Log Kubernetes pod

log-pod.sh

#!/bin/bash
#
# Saves logs for all containers in a pod.
#
set -o nounset -o errexit -o pipefail

# Function to print the usage
usage() {
  echo "Usage: $0 [-n namespace] <pod-name>"
  exit 1
}

# Default namespace is empty
NAMESPACE_ARG=""
NAMESPACE_DISPLAY=""

# Parse the arguments
while getopts ":n:" opt; do
  case $opt in
    n)
      NAMESPACE_ARG="--namespace $OPTARG"
      NAMESPACE_DISPLAY="in namespace $OPTARG "
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      usage
      ;;
    :)
      echo "Option -$OPTARG requires an argument." >&2
      usage
      ;;
  esac
done
shift $((OPTIND -1))

# Check if a pod name was passed as an argument
if [ -z "${1-}" ]; then
  echo "Error: No pod name provided."
  usage
fi

# Assign the remaining argument to a variable
POD_NAME=$1

# Function to check if the pod is ready
is_pod_ready() {
  STATUS=$(kubectl get pod $POD_NAME $NAMESPACE_ARG -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}')
  if [ "$STATUS" == "True" ]; then
    return 0
  else
    return 1
  fi
}

# Wait until the pod is ready
while ! is_pod_ready; do
  echo "Pod $POD_NAME is not ready yet. Checking again in 5 seconds..."
  sleep 5
done

LOG_DIR="$HOME/scratch/log/$POD_NAME"
mkdir -p "$LOG_DIR"

kubectl get pod $POD_NAME $NAMESPACE_ARG -o yaml > $LOG_DIR/$POD_NAME.yaml
kubectl describe pod $POD_NAME $NAMESPACE_ARG > $LOG_DIR/$POD_NAME-describe.txt

LOG_FILE="$LOG_DIR/$POD_NAME.log"
echo "Logging from all container in pod $POD_NAME ${NAMESPACE_DISPLAY}to $LOG_FILE"

# Logs from all containers in a pod, prefixing each log line with the timestamp and the container name. Saves the log to a file.
kubectl logs -f $POD_NAME $NAMESPACE_ARG --all-containers=true --prefix=true --timestamps=true | tee $LOG_FILE