Which command is used to create a ConfigMap in Kubernetes from a file containing key-value entries?

Which command is used to create a ConfigMap in Kubernetes from a file containing key-value entries?

• A. kubectl create configmap colour-configmap --from-literal=COLOUR=red
• B. kubectl apply -f configmap.yaml
• C. kubectl create configmap colour-configmap --from-env-file=configmap-colour.properties
• D. kubectl get configmap

Answer: (C)

Creating a ConfigMap from a file that contains key-value entries is done by reading an environment-style file where each line is KEY=VALUE and turning those lines into data entries in the ConfigMap. The option that loads such a file and names the ConfigMap accordingly is used with the file path, so each line in the file becomes one key-value pair in the ConfigMap. This matches the requirement of creating from a file containing key-value entries. The other approaches don’t fit: one creates a ConfigMap from a literal key-value inline, not from a file; another applies a manifest from disk rather than constructing the ConfigMap from a key-value file; and the last retrieves an existing ConfigMap rather than creating a new one.

Creating a ConfigMap from a file that contains key-value entries is done by reading an environment-style file where each line is KEY=VALUE and turning those lines into data entries in the ConfigMap. The option that loads such a file and names the ConfigMap accordingly is used with the file path, so each line in the file becomes one key-value pair in the ConfigMap. This matches the requirement of creating from a file containing key-value entries.

The other approaches don’t fit: one creates a ConfigMap from a literal key-value inline, not from a file; another applies a manifest from disk rather than constructing the ConfigMap from a key-value file; and the last retrieves an existing ConfigMap rather than creating a new one.