./swarm-change-log-level.sh -d <swarm_ip> -p <admin:password> -i <new_log_level> [-t <duration_in_seconds>] [--background] [-v]

./swarm-change-log-level.sh -d 192.168.8.84 -p admin:datacore -i 20 -t 10

./swarm-change-log-level.sh -d 192.168.8.84 -p admin:datacore -i 20 -t 30 --background -v

[root@scs dist]# ./swarm-change-log-level.sh -p admin:datacore -i 20 -t 300
Swarm IP: 192.168.1.84
Credentials: [hidden for security]
Cluster Name: gatewayadmindomain

New log level: 5
Current log level is 30.
Updating log level to 5...
Log level changed successfully from 30 → 5.
Keeping log level at 5 for 300 second(s)...
Countdown: 00:00:01 remaining...

Time's up! Reverting log level back to 30...
Approximate 69.4MB new logs were generated at log level 5. Current castor.log size is 371.3MB after 00:05:00.
Log level reverted successfully back to 30.

[root@scs dist]#

#!/bin/bash
# Written by Milton Suen (milton.suen@datacore.com) Oct 31, 2024
# Revision: Update to support running the script in a background session using screen or tmux.

# Function to display usage information
usage() {
    echo "Usage: $0 -d swarm_ip -p admin:password -i new_log_level [-t duration_in_seconds] [--background] [-v]"
    echo "  -d, --swarm_ip           IP address of the Swarm API endpoint (or set SCSP_HOST environment variable)"
    echo "  -p, --credentials        Credentials in the format admin:password"
    echo "  -i, --log.level          New log level to set"
    echo "  -t, --time               Duration in seconds to keep the new log level (optional)"
    echo "  --background             Run the script in a detached session using screen or tmux"
    echo "  -v, --verbose            Enable verbose mode for debug messages"
    exit 1
}

# Default options
background=false
verbose=false
output_log="script_output.log"  # Log file for capturing background session output

# Function to display debug messages if verbose mode is enabled
debug() {
    if $verbose; then
        echo "[DEBUG] $1"
    fi
}

# Function to check if either 'screen' or 'tmux' is installed
check_screen_or_tmux() {
    if ! command -v screen &>/dev/null && ! command -v tmux &>/dev/null; then
        echo "Error: Neither 'screen' nor 'tmux' is installed. Cannot run in background mode."
        background=false  # Disable background session
    fi
}

# Function to format file size
format_size() {
    local size=$1
    if (( size >= 1073741824 )); then
        echo "$(awk "BEGIN {printf \"%.1fGB\", $size/1073741824}")"
    elif (( size >= 1048576 )); then
        echo "$(awk "BEGIN {printf \"%.1fMB\", $size/1048576}")"
    elif (( size >= 1024 )); then
        echo "$(awk "BEGIN {printf \"%.1fKB\", $size/1024}")"
    else
        echo "${size}B"
    fi
}

# Function to format duration
format_duration() {
    local duration=$1
    local hours=$((duration / 3600))
    local minutes=$(( (duration % 3600) / 60 ))
    local seconds=$((duration % 60))
    printf "%02d:%02d:%02d" $hours $minutes $seconds
}

# Function to check if jq is available and set up JSON parsing method
check_jq() {
    if [[ -x "/usr/local/bin/jq" ]]; then
        echo "/usr/local/bin/jq"
    elif [[ -x "$(pwd)/jq" ]]; then
        echo "$(pwd)/jq"
    elif command -v jq &>/dev/null; then
        echo "jq"
    else
        echo "grep"
    fi
}

jq_or_grep=$(check_jq)

# Parse input arguments
while [[ "$#" -gt 0 ]]; do
    case $1 in
        -d|--swarm_ip) swarm_ip="$2"; shift 2 ;;
        -p|--credentials) credentials="$2"; shift 2 ;;
        -i|--log.level) new_log_level="$2"; shift 2 ;;
        -t|--time)
            if [[ -n "$2" && "$2" != -* ]]; then
                duration="$2"
                shift 2
            else
                read -p "Enter duration in seconds: " duration
                shift
            fi
            ;;
        --background) background=true; shift ;;
        -v|--verbose) verbose=true; shift ;;
        *) usage ;;
    esac
done

# Check if 'screen' or 'tmux' is installed
check_screen_or_tmux

# If swarm_ip is not provided, try using SCSP_HOST environment variable
if [[ -z "$swarm_ip" ]]; then
    if [[ -n "$SCSP_HOST" ]]; then
        swarm_ip="$SCSP_HOST"
        debug "Using Swarm IP from SCSP_HOST: $swarm_ip"
    else
        echo "Error: swarm_ip not provided and SCSP_HOST is not set."
        usage
    fi
fi

# Check if required arguments are provided
if [[ -z "$credentials" || -z "$new_log_level" ]]; then
    usage
fi

# Retrieve cluster name and handle JSON parsing
debug "Retrieving the cluster name from Swarm API."
if [[ "$jq_or_grep" == "grep" ]]; then
    clusterName=$(curl --user "$credentials" -sS "http://$swarm_ip:91/api/storage/clusters" | grep -oP '"name":\s*"\K[^"]+')
else
    clusterName=$(curl --user "$credentials" -sS "http://$swarm_ip:91/api/storage/clusters" | "$jq_or_grep" -r '._embedded.clusters[0].name')
fi

if [[ -z "$clusterName" ]]; then
    echo "Failed to retrieve the cluster name. Please check your inputs."
    exit 1
fi
debug "Cluster Name: $clusterName"

# Main logic function to run the script tasks
main_script() {
    local swarm_ip="$1"
    local credentials="$2"
    local new_log_level="$3"
    local duration="$4"
    local clusterName="$5"
    local log_file="/var/log/datacore/castor.log"
    local initial_size=$(stat -c%s "$log_file" 2>/dev/null || echo 0)
    local current_log_level
    local jq_or_grep="$6"

    # Display initial information
    echo "Swarm IP: $swarm_ip"
    echo "Credentials: [hidden for security]"
    echo "Cluster Name: $clusterName"

    debug "Starting main_script function..."

