Monitor kubevirt live migration progress in the terminal

kubevirt-monitor-live-migration.sh

#!/usr/bin/env bash

# usage
# kubevirt-monitor-live-migration.sh my-namespace/my-vm
#

namespace_vm=${1?vm name}
vm=${namespace_vm##*/}
namespace=${namespace_vm%%/*}

bar_size=40
bar_char_done="#"
bar_char_todo="-"
bar_percentage_scale=2

#export KUBECONFIG=/tmp/kubeconfig

function show_progress {
    current="$1"
    total="$2"

    # calculate the progress in percentage 
    percent=$(bc <<< "scale=$bar_percentage_scale; 100 * $current / $total" )
    # The number of done and todo characters
    done=$(bc <<< "scale=0; $bar_size * $percent / 100" )
    todo=$(bc <<< "scale=0; $bar_size - $done" )

    # build the done and todo sub-bars
    done_sub_bar=$(printf "%${done}s" | tr " " "${bar_char_done}")
    todo_sub_bar=$(printf "%${todo}s" | tr " " "${bar_char_todo}")

    # output the bar
    echo -ne "\rProgress : [${done_sub_bar}${todo_sub_bar}] ${percent}%"

    if [[ ${total} -eq ${current} ]]; then
        echo -e "\nDONE"
    fi
}

lastDataProcessed=0

# Read events from stdin
#oc logs -f -n "${namespace}" -l "vm.kubevirt.io/name=${vm},!kubevirt.io/migrationJobUID" \
oc logs -f -n "${namespace}" -l "vm.kubevirt.io/name=${vm}" \
    | while read -r event; do

    # Reset values
    TimeElapsed=0
    DataProcessed=0
    # DataRemaining=''
    DataTotal=0
    MemoryProcessed=0
    MemoryRemaining=0
    MemoryTotal=0
    # MemoryBandwidth=''
    # DirtyRate=''
    # Iteration=''
    # PostcopyRequests=''
    # ConstantPages=''
    # NormalPages=''
    # NormalData=''
    # ExpectedDowntime=''
    # DiskMbps=''

    message=$(echo "${event}" | jq -r .msg)

    if [[ ${message} != "Migration info for"* ]] ; then
        # echo noop
        continue
    fi

    stats=$(echo "${message}" | sed -E 's/Migration info for [a-f0-9-]+: //' | sed -e 's/ /\n/g' -e 's/:/=/g')

    eval "${stats}"

    # Clean the data
    DataProcessed="${DataProcessed%MiB}"
    DataTotal=${DataTotal%MiB}
    TimeElapsed=${TimeElapsed%ms}
    MemoryProcessed=${MemoryProcessed%MiB}
    MemoryRemaining=${MemoryRemaining%MiB}
    MemoryTotal=${MemoryTotal%MiB}
    
    diffDataProcessed=$((DataProcessed - lastDataProcessed))
    diffTimeElapsed=$(bc <<< "scale=$bar_percentage_scale; (${TimeElapsed} - ${lastTimeElapsed}) / 1000")
    lastDataProcessed=${DataProcessed%MiB}
    lastTimeElapsed=${TimeElapsed}


    mps=$(bc <<< "scale=$bar_percentage_scale; $diffDataProcessed/$diffTimeElapsed")
    echo " rate $mps MiB/sec"

    # # Draw the progress bar
    # show_progress "${DataProcessed}" "${DataTotal}"
    show_progress "$((MemoryTotal - MemoryRemaining))" "${MemoryTotal}"

done

# Add a new line after the progress bar is complete
echo