无法从 Postman 的 k8s-Skaffold 中获得 Express API 的响应
Can't get response from Express API in k8s-Skaffold from Postman
尝试做一些应该非常简单的事情：启动一个 Express pod 并获取 localhost:5000/，它应该以 Hello World!.
响应
- 我已经为 Docker for Mac and minikube 安装了
ingress-nginx
- 强制:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/mandatory.yaml
- Docker 对于 Mac:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/provider/cloud-generic.yaml
- minikube:
minikube addons enable ingress
- 我运行
skaffold dev --tail
- 它打印出
Example app listening on port 5000，所以显然是 运行ning
- 导航到
localhost 和 localhost:5000 并得到 "Could not get any response" 错误
- 此外，尝试了
minikube ip，即 192.168.99.100，结果相同
不太确定我在这里做错了什么。代码和配置如下。建议？
index.js
// Import dependencies
const express = require('express');
// Set the ExpressJS application
const app = express();
// Set the listening port
// Web front-end is running on port 3000
const port = 5000;
// Set root route
app.get('/', (req, res) => res.send('Hello World!'));
// Listen on the port
app.listen(port, () => console.log(`Example app listening on port ${port}`));
skaffold.yaml
apiVersion: skaffold/v1beta15
kind: Config
build:
local:
push: false
artifacts:
- image: sockpuppet/server
context: server
docker:
dockerfile: Dockerfile.dev
sync:
manual:
- src: '**/*.js'
dest: .
deploy:
kubectl:
manifests:
- k8s/ingress-service.yaml
- k8s/server-deployment.yaml
- k8s/server-cluster-ip-service.yaml
入口-service.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: ingress-service
annotations:
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/rewrite-target: /
spec:
rules:
- http:
paths:
- path: /?(.*)
backend:
serviceName: server-cluster-ip-service
servicePort: 5000
服务器-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: server-deployment
spec:
replicas: 3
selector:
matchLabels:
component: server
template:
metadata:
labels:
component: server
spec:
containers:
- name: server
image: sockpuppet/server
ports:
- containerPort: 5000
server-cluster-ip-service.yaml
apiVersion: v1
kind: Service
metadata:
name: server-cluster-ip-service
spec:
type: ClusterIP
selector:
component: server
ports:
- port: 5000
targetPort: 5000
Dockerfile.dev
FROM node:12.10-alpine
EXPOSE 5000
WORKDIR "/app"
COPY ./package.json ./
RUN npm install
COPY . .
CMD ["npm", "run", "dev"]
来自describe
的输出
$ kubectl describe ingress ingress-service
Name: ingress-service
Namespace: default
Address:
Default backend: default-http-backend:80 (<none>)
Rules:
Host Path Backends
---- ---- --------
localhost
/ server-cluster-ip-service:5000 (172.17.0.7:5000,172.17.0.8:5000,172.17.0.9:5000)
Annotations:
kubectl.kubernetes.io/last-applied-configuration: {"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"annotations":{"kubernetes.io/ingress.class":"nginx"},"name":"ingress-service","namespace":"default"},"spec":{"rules":[{"host":"localhost","http":{"paths":[{"backend":{"serviceName":"server-cluster-ip-service","servicePort":5000},"path":"/"}]}}]}}
kubernetes.io/ingress.class: nginx
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal CREATE 16h nginx-ingress-controller Ingress default/ingress-service
Normal CREATE 21s nginx-ingress-controller Ingress default/ingress-service
来自kubectl get po -l component=server
的输出
$ kubectl get po -l component=server
NAME READY STATUS RESTARTS AGE
server-deployment-cf6dd5744-2rnh9 1/1 Running 0 11s
server-deployment-cf6dd5744-j9qvn 1/1 Running 0 11s
server-deployment-cf6dd5744-nz4nj 1/1 Running 0 11s
