【发布时间】：2021-03-26 11:01:35
【问题描述】：
到目前为止，我使用 docker 和 docker-compose 在本地开发 Python 应用程序。现在我想更改我的开发工作流程，使用skaffold 和docker 作为构建器，使用kubectl 作为部署器，使用minikube 管理本地kubernetes 集群。
假设我有这个用于 FastAPI 的基于 docker 的 hello world：
项目结构：
app/app.py
Dockerfile
app/app.py
from typing import Optional
from fastapi import FastAPI
app = FastAPI()
@app.get("/")
def read_root():
return {"Hello": "World"}
@app.get("/items/{item_id}")
def read_item(item_id: int, q: Optional[str] = None):
return {"item_id": item_id, "q": q}
Dockerfile：
FROM tiangolo/uvicorn-gunicorn-fastapi:python3.7
COPY ./app /app
如果我运行docker build -t hello-fastapi . 和docker run -p 80:80 hello-fastapi，我可以通过0.0.0.0 或localhost 访问该服务。我在这里跳过docker-compose 的事情，因为这并不重要。脚手架设置。
要使用skaffold，我有完全相同的项目结构和内容，但我添加了 skaffold + kubectl 特定的东西（skaffold.yaml，deployment.yaml）：
项目结构：
app/app.py
k8s/deployment.yaml
Dockerfile
skaffold.yaml
k8s/deployment.yaml
apiVersion: v1
kind: Service
metadata:
name: fastapi-service
labels:
app: fastapi-service
spec:
clusterIP: None
ports:
- port: 80
name: fastapi-service
selector:
app: fastapi-service
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: fastapi-service
labels:
app: fastapi-service
spec:
replicas: 1
selector:
matchLabels:
app: fastapi-service
template:
metadata:
labels:
app: fastapi-service
spec:
containers:
- name: fastapi-service
image: fastapi-service
ports:
- containerPort: 80
skaffold.yaml
apiVersion: skaffold/v2beta10
kind: Config
build:
artifacts:
- image: fastapi-image
deploy:
kubectl:
manifests:
- k8s/*
如果我运行 skaffold dev 一切似乎都很好：
Listing files to watch...
- fastapi-service
Generating tags...
- fastapi-service -> fastapi-service:latest
Some taggers failed. Rerun with -vdebug for errors.
Checking cache...
- fastapi-service: Found Locally
Tags used in deployment:
- fastapi-service -> fastapi-service:17659a877904d862184d7cc5966596d46b0765f1995f7abc958db4b3f98b8a35
Starting deploy...
- service/fastapi-service created
- deployment.apps/fastapi-service created
Waiting for deployments to stabilize...
- deployment/fastapi-service is ready.
Deployments stabilized in 2.165700782s
Press Ctrl+C to exit
Watching for changes...
[fastapi-service] Checking for script in /app/prestart.sh
[fastapi-service] Running script /app/prestart.sh
[fastapi-service] Running inside /app/prestart.sh, you could add migrations to this file, e.g.:
[fastapi-service]
[fastapi-service] #! /usr/bin/env bash
[fastapi-service]
[fastapi-service] # Let the DB start
[fastapi-service] sleep 10;
[fastapi-service] # Run migrations
[fastapi-service] alembic upgrade head
[fastapi-service]
[fastapi-service] [2020-12-15 19:02:57 +0000] [1] [INFO] Starting gunicorn 20.0.4
[fastapi-service] [2020-12-15 19:02:57 +0000] [1] [INFO] Listening at: http://0.0.0.0:80 (1)
[fastapi-service] [2020-12-15 19:02:57 +0000] [1] [INFO] Using worker: uvicorn.workers.UvicornWorker
[fastapi-service] [2020-12-15 19:02:57 +0000] [8] [INFO] Booting worker with pid: 8
...
但是我无法通过我的网络浏览器访问该服务。如何通过例如从本地计算机访问服务网络浏览器？
编辑：
根据minikube service list服务fastapi-service存在：
|----------------------|---------------------------|--------------|-----|
| NAMESPACE | NAME | TARGET PORT | URL |
|----------------------|---------------------------|--------------|-----|
| default | fastapi-service | No node port |
| default | kubernetes | No node port |
| kube-system | kube-dns | No node port |
| kubernetes-dashboard | dashboard-metrics-scraper | No node port |
| kubernetes-dashboard | kubernetes-dashboard | No node port |
|----------------------|---------------------------|--------------|-----|
但我无法通过curl $(minikube service fastapi-service --url)访问它：
curl: (3) Failed to convert ???? to ACE; string contains a disallowed character
curl: (6) Could not resolve host: service
curl: (6) Could not resolve host: default
curl: (6) Could not resolve host: has
curl: (6) Could not resolve host: no
curl: (6) Could not resolve host: node
curl: (6) Could not resolve host: port
这可能与 Unable to get ClusterIP service url from minikube 有关。如果我将deployment.yaml 更改为
apiVersion: v1
kind: Service
metadata:
name: fastapi-service
labels:
app: fastapi-service
spec:
type: NodePort
ports:
- targetPort: 80
port: 80
selector:
app: fastapi-service
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: fastapi-service
labels:
app: fastapi-service
spec:
replicas: 1
selector:
matchLabels:
app: fastapi-service
template:
metadata:
labels:
app: fastapi-service
spec:
containers:
- name: fastapi-service
image: fastapi-service
ports:
- containerPort: 80
通过curl $(minikube service fastapi-service --url)访问服务成功：
{"message":"Hello world! From FastAPI running on Uvicorn with Gunicorn. Using Python 3.7"}
但是我无法通过网络浏览器访问该服务。
【问题讨论】：
标签： python kubernetes fastapi skaffold