Kubernetes YAML Validator

Lint your K8s manifests for missing fields and best-practice issues.

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Input
Output
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About kubernetes yaml validator

Kubernetes YAML Validator keeps its state in memory and nowhere else. That is why it forgets everything on reload, and why it cannot leak anything.

Once the page has loaded it needs nothing further from the network. Work on a plane, on a train, or behind a firewall that blocks everything.

You will find it under Containers & deploys, alongside 7 other tools for the same sort of job.

Checks apiVersion, kind, metadata, labels, resource limits, health probes, security context, and image tags.

How to use it

01
Start it
Every control is on the tool itself. Keyboard shortcuts, where there are any, are listed beside it.
02
Watch it run
It updates in the page as you go. Nothing is sent anywhere, so it keeps working with the network off.
03
Close when done
Nothing is stored between visits. Reloading gives you a clean start rather than picking up where you left off.

Examples

Deployment missing probes + resource limits
Validate a Deployment that uses :latest tag and lacks labels, resource limits, and health probes
Input
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
spec:
  template:
    spec:
      containers:
        - name: web
          image: nginx:latest
Output
# Kubernetes Manifest Validation

Kind: Deployment
Errors: 0 | Warnings: 5

## Warnings
  - Line 10: Avoid using ':latest' image tag
  - No labels defined - labels are recommended for organization
  - No resource requests/limits defined - recommended for production
  - No livenessProbe defined - recommended for reliability
  - No readinessProbe defined - recommended for zero-downtime deploys

## Info
  - No namespace specified - will use 'default'
  - No securityContext defined - consider adding for security hardening

Manifest structure is valid!

Questions

Does Kubernetes YAML Validator work offline?+

Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.

Does it remember anything between visits?+

No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.

Is it accurate?+

Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.

Does it make a sound?+

Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.

Can I use Kubernetes YAML Validator on a phone?+

Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.