error is returned to the client
client_body_timeout: 60s # timeout for reading client request body, then 408 (Request Time-out) error is returned to the client
send_timeout: 10s # timeout for transmitting a response to the client.then the connection is closed
underscores_in_headers: "on" # default enables the use of underscores in client request header fields
real_ip_header: "X-Real-IP" # Module ngx_http_realip_module
real_ip_from: # Module ngx_http_realip_module
- 127.0.0.1
- 'unix:'
etcd:
host:
- "http://etcd-headless.apisix.svc.cluster.local:2379"
prefix: "/apisix" # apisix configurations prefix
timeout: 30 # seconds
plugins: # plugin list
- api-breaker
- authz-keycloak
- basic-auth
- batch-requests
- consumer-restriction
- cors
- echo
- fault-injection
- grpc-transcode
- hmac-auth
- http-logger
- ip-restriction
- jwt-auth
- kafka-logger
- key-auth
- limit-conn
- limit-count
- limit-req
- node-status
- openid-connect
- prometheus
- proxy-cache
- proxy-mirror
- proxy-rewrite
- redirect
- referer-restriction
- request-id
- request-validation
- response-rewrite
- serverless-post-function
- serverless-pre-function
- sls-logger
- syslog
- tcp-logger
- udp-logger
- uri-blocker
- wolf-rbac
- zipkin
- traffic-split
stream_plugins:
- mqtt-proxy请确保 etcd.host 与我们最初创建的无头服务匹配。在我们的例子中，它是 http://etcd-headless.apisix.svc.cluster.local:2379。在该配置中，我们在 apisix.admin_key 部分的下方定义具有 admin 名称的访问密钥。该密钥是我们的 API 密钥，以后将用于控制 APISIX。该密钥是 APISIX 的默认密钥，在生产环境中，应该修改它。将其保存为 config.yaml，然后运行 kubectl -n apisix create -f config.yaml，创建 ConfigMap。稍后，我们将该 ConfigMap 挂载到 APISIX Deployment 中。apiVersion: apps/v1kind: Deployment
metadata:
name: apisix
namespace: apisix
labels:
app.kubernetes.io/name: apisixspec:
replicas: 1
selector:
matchLabels:
app.kubernetes.io/name: apisixtemplate:
metadata:
labels:
app.kubernetes.io/name: apisix
spec:
containers:
- name: apisix
image: "apache/apisix:2.5-alpine"
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 9080
protocol: TCP
- name: tls
containerPort: 9443
protocol: TCP
- name: admin
containerPort: 9180
protocol: TCP
readinessProbe:
failureThreshold: 6
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
tcpSocket:
port: 9080
timeoutSeconds: 1
lifecycle:
preStop:
exec:
command:
- /bin/sh
- -c
- "sleep 30"
volumeMounts:
- mountPath: /usr/local/apisix/conf/config.yaml
name: apisix-config
subPath: config.yaml
resources: {}
volumes:
- configMap:
name: apisix-conf
name: apisix-config现在，应该可以使用 APISIX 了。使用 kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name 来列举 APISIX Pod 名称。这里我们假设 Pod 名称是 apisix-7644966c4d-cl4k6。我们检查一下：kubectl -n apisix exec -it apisix-7644966c4d-cl4k6 -- curl http://127.0.0.1:9080如果你正在使用 Linux 或 macOS，那么在 Bash 中运行下面的命令：kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl http://127.0.0.1:9080如果 APISIX 正常工作，那么它应该输出：{"error_msg":"404 Route Not Found"}。因为我们尚未定义任何路由。HTTPBIN 服务在配置 APISIX 前，我们需要创建一个测试服务。在这里，我们使用 kennethreitz/httpbin。我们将该 httpbin 服务放在 demo 命名空间中。kubectl create ns demo
kubectl label namespace demo apisix.ingress=watching # 给 demo 命名空间添加 apisix.ingress 标签
kubectl -n demo run httpbin --image-pull-policy=IfNotPresent --image kennethreitz/httpbin --port 80