kubectl describe pods server-deployment 的输出：注意到 Host Port: 0/TCP。可能是问题？
Name: server-deployment-6b78885779-zttns
Namespace: default
Priority: 0
PriorityClassName: <none>
Node: minikube/10.0.2.15
Start Time: Tue, 08 Oct 2019 19:54:03 -0700
Labels: app.kubernetes.io/managed-by=skaffold-v0.39.0
component=server
pod-template-hash=6b78885779
skaffold.dev/builder=local
skaffold.dev/cleanup=true
skaffold.dev/deployer=kubectl
skaffold.dev/docker-api-version=1.39
skaffold.dev/run-id=c545df44-a37d-4746-822d-392f42817108
skaffold.dev/tag-policy=git-commit
skaffold.dev/tail=true
Annotations: <none>
Status: Running
IP: 172.17.0.5
Controlled By: ReplicaSet/server-deployment-6b78885779
Containers:
server:
Container ID: docker://2d0aba8f5f9c51a81f01acc767e863b7321658f0a3d0839745adb99eb0e3907a
Image: sockpuppet/server:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7
Image ID: docker://sha256:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7
Port: 5000/TCP
Host Port: 0/TCP
State: Running
Started: Tue, 08 Oct 2019 19:54:05 -0700
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-qz5kr (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
default-token-qz5kr:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-qz5kr
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled <unknown> default-scheduler Successfully assigned default/server-deployment-6b78885779-zttns to minikube
Normal Pulled 7s kubelet, minikube Container image "sockpuppet/server:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7" already present on machine
Normal Created 7s kubelet, minikube Created container server
Normal Started 6s kubelet, minikube Started container server
好的，现在解决了这个问题。
它归结为正在使用的服务类型：ClusterIP。
ClusterIP: Exposes the service on a cluster-internal IP. Choosing this value makes the service only reachable from within the cluster. This is the default ServiceType.
如果我想直接从集群外部（例如 Postman、pgAdmin 等）连接到 Pod 或 Deployment 和 我想使用服务，我应该使用 NodePort:
NodePort: Exposes the service on each Node’s IP at a static port (the NodePort). A ClusterIP service, to which the NodePort service will route, is automatically created. You’ll be able to contact the NodePort service, from outside the cluster, by requesting <NodeIP>:<NodePort>.
所以在我的例子中，如果我想继续使用服务，我会将我的服务清单更改为：
apiVersion: v1
kind: Service
metadata:
name: server-cluster-ip-service
spec:
type: NodePort
selector:
component: server
ports:
- port: 5000
targetPort: 5000
nodePort: 31515
确保手动设置 nodePort: <port> 否则它有点随机并且使用起来很痛苦。
然后我将使用 minikube ip 获取 minikube IP 并使用 192.168.99.100:31515 连接到 Pod。
那时，一切都按预期进行。
但这意味着有单独的开发集 (NodePort) 和生产集 (ClusterIP) 清单，这可能完全没问题。但我希望我的清单尽可能接近生产版本（即 ClusterIP）。
有几种方法可以解决这个问题：
- 使用 Kustomize 之类的东西，您可以在其中设置 base.yaml，然后为每个环境覆盖，它只是更改相关信息，避免大部分重复的清单。
使用 kubectl port-forward。我想这就是我要走的路。这样我就可以保留我的一套生产清单，但是当我想用 pgAdmin 对 Postgres 进行 QA 时，我可以这样做：
kubectl port-forward services/postgres-cluster-ip-service 5432:5432
或者对于后端和 Postman：
kubectl port-forward services/server-cluster-ip-service 5000:5000
我正在尝试使用 nginx-ingress 通过 ingress-service.yaml 执行此操作，但还没有完成。当我这样做时会更新。但对我来说，port-forward 似乎是可行的方法，因为我可以只拥有一套无需更改的生产清单。
Skaffold 端口转发
这更符合我的需要。将其附加到 skaffold.yaml 的底部，与 kubectl port-forward 基本相同，无需占用一两个终端：
portForward:
- resourceType: service
resourceName: server-cluster-ip-service
port: 5000
localPort: 5000
- resourceType: service
resourceName: postgres-cluster-ip-service
port: 5432
localPort: 5432
然后 运行 skaffold dev --port-forward.
