mirror of
https://github.com/bitburner-official/bitburner-src.git
synced 2024-11-19 22:23:51 +01:00
181 lines
7.2 KiB
ReStructuredText
181 lines
7.2 KiB
ReStructuredText
.. _netscriptjs:
|
|
|
|
NetscriptJS (Netscript 2.0)
|
|
===========================
|
|
Netscript 2.0, or Netscript JS, is the new and improved version of Netscript that
|
|
allows users to write (almost) full-fledged Javascript code in their scripts, while
|
|
still being able to access the Netscript functions.
|
|
|
|
NetscriptJS was developed primarily by `Github user jaguilar <https://github.com/jaguilar>`_
|
|
|
|
On top of having almost all of the features and capabilities of JavaScript, NetscriptJS is also
|
|
significantly faster than Netscript 1.0.
|
|
|
|
This documentation will not go over any of the additional features of NetscriptJS, since
|
|
there is plenty of documentation on Javascript available on the web.
|
|
|
|
Browser compatibility
|
|
---------------------
|
|
As of the time of writing this, a few browsers do not support `dynamic import <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import>`_ functionality and therefore cannot run NetscriptJS scripts. These browsers will thus only be capable of using Netscript 1.0.
|
|
|
|
How to use NetscriptJS
|
|
----------------------
|
|
Working with NetscriptJS scripts is the same as Netscript 1.0 scripts. The only difference
|
|
is that NetscriptJS scripts use the ".ns" or ".js" extension rather than ".script". E.g.::
|
|
|
|
$ nano foo.ns
|
|
$ run foo.ns -t 100 arg1 arg2 arg3
|
|
exec("foo.ns", "purchasedServer1", "100", "randomArg");
|
|
|
|
The caveat when using NetscriptJS to write scripts is that your code must be
|
|
asynchronous. Furthermore, instead of using the global scope and executing your code
|
|
sequentially, NetscriptJS uses a :code:`main()` function as an entry point.
|
|
|
|
Furthermore, the "Netscript environment" must be passed into a NetscriptJS script through
|
|
the main function. This environment includes all of the pre-defined Netscript functions
|
|
(:code:`hack()`, :code:`exec`, etc.) as well as the arguments you pass to the script.
|
|
|
|
Therefore, the signature of the :code:`main()` function must be::
|
|
|
|
export async function main(ns) {
|
|
ns.print("Starting script here");
|
|
await ns.hack("foodnstuff"); //Use Netscript hack function
|
|
ns.print(ns.args); //The script arguments must be prefaced with ns as well
|
|
}
|
|
|
|
Here is a summary of all rules you need to follow when writing Netscript JS code:
|
|
|
|
* Write :code:`await` before any call to the following Netscript functions:
|
|
|
|
* hack
|
|
* grow
|
|
* weaken
|
|
* sleep
|
|
* prompt
|
|
* wget
|
|
|
|
* Any function that contains :code:`await` must be declared as :code:`async`
|
|
|
|
* Always :code:`await` any function that is marked as :code:`async`
|
|
|
|
* Any functions that you want to be visible from other scripts must be marked with :code:`export`.
|
|
|
|
* **Do not write any infinite loops without using a** :code:`sleep` **or one of the timed Netscript functions like** :code:`hack`. Doing so will crash your game.
|
|
|
|
* Any global variable declared in a NetscriptJS script is shared between all instances of that
|
|
script. For example, assume you write a script *foo.ns* and declared a global variable like so::
|
|
|
|
//foo.ns
|
|
let globalVariable;
|
|
|
|
export async function main(ns) {
|
|
globalVariable = ns.args.length;
|
|
while(true) {
|
|
ns.tprint(globalVariable);
|
|
await ns.sleep(3000);
|
|
}
|
|
}
|
|
|
|
Then, you ran multiple instances of *foo.ns*::
|
|
|
|
$ run foo.ns 1
|
|
$ run foo.ns 1 2 3
|
|
$ run foo.ns 1 2 3 4 5
|
|
|
|
Then all three instances of foo.ns will share the same instance of :code:`globalVariable`.