kubectl -n demo expose pod httpbin --port 80在 httpbin 服务启动后，我们应该可以在 APISIX Pod 中通过服务访问它。kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl http://httpbin.demo/get该命令输出请求的查询参数，比如：{ "args": {}, "headers": { "Accept": "*/*", "Host": "httpbin.demo", "User-Agent": "curl/7.67.0" }, "origin": "172.17.0.1", "url": "http://httpbin.demo/get" }如欲阅读更多，请参阅快速入门。定义路由现在，我们可以定义通过 APISIX 代理 HTTPBIN 服务流量的路由。假设我们想路由 URI 拥有 /httpbin 前缀，并且请求包含 Host: httpbin.org 头的所有流量。请注意管理端口是 9180。kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9180/apisix/admin/routes/1" -H "X-API-KEY: edd1c9f034335f136f87ad84b625c8f1" -X PUT -d '
{
"uri": "/*",
"host": "httpbin.org",
"upstream": {
"type": "roundrobin",
"nodes": {
"httpbin.demo:80": 1
}}
}'输出如下所示：{"action":"set","node":{"key":"/apisix/routes/1","value":{"status":1,"create_time":1621408897,"upstream":{"pass_host":"pass","type":"roundrobin","hash_on":"vars","nodes":{"httpbin.demo:80":1},"scheme":"http"},"update_time":1621408897,"priority":0,"host":"httpbin.org","id":"1","uri":"/"}}}我们可以通过 GET /apisix/admin/routes 检查路由规则：kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9180/apisix/admin/routes/1" -H "X-API-KEY: edd1c9f034335f136f87ad84b625c8f1"输出如下所示：{"action":"get","node":{"key":"\/apisix\/routes\/1","value":{"upstream":{"pass_host":"pass","type":"roundrobin","scheme":"http","hash_on":"vars","nodes":{"httpbin.demo:80":1}},"id":"1","create_time":1621408897,"update_time":1621408897,"host":"httpbin.org","priority":0,"status":1,"uri":"\/*"}},"count":"1"}现在，我们测试路由规则：kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9080/get" -H 'Host: httpbin.org'输出如下所示：{ "args": {}, "headers": { "Accept": "/*", "Host": "httpbin.org", "User-Agent": "curl/7.67.0", "X-Forwarded-Host": "httpbin.org" }, "origin": "127.0.0.1", "url": "http://httpbin.org/get" }安装 APISIX Ingress 控制器APISIX Ingress 控制器可以帮助你通过使用 Kubernetes 资源的方式，声明式地管理配置。这里我们将安装 1.6.0 版本。当前，APISIX Ingress 控制器同时支持官方的 Ingress 资源和 APISIX 的自定义资源定义，包括 ApisixRoute 和 ApisixUpstream。在安装 APISIX Ingress 控制器前，我们需要创建服务账号和相应的集群角色，以确保 APISIX Ingress 控制器有足够的权限访问所需的资源。下面是来自 apisix-helm-chart 的示例配置：
apiVersion: v1
kind: ServiceAccount
metadata:
name: apisix-ingress-controller
namespace: apisix
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: apisix-clusterrole
namespace: apisix
rules:
apiGroups:
- ""
resources:
- configmaps
- endpoints
- persistentvolumeclaims
- pods
- replicationcontrollers
- replicationcontrollers/scale
- serviceaccounts
- services
- secrets
verbs:
- get
- list
- watch
apiGroups:
- ""
resources:
- bindings
- events
- limitranges
- namespaces/status
- pods/log
- pods/status
- replicationcontrollers/status
- resourcequotas
- resourcequotas/status
verbs:
- get
- list
- watch
apiGroups:
- ""
resources:
- namespaces
verbs:
- get
- list
- watch
apiGroups:
- apps
resources:
- controllerrevisions
- daemonsets
- deployments
- deployments/scale
- replicasets
- replicasets/scale
- statefulsets
- statefulsets/scale
verbs:
- get
- list
- watch
apiGroups:
- autoscaling
resources:
- horizontalpodautoscalers
verbs:
- get
- list
- watch
apiGroups:
- batch
resources:
- cronjobs
- jobs
verbs:
- get
- list
- watch
apiGroups:
- extensions
resources:
- daemonsets
- deployments
- deployments/scale
- ingresses
- networkpolicies
- replicasets
- replicasets/scale
- replicationcontrollers/scale
verbs:
- get
- list
- watch
apiGroups:
- policy
resources:
- poddisruptionbudgets
verbs:
- get
- list
- watch
apiGroups:
- networking.k8s.io
resources:
- ingresses
- networkpolicies
verbs:
- get
- list
- watch
apiGroups:
- metrics.k8s.io
resources:
- pods
verbs:
- get
- list
- watch
apiGroups:
- apisix.apache.org
resources:
- apisixroutes
- apisixroutes/status