尝试做一些应该非常简单的事情：启动一个 Express pod 并获取 localhost:5000/，它应该以 Hello World!.
- 我已经为 Docker for Mac and minikube 安装了
ingress-nginx- 强制:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/mandatory.yaml - Docker 对于 Mac:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/provider/cloud-generic.yaml - minikube:
minikube addons enable ingress
- 强制:
- 我运行
skaffold dev --tail - 它打印出
Example app listening on port 5000，所以显然是 运行ning - 导航到
localhost和localhost:5000并得到 "Could not get any response" 错误 - 此外，尝试了
minikube ip，即192.168.99.100，结果相同
不太确定我在这里做错了什么。代码和配置如下。建议？
index.js
// Import dependencies
const express = require('express');
// Set the ExpressJS application
const app = express();
// Set the listening port
// Web front-end is running on port 3000
const port = 5000;
// Set root route
app.get('/', (req, res) => res.send('Hello World!'));
// Listen on the port
app.listen(port, () => console.log(`Example app listening on port ${port}`));
skaffold.yaml
apiVersion: skaffold/v1beta15
kind: Config
build:
local:
push: false
artifacts:
- image: sockpuppet/server
context: server
docker:
dockerfile: Dockerfile.dev
sync:
manual:
- src: '**/*.js'
dest: .
deploy:
kubectl:
manifests:
- k8s/ingress-service.yaml
- k8s/server-deployment.yaml
- k8s/server-cluster-ip-service.yaml
入口-service.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: ingress-service
annotations:
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/rewrite-target: /
spec:
rules:
- http:
paths:
- path: /?(.*)
backend:
serviceName: server-cluster-ip-service
servicePort: 5000
服务器-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: server-deployment
spec:
replicas: 3
selector:
matchLabels:
component: server
template:
metadata:
labels:
component: server
spec:
containers:
- name: server
image: sockpuppet/server
ports:
- containerPort: 5000
server-cluster-ip-service.yaml
apiVersion: v1
kind: Service
metadata:
name: server-cluster-ip-service
spec:
type: ClusterIP
selector:
component: server
ports:
- port: 5000
targetPort: 5000
Dockerfile.dev
FROM node:12.10-alpine
EXPOSE 5000
WORKDIR "/app"
COPY ./package.json ./
RUN npm install
COPY . .
CMD ["npm", "run", "dev"]
来自describe
$ kubectl describe ingress ingress-service
Name: ingress-service
Namespace: default
Address:
Default backend: default-http-backend:80 (<none>)
Rules:
Host Path Backends
---- ---- --------
localhost
/ server-cluster-ip-service:5000 (172.17.0.7:5000,172.17.0.8:5000,172.17.0.9:5000)
Annotations:
kubectl.kubernetes.io/last-applied-configuration: {"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"annotations":{"kubernetes.io/ingress.class":"nginx"},"name":"ingress-service","namespace":"default"},"spec":{"rules":[{"host":"localhost","http":{"paths":[{"backend":{"serviceName":"server-cluster-ip-service","servicePort":5000},"path":"/"}]}}]}}
kubernetes.io/ingress.class: nginx
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal CREATE 16h nginx-ingress-controller Ingress default/ingress-service
Normal CREATE 21s nginx-ingress-controller Ingress default/ingress-service
来自kubectl get po -l component=server
$ kubectl get po -l component=server
NAME READY STATUS RESTARTS AGE
server-deployment-cf6dd5744-2rnh9 1/1 Running 0 11s
server-deployment-cf6dd5744-j9qvn 1/1 Running 0 11s
server-deployment-cf6dd5744-nz4nj 1/1 Running 0 11s
kubectl describe pods server-deployment 的输出：注意到 Host Port: 0/TCP。可能是问题？
