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Introduction

In this part of the course, we will set up your local development environment so that you are ready to handle the challenges of the story. This will consist of two steps:

  1. Loading your computers state (aka, getting the source code)
  2. Booting up the ship's computer core (aka, running the source code)

Loading your computers state

Since your ship's computer runs on good old Git, the easiest way to get your computer source code into Visual Studio Code is to just clone the Git repository.

You will be navigating in the terminal by using the cd command, which stands for change directory.

To do that, let's start by opening a terminal. Once you've got that open, navigate to the directory where you want to copy the source code folder into by using

cd path/to/your/code/folder

where path/to/your/code/folder is the path to a folder of your choosing. Having all your code in one root folder is recommended, and keep in mind that git clone will create a new folder within your chosen folder. You can also use

cd ..

to change back to the parent directory. Finally, if you want to create a new folder, you can use

mkdir folderName

mkdir is a unix command that stands for make directory.

Once you are where you want to be, you can start the code download by executing

git clone https://github.com/EliasRut/distant-stars.git

which will pull the latest version of the master branch into a newly created distant-stars folder. Now all you need to do is to navigate into that new folder, and open your code editor. Of course you will use the one and only code editor that is fully endorsed and recommended by Space Academy, Visual Studio Code. You can do this by executing the following in your terminal

cd distant-stars
code .

code is the command to open Visual Studio Code from your terminal, and the . will set the open working directory to be the directory you are currently in.

Booting up your systems

To see the current state of your ship's computer system, you can use the start script defined in the repositories package.json file. This script uses the node command to start up the mainframe and run the system diagnostics test, and reads as follows

  "scripts": {
    "start": "node src/coreSystems/mainframe.js && node src/coreSystems/systemControlIntegration.js"
  },

To run this script, we can make use of the node package manager, that knows about everything happening in the package.json file. Node package manager, or npm for short, is a set of tools for dealing with JavaScript projects, from handling dependencies to setting up new projects and running node scripts. The npm run scriptName command can be used to start any scripts defined in the scripts section of your package.json file.

Let's get started by running

npm run start

This should produce an output similar to this one

                     `. ___
                    __,' __`.                _..----....____
        __...--.'``;.   ,.   ;``--..__     .'    ,-._    _.-'
  _..-''-------'   `'   `'   `'     O ``-''._   (,;') _,'
,'________________                          \`-._`-','
 `._              ```````````------...___   '-.._'-:
    ```--.._      ,.                     ````--...__\-.
            `.--. `-`                       ____    |  |`
              `. `.                       ,'`````.  ;  ;`
                `._`.        __________   `.      \'__/`
                   `-:._____/______/___/____`.     \  `
                               |       `._    `.    \
                               `._________`-.   `.   `.___
                                                  `------'`
Starting mainframe....
-> Mainframe systems loaded.
Loading system control software...


System control software loaded.
Running system diagnostics...

===========================================================
  Main system check
===========================================================
  Main computer systems...................... online
  Bridge control systems..................... offline
  Life support............................... offline
  Main Reactor............................... offline
  Thrusters.................................. offline
  Navigation systems......................... offline
  Scanners................................... offline
  Deflector shields.......................... offline
  Targeting systems.......................... offline

===========================================================
  Starting failed subsytem trace
  Tracing bridge control systems
===========================================================
  Critical system access..................... denied
  Telemetry data............................. missing
  Ship clocks................................ inconsistent


Ship systems shutting down

Understanding the system output

This code base is setup in such a way that, assuming only typical erros, you should always at least get to the line stating

Loading system control software...

If you produced an error that stops node from even running your code, you will now see an error message followed by what is called a stack trace, listing where your error is. Something like this

Starting mainframe....
-> Mainframe systems loaded.
Loading system control software...


path/to/your/code/folder/src/lifeSupport.js:16
}
^

SyntaxError: Unexpected end of input
    at Module._compile (internal/modules/cjs/loader.js:721:23)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)
    at Module.require (internal/modules/cjs/loader.js:690:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at Object.<anonymous> (/path/to/your/code/folder/src/coreSystems/systemControlIntegration.js:2:85)
    at Module._compile (internal/modules/cjs/loader.js:776:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! space-ranger@1.0.0 start: `node src/coreSystems/mainframe.js && node src/coreSystems/systemControlIntegration.js`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the space-ranger@1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm WARN Local package.json exists, but node_modules missing, did you mean to install?

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/yourUser/.npm/_logs/2020-09-09T20_51_58_806Z-debug.log

If there is no error, you will see the line 

System control software loaded.

followed by a list of main system checks, one for each of the lessons that make up this course - and you get

  Main computer systems...................... online

just for finishing this introduction lesson.

Finally, you'll get a list of subsystems that represent individual tasks of the current unfinished lesson. Assuming you have not solved any tasks yet, you will see

===========================================================
  Starting failed subsytem trace
  Tracing bridge control systems
===========================================================
  Critical system access..................... denied
  Telemetry data............................. missing
  Ship clocks................................ inconsistent

telling you that the bridge control chapter is the next one that is unfinished, and that the three tasks in it are currently failing.

Next steps

This is the end of the introduction lesson. The next one will be your first step into writing code, and deals with value types, the basics of functions and the return statement.