|
|
(In this example, the value of :code:`globalVariable` will be set to 5 because the
|
|
last instance of *foo.ns* to run has 5 arguments. This means that all three instances of
|
|
the script will repeatedly print the value 5).
|
|
|
|
These global variables can be thought of as `C++ static class members <https://www.tutorialspoint.com/cplusplus/cpp_static_members.htm>`_,
|
|
where a NetscriptJS script is a class and a global variable is a static member within that class.
|
|
|
|
Warnings
|
|
--------
|
|
The NetscriptJS evaluation engine works by converting your code into a blob URL and then
|
|
using a dynamic import to load your code as a module. Every unique NetscriptJS script
|
|
is loaded as its own module. This means that
|
|
making a small edit to a NetscriptJS script results in a new module being generated.
|
|
|
|
At this point, we have been unable to find a method for deleting modules from browsers so that
|
|
they get garbage collected.
|
|
|
|
The result is that these modules from NetscriptJS scripts accumulate in your browser,
|
|
using memory that never gets released. Over time, this results in a memory-leak type
|
|
situation that can slow down your computer.
|
|
|
|
Therefore, there are two recommendations for those who decide to use NetscriptJS:
|
|
|
|
1. Every now and then, close and re-open the game. This will clear all of the modules.
|
|
To be safe, I recommend **completely** closing the game's tab and then re-opening it.
|
|
Depending on your browser, a refresh or page reload does not always clear the modules.
|
|
|
|
2. Only use NetscriptJS scripts when needed. It is very unlikely that NetscriptJS
|
|
is needed for very simple scripts. By doing this, you will reduce the number of modules
|
|
that are loaded.
|
|
|
|
Examples
|
|
--------
|
|
|
|
**Script Scheduler (scriptScheduler.ns)**
|
|
|
|
This script shows some of the new functionality that is available in NetscriptJS,
|
|
including objects and object constructors, changing an object's prototype, and
|
|
importing other NetscriptJS scripts::
|
|
|
|
import {tprintColored} from "tprintColored.ns"; //Importing from other NetscriptJS scripts works!
|
|
|
|
function ScriptJob(params) {
|
|
if (params.fn == null) {
|
|
throw new Error("No Filename (fn) passed into ScriptJob ctor");
|
|
}
|
|
|
|
this.fn = params.fn;
|
|
this.threads = params.threads ? params.threads : 1;
|
|
this.args = params.args ? params.args : [];
|
|
}
|
|
|
|
ScriptJob.prototype.run = function(ns) {
|
|
let runArgs = [this.fn, this.threads].concat(this.args);
|
|
if (!ns.run.apply(this, runArgs)) {
|
|
throw new Error("Unable to run " + this.fn + " on " +ns.getHostname());
|
|
}
|
|
tprintColored("Running " + this.fn + " on " + ns.getHostname(), "blue");
|
|
}
|
|
|
|
ScriptJob.prototype.exec = function(ns, target) {
|
|
ns.scp(this.fn, target);
|
|
|
|
let execArgs = [this.fn, target, this.threads].concat(this.args);
|
|
if (!ns.exec.apply(this, execArgs)) {
|
|
throw new Error("Unable to execute " + this.fn + " on " + target);
|
|
}
|
|
tprintColored("Executing " + this.fn + " on " + target, "blue");
|
|
}
|
|
|
|
export async function main(ns) {
|
|
tprintColored("Starting scriptScheduler.ns", "red");
|
|
try {
|
|
let job = new ScriptJob({
|
|
fn: "test.js",
|
|
threads: 1,
|
|
args: ["foodnstuff"]
|
|
});
|
|
job.run(ns);
|
|
job.exec(ns, "foodnstuff");
|
|
} catch (e) {
|
|
ns.tprint("Exception thrown in scriptScheduler.ns: " + e);
|
|
}
|
|
}
|
|
|
|
Final Note
|
|
----------
|
|
NetscriptJS opens up a lot of possibilities when scripting. I look forward to seeing
|
|
the scripts that people come up with. Just remember that the power and capabilities of
|
|
NetscriptJS come with risks. Please backup your save if you're going to experiment with
|
|
NetscriptJS and report any serious exploits.
|
|
|
|
With great power comes great responsibility
|
|
|
|
Happy hacking
|