bash redis queue

redis_queue.sh

# START - QUEUE

# Function: _queue_command
# Description: Adds a command to the Redis command queue with an optional schedule.
# Parameters:
#   $1: The command to be added to the queue. Example "echo Hello, World!"
#   $2: (Optional) The schedule for the command ("2023-06-30 12:00:00"). Default is "now".
# Returns: None

_queue_command() {
    local command="$1"
    local schedule="${2:-now}"
    local timestamp

    if [[ "$schedule" == "now" ]]; then
        timestamp=$(date "+%Y-%m-%d_%H-%M-%S")
    else
        timestamp=$(date -d "$schedule" "+%Y-%m-%d_%H-%M-%S")
    fi

    redis-cli rpush command_queue "$timestamp:$command"
}

# Function: _process_queue
# Description: Starts a queue worker that processes commands from the Redis queue.
# Parameters: None
# Returns: None

_process_queue() {
    local lock_key="worker_lock"
    local lock_value="1"

    # Get public IP
    local public_ip lock_status commands count timestamp cmd current_time output
    public_ip=$(_get_public_ip)

    while true; do
        # Acquire the lock
        lock_status=$(redis-cli setnx $lock_key $lock_value)

        # If lock is acquired, process the commands
        if [[ $lock_status -eq 1 ]]; then
            mapfile -t commands < <(redis-cli lrange command_queue 0 -1)
            count=${#commands[@]}

            if [[ $count -gt 0 ]]; then
                echo "Executing $count command(s)"

                for command in "${commands[@]}"; do
                    timestamp=${command%%:*}
                    cmd=${command#*:}
                    current_time=$(date "+%Y-%m-%d_%H-%M-%S")

                    if [[ "$timestamp" == "$current_time" || "$timestamp" == "now" ]]; then
                        echo "Executing command: $cmd"
                        output=$(eval "$cmd")  # Execute the command and capture the output

                        if [[ $? -ne 0 ]]; then
                            echo "Command execution failed. Logging error..."
                            echo "$output" > error.txt
                            curl -X POST -H "Content-Type: text/plain" -d @error.txt "${DEPLOYMENT_ERROR_URL}/${public_ip}"
                        fi

                        redis-cli lrem command_queue 1 "$command"
                    fi
                done
            fi

            # Release the lock
            redis-cli del $lock_key
        else
            sleep 1s
        fi
    done
}
# END - QUEUE