    # Retrieve current log level
    if [[ "$jq_or_grep" == "grep" ]]; then
        current_log_level=$(curl --user "$credentials" -sS "http://$swarm_ip:91/api/storage/clusters/$clusterName/settings/log.level" | grep -oP '"value":\s*\K[0-9]+')
    else
        current_log_level=$(curl --user "$credentials" -sS "http://$swarm_ip:91/api/storage/clusters/$clusterName/settings/log.level" | "$jq_or_grep" -r '.value')
    fi
    echo ""
    echo "New log level: $new_log_level"
    echo "Current log level is $current_log_level."

    # Skip update if new level matches the current level
    if [[ "$current_log_level" -eq "$new_log_level" ]]; then
        echo ""
        echo "Log level is already set to $new_log_level. No changes made."
        return
    fi

    # Update the log level using PUT
    echo "Updating log level to $new_log_level..."
    response=$(curl --user "$credentials" -sS -X PUT -H "Content-Type: application/json" \
        "http://$swarm_ip:91/api/storage/clusters/$clusterName/settings/log.level" \
        -d "{\"value\": $new_log_level}")

    if [[ "$jq_or_grep" == "grep" ]]; then
        updated_log_level=$(echo "$response" | grep -oP '"value":\s*\K[0-9]+')
    else
        updated_log_level=$(echo "$response" | "$jq_or_grep" -r '.value')
    fi

    if [[ "$updated_log_level" -eq "$new_log_level" ]]; then
        echo "Log level changed successfully from $current_log_level → $new_log_level."
    else
        echo "Failed to update log level. Response: $response"
        exit 1
    fi

    # Countdown and revert log level
    if [[ -n "$duration" && "$duration" -gt 0 ]]; then
        echo "Keeping log level at $new_log_level for $duration second(s)..."
        for ((i=duration; i>0; i--)); do
            printf -v countdown "%02d:%02d:%02d" $((i/3600)) $(( (i%3600) / 60 )) $((i%60))
            echo -ne "Countdown: $countdown remaining...\r"
            sleep 1
        done
        echo -e "\n\nTime's up! Reverting log level back to $current_log_level..."

        response=$(curl --user "$credentials" -sS -X PUT -H "Content-Type: application/json" \
            "http://$swarm_ip:91/api/storage/clusters/$clusterName/settings/log.level" \
            -d "{\"value\": $current_log_level}")

        if [[ "$jq_or_grep" == "grep" ]]; then
            reverted_log_level=$(echo "$response" | grep -oP '"value":\s*\K[0-9]+')
        else
            reverted_log_level=$(echo "$response" | "$jq_or_grep" -r '.value')
        fi

        final_size=$(stat -c%s "$log_file" 2>/dev/null || echo 0)
        size_diff=$(( final_size - initial_size ))
        size_diff_formatted=$(format_size "$size_diff")
        duration_formatted=$(format_duration "$duration")
        echo "Approximate $size_diff_formatted new logs were generated at log level $new_log_level. Current castor.log size is $(format_size "$final_size") after $duration_formatted."

        if [[ "$reverted_log_level" -eq "$current_log_level" ]]; then
            echo "Log level reverted successfully back to $current_log_level."
        else
            echo "Failed to revert log level. Response: $response"
            exit 1
        fi
    else
        echo "Log level change is permanent until manually modified."
    fi
}

# Run in background or directly
if $background; then
    # Pass the main_script function to the screen session and store the output in a file
    if command -v screen &>/dev/null; then
        screen -dmS indexer_script bash -c "$(declare -f main_script format_size format_duration check_jq debug); main_script \"$swarm_ip\" \"$credentials\" \"$new_log_level\" \"$duration\" \"$clusterName\" \"$jq_or_grep\" | tee \"$output_log\""
        screen -r indexer_script
    elif command -v tmux &>/dev/null; then
        tmux new-session -d -s indexer_script "$(declare -f main_script format_size format_duration check_jq debug); main_script \"$swarm_ip\" \"$credentials\" \"$new_log_level\" \"$duration\" \"$clusterName\" \"$jq_or_grep\" | tee \"$output_log\""
        tmux attach-session -t indexer_script
    else
        echo "Error: Neither screen nor tmux available. Run without --background."
        exit 1
    fi

    # Wait for the screen session to complete and then display the output log
    sleep 1
    while screen -list | grep -q "indexer_script"; do
        sleep 1
    done

    echo ""
    cat "$output_log"
else
    main_script "$swarm_ip" "$credentials" "$new_log_level" "$duration" "$clusterName" "$jq_or_grep" | tee "$output_log"
fi