kubectl create configmap

The sources for creating a ConfigMap can be combined: literal values, single files, all files in a folder, and env files. A file's key name can be changed with key=file:

kubectl create configmap web-ayar \
  --from-literal=TEMA=koyu \
  --from-file=nginx.conf \
  --from-file=index=site/index.html \
  --from-file=ayarlar/            # each file in the folder is a key

kubectl create errors on an existing object. The clean way to update a ConfigMap produced from files: regenerate the YAML and apply it. Then the deployment is restarted for pods reading the change as environment variables:

kubectl create configmap web-ayar --from-file=nginx.conf --dry-run=client -o yaml | kubectl apply -f -
kubectl rollout restart deployment/web

ConfigMaps written with immutable: true can't be changed; in big clusters this reduces the API server's load.