基础设施即代码
学习基础设施即代码如何以声明式方式定义云资源，从而实现可重复、可版本控制的自动化配置。
基础设施即代码 是 CoddyKit 上的免费 System Design Basics for Backend Developers 课时。 这是第 4 节课，共 4 节。 你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。 这是 System Design Basics for Backend Developers 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 System Design Basics for Backend Developers 课程共包含 4 节课。
本课时的部分内容尚未翻译，以英文显示。
From Clicking to Code
Manually clicking through a cloud console to create servers and networks is slow, error-prone, and impossible to reproduce. Infrastructure as Code (IaC) defines your infrastructure in files you can version, review, and re-run.
Why IaC Matters
IaC brings software engineering discipline to infrastructure:
- Version control and code review for changes
- Reproducible environments (dev, staging, prod identical)
- Automated, fast provisioning and teardown
- Self-documenting infrastructure
Declarative vs Imperative
IaC tools are usually declarative: you describe the desired end state and the tool figures out how to get there. Imperative scripts instead list the exact steps. Declarative is easier to reason about and converge to.
A Declarative Resource
Here is a declarative definition of a virtual machine. You state what should exist; the tool creates or updates it to match.
resource "aws_instance" "web" {
ami = "ami-123456"
instance_type = "t3.micro"
tags = {
Name = "web-server"
}
}Idempotency
A core IaC property is idempotency: applying the same definition repeatedly yields the same result. If the resource already matches, nothing changes. This makes re-runs safe.
State and Drift
Many tools track a state of what they manage. When reality diverges — someone changes a resource by hand — that is drift. The tool detects drift and can reconcile infrastructure back to the declared definition.
Plan Before Apply
Good IaC workflows preview changes before applying them. A plan step shows exactly what will be created, changed, or destroyed, so you catch a destructive change in review rather than in production.
$ terraform plan
+ aws_instance.web will be created
~ aws_security_group.sg will be updated
- aws_instance.old will be destroyedProvisioning vs Configuration
Two related but distinct jobs:
- Provisioning creates infrastructure (Terraform, CloudFormation, Pulumi)
- Configuration management sets up software on existing machines (Ansible, Chef, Puppet)
Containers and immutable images blur this line.
Modules and Reuse
Avoid copy-paste by packaging infrastructure into reusable modules with input variables. One well-tested module can stamp out identical, parameterized environments for many teams.
module "web" {
source = "./modules/app"
instance_type = "t3.small"
env = "production"
}IaC and Cloud-Native CI/CD
IaC fits naturally into pipelines: a commit triggers a plan, review approves it, and the pipeline applies it. Combined with containers and Kubernetes manifests, the entire stack — network, cluster, and apps — becomes reproducible from code.
Best Practices
Keep IaC healthy: store state remotely and locked, never hardcode secrets, review every plan, keep modules small, and treat infrastructure code exactly like application code — tested and reviewed.
Quick Check
Test your understanding of Infrastructure as Code.
Recap
You learned the foundations of Infrastructure as Code:
- Declarative definitions describe desired state idempotently
- State tracking detects and reconciles drift
- Plan before apply to preview changes safely
- Modules enable reuse; IaC integrates into CI/CD pipelines
常见问题解答
「基础设施即代码」课时是免费的吗？
是的 — 「基础设施即代码」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 System Design Basics for Backend Developers 课程的其余内容，请升级到 CoddyKit PRO。 System Design Basics for Backend Developers 课程共包含 4 节课。
「基础设施即代码」这节课中我会学到什么？
学习基础设施即代码如何以声明式方式定义云资源，从而实现可重复、可版本控制的自动化配置。 你通过在浏览器中直接运行的动手代码来练习 System Design Basics for Backend Developers，全天候 AI 导师会在你学习这节课的过程中回答你的问题。
学习 System Design Basics for Backend Developers 需要有经验吗？
无需任何先前经验。CoddyKit 上的 System Design Basics for Backend Developers 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。 这是第 4 节课，共 4 节。
「基础设施即代码」课时需要多长时间？
大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。
我能在这节 System Design Basics for Backend Developers 课中编写并运行代码吗？
能。每节 System Design Basics for Backend Developers 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。