Kubernetes for Developers
Joseph Heck更新时间：2021-08-27 19:04:55
最新章节：Leave a review - let other readers know what you think封面
Title Page
Copyright and Credits
Kubernetes for Developers
Packt Upsell
Why subscribe?
PacktPub.com
Contributors
About the author
About the reviewers
Packt is searching for authors like you
Preface
Who this book is for
What this book covers
To get the most out of this book
Download the example code files
Conventions used
Get in touch
Reviews
Setting Up Kubernetes for Development
What you need for development
Optional tools
Getting a local cluster up and running
Resetting and restarting your cluster
Looking at what's built-in and included with Minikube
Verifying Docker
Clearing and cleaning Docker images
Kubernetes concept – container
Kubernetes resource – Pod
Namespaces
Writing your code for Pods and Containers
Kubernetes resource – Node
Networks
Controllers
Kubernetes resource – ReplicaSet
Kubernetes resource – Deployment
Representing Kubernetes resources
Summary
Packaging Your Code to Run in Kubernetes
Container images
Container registries
Making your first container
Dockerfile commands
Example – Python/Flask container image
Building the container
Running your container
Pod name
Port forwarding
Proxy
How did the proxy know to connect to port 5000 on the container?
Getting logs from your application
Example – Node.js/Express container image
Building the container
Running your container
Port forwarding
Proxy
Getting logs from your application
Tagging your container images
Summary
Interacting with Your Code in Kubernetes
Practical notes for writing software to run in a container
Getting options for your executable code
Practical notes for building container images
Sending output from your program
Logs
Pods with more than one container
Streaming the logs
Previous logs
Timestamps
More debugging techniques
Interactive deployment of an image
Attaching to a running Pod
Running a second process in a container
Kubernetes concepts – labels
Organization of labels
Kubernetes concepts – selectors
Viewing labels
Listing resources with labels using kubectl
Automatic labels and selectors
Kubernetes resources – service
Defining a service resource
Endpoints
Service type – ExternalName
Headless service
Discovering services from within your Pod
DNS for services
Exposing services outside the cluster
Service type – LoadBalancer
Service type – NodePort
Minikube service
Example service – Redis
Finding the Redis service
Using Redis from Python
Updating the Flask deployment
Deployments and rollouts
Rollout history
Rollout undo
Updating with the kubectl set command
Summary
Declarative Infrastructure
Imperative versus declarative commands
A wall of YAML
Creating a simple deployment
Declaring your first application
ImagePullPolicy
Audit trail
Kubernetes resource – Annotations
Exposing labels and annotations in Pods
Kubernetes resource – ConfigMap
Creating a ConfigMap
Managing ConfigMaps
Exposing the configuration into your container images
Environment variables
Exposing ConfigMap as files inside the container
Dependencies on ConfigMaps
Kubernetes resource – Secrets
Exposing Secrets into a container
Secrets and security – how secret are the secrets?
Example – Python/Flask deployment with ConfigMap
SIDEBAR – JSONPATH
Using the ConfigMap within Python/Flask
Summary
Pod and Container Lifecycles
Pod lifecycle
Container lifecycle
Deployments ReplicaSets and Pods
Getting a snapshot of the current state
Probes
Liveness probe
Readiness probe
Adding a probe to our Python example
Running the Python probes example
Adding a probe to our Node.js example
Container lifecycle hooks
Initialization containers
Quick interactive testing
Handling a graceful shutdown
SIGTERM in Python
SIGTERM in Node.js
Summary
Background Processing in Kubernetes
Job
CronJob
A worker queue example with Python and Celery
Celery worker example
RabbitMQ and configuration
Celery worker
Persistence with Kubernetes
Volumes
PersistentVolume and PersistentVolumeClaim
Stateful Sets
A Node.js example using Stateful Set
Custom Resource Definition
Summary
Monitoring and Metrics
Built-in metrics with Kubernetes
Kubernetes concept – Quality of Service
Choosing requests and limits for your containers
Capturing metrics with Prometheus
Installing Helm
Installing Prometheus using Helm
Viewing metrics with Prometheus
Installing Grafana
Using Prometheus to view application metrics
Flask metrics with Prometheus
Node.js metrics with Prometheus
Service signals in Prometheus
Summary
Logging and Tracing
A Kubernetes concept – DaemonSet
Installing and using Elasticsearch Fluentd and Kibana
Log aggregation with EFK
Viewing logs using Kibana
Filtering by app
Lucene query language
Running Kibana in production
Distributed tracing with Jaeger
Spans and traces
Architecture of Jaeger distributed tracing
Trying out Jaeger
Example – adding tracing to your application
Adding a tracing collector to your pod
Add the libraries and code to generate traces
Considerations for adding tracing
Summary
Integration Testing
Testing strategies using Kubernetes
Reviewing resources needed for testing
Patterns of using Kubernetes with testing
Tests local and system-under-test in Kubernetes
Tests local and system-under-test in Kubernetes namespaces
Tests in Kubernetes and system-under-test in Kubernetes namespaces
Simple validation with Bats
Example – integration testing with Python
PyTest and pytest-dependency
PyTest fixtures and the python-kubernetes client
Waiting for state changes
Accessing the deployment
Example – integration testing with Node.js
Node.js tests and dependencies with mocha and chai
Validating the cluster health
Deploying with kubectl
Waiting for the pods to become available
Interacting with the deployment
Continuous integration with Kubernetes
Example – using Minikube with Travis.CI
Next steps
Example – using Jenkins and the Kubernetes plugin
Installing Jenkins using Helm
Accessing Jenkins
Updating Jenkins
Example pipeline
Next steps with pipelines
Summary
Troubleshooting Common Problems and Next Steps
Common errors and how to resolve them
Error validating data
Navigating the documentation
ErrImagePull
CrashLoopBackOff
Starting and inspecting the image
Adding your own setup to the container
No endpoints available for service
Stuck in PodInitializing
Missing resources
Emerging projects for developers
Linters
Helm
ksonnet
Brigade
skaffold
img
Draft
ksync
Telepresence
Interacting with the Kubernetes project
Slack
YouTube
Stack Overflow
Mailing lists and forums
Summary
Other Books You May Enjoy
Leave a review - let other readers know what you think
更新时间：2021-08-27 19:04:55