- apisixupstreams
- apisixupstreams/status
- apisixtlses
- apisixtlses/status
- apisixclusterconfigs
- apisixclusterconfigs/status
- apisixconsumers
- apisixconsumers/status
- apisixpluginconfigs
verbs:
- get
- list
- watch
apiGroups:
- coordination.k8s.io
resources:
- leases
verbs:
- '*'
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: apisix-clusterrolebinding
namespace: apisix
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: apisix-clusterrole
subjects:
- kind: ServiceAccount
name: apisix-ingress-controller
namespace: apisix然后，我们需要创建 ApisixRoute CRD：git clone https://github.com/apache/apisix-ingress-controller.git --depth 1
cd apisix-ingress-controller/
kubectl apply -k samples/deploy/crd请参阅 samples 获取细节。为使 Ingress 控制器与 APISIX 一起正常工作，我们需要创建一个配置文件，其中包含 APISIX 管理 API URL 和 API 密钥，如下所示：apiVersion: v1
data:
config.yaml: |
# log options
log_level: "debug"
log_output: "stderr"
http_listen: ":8080"
enable_profiling: true
kubernetes:
kubeconfig: ""
resync_interval: "30s"
namespace_selector:
- "apisix.ingress=watching"
ingress_class: "apisix"
ingress_version: "networking/v1"
apisix_route_version: "apisix.apache.org/v2"
apisix:
default_cluster_base_url: "http://apisix-admin.apisix:9180/apisix/admin"
default_cluster_admin_key: "edd1c9f034335f136f87ad84b625c8f1"kind: ConfigMap
metadata:
name: apisix-configmap
namespace: apisix
labels:
app.kubernetes.io/name: ingress-controller如果想学习所有配置项，查看 conf/config-default.yaml 获取细节。因为 Ingress 控制器需要访问 APISIX 管理 API，所以我们需要为 APISIX 创建一个服务。apiVersion: v1kind: Service
metadata:
name: apisix-admin
namespace: apisix
labels:
app.kubernetes.io/name: apisixspec:
type: ClusterIP
ports:
- name: apisix-admin
port: 9180
targetPort: 9180
protocol: TCP
selector:
app.kubernetes.io/name: apisix因为当前 APISIX Ingress 控制器不 100% 兼容 APISIX，所以我们需要删除之前创建的路由，以防某些数据结构不匹配。kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9180/apisix/admin/routes/1" -X DELETE -H "X-API-KEY: edd1c9f034335f136f87ad84b625c8f1"完成这些配置后，我们现在部署 Ingress 控制器。apiVersion: apps/v1
kind: Deployment
metadata:
name: apisix-ingress-controller
namespace: apisix
labels:
app.kubernetes.io/name: ingress-controllerspec:
replicas: 1
selector:
matchLabels:
app.kubernetes.io/name: ingress-controllertemplate:
metadata:
labels:
app.kubernetes.io/name: ingress-controller
spec:
serviceAccountName: apisix-ingress-controller
volumes:
- name: configuration
configMap:
name: apisix-configmap
items:
- key: config.yaml
path: config.yaml
initContainers:
- name: wait-apisix-admin
image: busybox:1.28
command: ['sh', '-c', "until nc -z apisix-admin.apisix.svc.cluster.local 9180 ; do echo waiting for apisix-admin; sleep 2; done;"]
containers:
- name: ingress-controller
command:
- /ingress-apisix/apisix-ingress-controller
- ingress
- --config-path
- /ingress-apisix/conf/config.yaml
image: "apache/apisix-ingress-controller:1.6.0"
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 8080
protocol: TCP
livenessProbe:
httpGet:
path: /healthz
port: 8080
readinessProbe:
httpGet:
path: /healthz
port: 8080
resources:
{}
volumeMounts:
- mountPath: /ingress-apisix/conf
name: configuration在该 Deployment 中，我们将上面创建的 ConfigMap 挂载为配置文件，并且告诉 Kubernetes 使用服务账号 apisix-ingress-controller。在 Ingress 控制器的状态转换为 Running 后，我们创建 APISIXRoute 资源，观察它的行为。下面是 APISIXRoute 示例：apiVersion: apisix.apache.org/v2
kind: ApisixRoute
metadata:
name: httpserver-route
namespace: demo
spec:
http:
name: httpbin
match:
hosts:- local.httpbin.org
