k8s_pod_shell.sh

#!/bin/bash

# Load variables
DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
source "$DIR/variables.sh"

# Read pod name into variable (allowed only valid pod names)
read_pod_name() {
    while read -p "Open shell for pod name: " POD_NAME </dev/tty
    do
        if [[ ! " ${POD_NAMES[@]} " =~ " ${POD_NAME} " ]]; then
            echo "Error: Pod name not found or invalid!"
        else
            break
        fi
    done
}

# Read namespace into variable
read_namespace() {
    # I have namespace from script argument
    if [[ ! -z "$1" ]]; then
        NAMESPACE="$1"

        return
    fi

    while read -p "Namespace: " NAMESPACE </dev/tty
    do
        if [[ ! "$NAMESPACE" =~ ^[0-9]+$ ]]; then
            echo "Error: Namespace must contain only numbers!"
        else
            break
        fi
    done
}

read_namespace "$1"

echo "================================================================="
az account set --subscription="$SUBSCRIPTION_ID"
az aks get-credentials --name "$CLUSTER_NAME" --resource-group "$RESOURCE_GROUP" --overwrite >> /dev/null 2>&1
kubectl get pods -n "$NAMESPACE"

POD_NAMES=($(kubectl get pods -n "$NAMESPACE" | awk 'NR>1 {print $1}'))

# Check if there are any pods in this namespace
if [[ "${#POD_NAMES[@]}" -eq 0 ]]; then
    echo "Not found any pods - terminating!"
    exit 101
fi

echo "================================================================="
read_pod_name

# Open shell for specified pod
kubectl exec -it -n "$NAMESPACE" "$POD_NAME" -- "/bin/sh"