nicholaskajoh

#!/bin/bash

# Get SSL cert from Let's Encrypt.
# See https://www.digitalocean.com/community/tutorials/how-to-create-let-s-encrypt-wildcard-certificates-with-certbot.
certbot certonly \
    --server https://acme-v02.api.letsencrypt.org/directory \
    --dns-digitalocean \
    --dns-digitalocean-credentials /path/to/certbot-creds.ini \
    --dns-digitalocean-propagation-seconds 300 \
    -d \*.example.com \

nicholaskajoh

nicholas@Inspiron-3542:~/dev/SANDBOX/knex$ npm ls -prod
knex@0.21.1 /home/nicholas/dev/SANDBOX/knex
├── colorette@1.1.0
├── commander@5.1.0
├─┬ debug@4.1.1
│ └── ms@2.1.2
├── esm@3.2.25
├── getopts@2.2.5
├── inherits@2.0.4
├── interpret@2.0.0

nicholaskajoh

function up(knex) {
    return knex.schema.table('random', (table) => {
        table.boolean('is_deleted')
            .defaultsTo(0)
            .notNullable();
    });
}

function down(knex) {
    const tableName = 'random';

nicholaskajoh

# Refresh repos
sudo apt update
# Update system
sudo apt upgrade

# Install Python 2
sudo apt install python2.7 python-pip

# Install Python 3
sudo apt install software-properties-common

nicholaskajoh

# Source ROS env
source /opt/ros/melodic/setup.bash

# Create package (in path/to/workspace/src)
# NB: std_msgs and rospy are dependencies
# catkin_create_pkg my_package std_msgs rospy

# Create scripts directory in package root
# mkdir scripts

nicholaskajoh

• Install ROS: http://wiki.ros.org/Installation/Ubuntu
• Create Catkin workspace: http://wiki.ros.org/catkin/Tutorials/create_a_workspace
• Change directory to workspace root and run setup script: source devel/setup.bash (test printenv | grep ROS; expect ROS env vars to be set)
• Create a package: http://wiki.ros.org/ROS/Tutorials/CreatingPackage

nicholaskajoh

Array.prototype.customMap = function(fn) {
  if (typeof fn !== 'function') throw Error('Am I a joke to you?');

  const arr = this;
  const arrLen = arr.length;

  const getNewArr = (index, newArr) => {
    if (index < arrLen) {
      const newItem = fn(arr[index], index, arr);
      return getNewArr(index + 1, [...newArr, newItem]);

nicholaskajoh

# 1. Download latest release and unzip
# https://github.com/carla-simulator/carla/releases/latest

# 2. Start CARLA server
./CarlaUE4.sh -opengl -fps=30 -quality-level=Low -windowed -ResX=1000 -ResY=600
# To use different map,
# Change directory to PythonAPI/util
# Then run:
# python config.py -m Town05
# Change weather:

nicholaskajoh

# Setup
# 1. Install Docker for your OS
# 2. Pull Docker image for Elasticsearch: docker pull docker.elastic.co/elasticsearch/elasticsearch:7.3.0
# 3. Pull Docker image for Kibana: docker pull docker.elastic.co/kibana/kibana:7.3.0
# 4. Run this script: chmod +x elk.sh && ./elk.sh

# Test
# Elasticsearch: curl http://127.0.0.1:9200/_cat/health
# Kibana: visit http://localhost:5601

nicholaskajoh

# 1. Enable SSH on your Raspberry Pi (https://www.raspberrypi.org/documentation/remote-access/ssh/).
# 2. Plug Pi to PC using an ethernet cable and enable the ethernet device in your settings.
# 3. Use the ifconfig command to get the ethernet device name and IP address e.g enx00e04c534458 and fe80::666c:c924:194c:1756 respectively.
# 4. SSH into Pi with default user (pi) and password (raspberry).
ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no -Y -6 pi@fe80::666c:c924:194c:1756%enx00e04c534458