Name: server-deployment-6b78885779-zttns
Namespace: default
Priority: 0
PriorityClassName: <none>
Node: minikube/10.0.2.15
Start Time: Tue, 08 Oct 2019 19:54:03 -0700
Labels: app.kubernetes.io/managed-by=skaffold-v0.39.0
component=server
pod-template-hash=6b78885779
skaffold.dev/builder=local
skaffold.dev/cleanup=true
skaffold.dev/deployer=kubectl
skaffold.dev/docker-api-version=1.39
skaffold.dev/run-id=c545df44-a37d-4746-822d-392f42817108
skaffold.dev/tag-policy=git-commit
skaffold.dev/tail=true
Annotations: <none>
Status: Running
IP: 172.17.0.5
Controlled By: ReplicaSet/server-deployment-6b78885779
Containers:
server:
Container ID: docker://2d0aba8f5f9c51a81f01acc767e863b7321658f0a3d0839745adb99eb0e3907a
Image: sockpuppet/server:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7
Image ID: docker://sha256:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7
Port: 5000/TCP
Host Port: 0/TCP
State: Running
Started: Tue, 08 Oct 2019 19:54:05 -0700
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-qz5kr (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
default-token-qz5kr:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-qz5kr
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled <unknown> default-scheduler Successfully assigned default/server-deployment-6b78885779-zttns to minikube
Normal Pulled 7s kubelet, minikube Container image "sockpuppet/server:668dfe550d93a0ae76eb07e0bab900f3968a7776f4f177c97f61b18a8b1677a7" already present on machine
Normal Created 7s kubelet, minikube Created container server
Normal Started 6s kubelet, minikube Started container server
好的，现在解决了这个问题。
它归结为正在使用的服务类型：ClusterIP。
ClusterIP: Exposes the service on a cluster-internal IP. Choosing this value makes the service only reachable from within the cluster. This is the default ServiceType.
如果我想直接从集群外部（例如 Postman、pgAdmin 等）连接到 Pod 或 Deployment 和 我想使用服务，我应该使用 NodePort:
NodePort: Exposes the service on each Node’s IP at a static port (the NodePort). A ClusterIP service, to which the NodePort service will route, is automatically created. You’ll be able to contact the NodePort service, from outside the cluster, by requesting
<NodeIP>:<NodePort>.
所以在我的例子中，如果我想继续使用服务，我会将我的服务清单更改为：
apiVersion: v1
kind: Service
metadata:
name: server-cluster-ip-service
spec:
type: NodePort
selector:
component: server
ports:
- port: 5000
targetPort: 5000
nodePort: 31515
确保手动设置 nodePort: <port> 否则它有点随机并且使用起来很痛苦。
然后我将使用 minikube ip 获取 minikube IP 并使用 192.168.99.100:31515 连接到 Pod。
那时，一切都按预期进行。
但这意味着有单独的开发集 (NodePort) 和生产集 (ClusterIP) 清单，这可能完全没问题。但我希望我的清单尽可能接近生产版本（即 ClusterIP）。
有几种方法可以解决这个问题：
- 使用 Kustomize 之类的东西，您可以在其中设置 base.yaml，然后为每个环境覆盖，它只是更改相关信息，避免大部分重复的清单。
使用
kubectl port-forward。我想这就是我要走的路。这样我就可以保留我的一套生产清单，但是当我想用 pgAdmin 对 Postgres 进行 QA 时，我可以这样做：kubectl port-forward services/postgres-cluster-ip-service 5432:5432或者对于后端和 Postman：
kubectl port-forward services/server-cluster-ip-service 5000:5000
我正在尝试使用 nginx-ingress 通过 ingress-service.yaml 执行此操作，但还没有完成。当我这样做时会更新。但对我来说，port-forward 似乎是可行的方法，因为我可以只拥有一套无需更改的生产清单。
Skaffold 端口转发
这更符合我的需要。将其附加到 skaffold.yaml 的底部，与 kubectl port-forward 基本相同，无需占用一两个终端：
portForward:
- resourceType: service
resourceName: server-cluster-ip-service
port: 5000
localPort: 5000
- resourceType: service
resourceName: postgres-cluster-ip-service
port: 5432
localPort: 5432
然后 运行 skaffold dev --port-forward.