Table of Contents

Kubernetes Cheat Sheet:
Extract `ConfigMap` or `Secret` to .env file
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Extract from `ConfigMap`
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kubectl get configmap my-map --output json | jq '.data' | jq -r 'to_entries | map(.key + "=" + (.value)) | .[]' >> .env

Explanation:

kubectl get configmap my-map --output json |
    # Extract the data section.
    jq '.data' |
    # Replace each "key": "value" pair with "key=value"
    jq -r 'to_entries | map(.key + "=" + (.value)) | .[]' >> .env

Extract from `Secret`
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kubectl get secret my-secret --output json | jq '.data' | jq 'map_values(@base64d)' | jq -r 'to_entries | map(.key + "=" + (.value)) | .[]' >> .env

Explanation:

kubectl get secret my-secret --output json |
    # Extract the data section.
    jq '.data' |
    # Decode the value of each keys.
    jq 'map_values(@base64d)' |
    # Replace each "key": "value" pair with "key=value"
    jq -r 'to_entries | map(.key + "=" + (.value)) | .[]' >> .env

Extract from `helm`
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# Extract the values with a `awk` script: we print everything starting from the line that contains only `configmap` until the first empty line.
awk '{if ($0 ~ /^configmap:$/) {triggered=1;}if (triggered) {print; if ($0 ~ /^$/) { exit;}}}' "./project/values.yaml" |
    # Keep only the indented lines that contains our configuration values.
    grep '^  ' |
    # Transform key: value into key=value
    sed 's/  //;s/: /=/' >> .env