paths: - /*
backends:
- serviceName: httpbin
servicePort: 80注意 apiVersion 字段应该匹配上面的 ConfigMap。serviceName 应该匹配暴露的服务名称，这里是 httpbin。在创建它前，我们确认带头 Host: local.http.demo 的请求返回 404：kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9080/get" -H 'Host: local.httpbin.org'将返回：{"error_msg":"404 Route Not Found"}在与目标服务相同的命名空间中应用 APISIXRoute，本例是 demo。在应用它后，我们检查它是否生效：kubectl -n apisix exec -it $(kubectl get pods -n apisix -l app.kubernetes.io/name=apisix -o name) -- curl "http://127.0.0.1:9080/get" -H "Host: local.httpbin.org"应该返回：{
"args": {},
"headers": {
"Accept": "/",
"Host": "local.httpbin.org",
"User-Agent": "curl/7.67.0",
"X-Forwarded-Host": "local.httpbin.org"
},
"origin": "127.0.0.1",
"url": "http://local2.httpbin.org/get"- local.httpbin.org
}
就是所有！享受你的 APISIX 和 APISIX Ingress 控制器之旅。Ingress 控制器用于 Kubernetes 的 Apache APISIX Ingress 控制器。模块
Ingress-types定义 Apache APISIX 所需的 CRD（CustomResourceDefinition）当前支持 ApisixRoute/ApisixUpstream，以及其它服务和路由级插件可打包为独立的二进制文件，与 Ingress 定义保持同步CRD 设计Types定义接口对象，以匹配 Apache APISIX 中的概念，比如路由、服务、上游和插件可打包为独立的二进制文件，需要匹配兼容的 Apache APISIX 版本向该模块添加新类型，以支持新特性Seven包含主应用程序逻辑基于 Apisix-types 对象，将 Kubernetes 集群状态同步到 Apache APISIXIngress-controllerIngress 控制器的驱动进程；监听 Kubernetes API Server在将控制移交给上面的模块 Seven 前，匹配并将 Apisix-ingress-types 转换为 Apisix-typesCRD 设计当前 apisix-ingress-controller CRD 包括 6 部分：ApisixRoute/ApisixUpstream/ApisixConsumer/ApisixTls/ApisixClusterConfig/ApisixPluginConfig。其设计遵循如下思想。网关最重要的部分是路由部分，它用于定义网关流量的分发规则为便于理解和配置，ApisixRoute 的设计结构与 Kubernetes Ingress 基本相似在注解的设计中，以 Kubernetes Ingress 的结构为参考，但内部实现基于 Apache APISIX 的插件在最简单的情况下，只需定义 ApisixRoute，Ingress 控制器将自动添加 ApisixUpstreamApisixUpstream 可以定义 Apache APISIX 上游上的一些细节，比如负载均衡/健康检查等监视 CRDapisix-ingress-controller 负责与 Kubernetes API Server 进行交互，申请可访问资源权限（RBAC），监视变更，在 Ingress 控制器中实现对象转换，比较变更，然后同步到 Apache APISIX。时序图
下面是介绍 ApisixRoute 和其它 CRD 在同步过程中的主要逻辑的流程图。
转换结构apisix-ingress-controller 为 CRD 提供外部配置方法。它针对的是日常运维等操作人员，他们经常需要批量地处理大量路由，希望在同一配置文件中处理所有相关服务，同时具有方便易懂的管理能力。而 Apache APISIX 从网关的角度进行设计，所有路由相互独立。这导致两者在数据结构上有明显的差异。一个侧重于批量定义，而另一个是离散实现。考虑到不同人群的使用习惯，CRD 的数据结构借鉴 Kubernetes Ingress 的数据结构，在形态上基本相同。简单的对比如下，它们有不同的定义：
他们是多对多的关系。因此，apisix-ingress-controller 必须对 CRD 执行一些转换，以适配不同网关。级联更新目前，我们定义多个 CRD，这些 CRD 负责它们各自的字段定义。ApisixRoute/ ApisixUpstream 对应 Apache APISIX 中的 route/ service/upstream 等对象。由于 APISIX 对象之间的强绑定关系，在批量修改和删除 CRD 等数据结构时，必须考虑对象之间的级联影响。因此，在 apisix-ingress-controller 中，通过 channel 实现广播通知机制，即任何对象的定义必须被通知给与其相关的其它对象，并且触发相应的行为。
差分规则seven 模块在内部保存内存数据结构，目前它与 Apache APISIX 资源对象非常相似。当 Kubernetes 资源对象发生新变更时，seven 将比较内存对象，然后根据比较结果，进行增量更新。当前的比较规则基于 route / service / upstream 资源对象的分组，分别进行比较，发现差异后，进行相应的广播通知。
服务发现apisix-ingress-controller 根据 ApisixUpstream 资源对象中定义的 namespace、name、port，将处于 running 状态的 endpoints 节点信息注册到 Apache APISIX Upstream 中的节点。并且根据 Kubernetes，实时同步 Endpoint 状态。基于服务发现，Apache APISIX Ingress 可以直接访问后端 Pod 节点。绕过 Kubernetes 服务，可实现定制化的负载均衡策略。注解实现与 Kubernetes Nginx Ingress 的实现不同，apisix-ingress-controller 基于 Apache APISIX 的插件机制实现注解。比如，通过 ApisixRoute 资源对象中的 k8s.apisix.apache.org/whitelist-source-range 注解配置黑/白名单设置。apiVersion: apisix.apache.org/v2
kind: ApisixRoute
metadata:
annotations:
k8s.apisix.apache.org/whitelist-source-range: 1.2.3.4,2.2.0.0/16name: httpserver-route
spec:
...这里的黑/白名单由 ip-restriction 插件实现。未来将有更多注释实现，以方便定义一些常见配置，比如 CORS。如果你有注解需求，欢迎到 issue 讨论，我们讨论如何进行实现。参考文档https://apisix.apache.org/zh/docs/ingress-controller/tutorials/the-hard-way/https://apisix.apache.org/zh/do