%clack

a nodejs library for sending IPC commands to an Urbit ship over Conn.c

Installation

To start using %clack in your node project install with npm:

npm install --save-dev @archetype-org/clack

Basic Usage

Basic usage has the following pattern.

import { Clack } from '@archetype-org/clack'

const clack = Clack({ ship: './path/to/your/zod' })
const noun = await clack.createDesk('%js-created')

In this example, the top level Clack object is imported from the package, and then initialized with the path to the ship you want to connect to through conn.c/kahn. Once it is setup, you can use the Clack object's methods, such as clack.createDesk() to script the behavior of your ship

Advanced Usage

If you know hoon, you can also directly send threads or any other %fyrd message to the ship using long form templatestrings for your hoon code. We expose the sendKahn() Function to allow this:

import { sendKahn, Thread, parseThreadResponse } from '@archetype-org/clack'

sendKahn({
	ship: './path/to/your/zod',
	hoon:  Thread(`
=/  m  (strand ,vase)
;<  ~  bind:m
~&  (add 40 2)
(poke [~zod %hood] %helm-hi !>(\'\'))
(pure:m !>([%res 'success']))
`),
	responseParser: parseThreadResponse,
})

Reference

Below You can find the full API reference for the methods and functions exported by the library. In addition to the top level clack object, we also expose some internal methods useful for advanced users sending custom messages through conn.c. These generally fall into two categories: encoding functions for doing bitwise operations to nouns an atoms (i.e. newt-encoding) and Khan specific types that provide more syntactic sugar for formatting nouns than using nockjs directly.

Clack Methods

Clack() Constructor

• Clack ( payload = { ship }) => clack: Clack

Takes a payload object that specifies a ship, and returns a Clack instance that controls that ship. Implemented as a closure, does not require the new keyword to create.

• payload.ship — string, path to the urbit pier you want to control
  • EX: './my-folder/zod'
• returns — Clack obj

clack.createDesk()

• clack.createDesk(deskName: string)

Takes a deskname and creates/mounts it in the controlled desk

• deskName — string, name of the desk you want to create. Must be a valid desk name (starts with % etc.)
• returns — Promise, a parsed thread response, whose tail is the noun returned by the thread

Reference — Encoding Functions

Encoding functions: converting between hoon Atoms and JS primitives, and newt encoding/decoding.

Dev Note: parts of these use python subprocesses to do byte manipulation because it is more strightforward than using Buffers for everything; there should be no system dependancies aside from a working python 2 or 3 installation

primitiveToAtom()

• primitiveToAtom(primitive: string) => atom: BigInt

Takes a string that casts to a JS primitive and transforms it into a nock atom; uses BigInt to represent the atom.

• primitive — string, must cast to a JS primitive or it will be interpreted as a string
  • EX: '420' => Number/@ud
  • EX: 'True' => Boolean/loobean
  • EX: 'foo' => String/cord
  • EX: 'foo' => %foo/@tas
• returns — atom, BigInt, the integer representing the nock atom

atomToPrimitive()

• atomToPrimitive(atom: Atom) => primitive: string

Takes a nockJS atom object and decodes the atom.number property to a string which can be parsed to a JS primitive

• atom — (atom : Atom), the nockjs Atom type
• returns — primitive, string, can be cast to a JS primitive
  • EX: '420' => Number/@ud
  • EX: 'True' => Boolean/loobean
  • EX: 'foo' => String
  • EX: 'foo' => %foo/@tas
    • Note: yes, this means that if you send %foo as part of the return atom, it will come over as 'foo' Not '%foo' on the JS side

newtDecode()

• newtDecode(buffer: Buffer) => atom: Atom

Takes a Buffer (received through Conn.c) and decodes it into a nockjs Atom object.

• buffer — buffer to decode
• returns — atom, a nockjs atom object, the atom.number property will still be a jammed noun, which will need to be cued for further decoding of it's children.

newtEncode()

• newtEncode(atom: Atom) => buffer: Buffer

Takes a nockjs Atom object (ideally a jammed noun) and encodes it with newt encoding for sending over the wire.

• atom — a nockjs atom, should be a jammed noun, if you want to send one atom, just jam it anyways
• returns — buffer, a buffer of a newt-encoded jammed noun, that can be sent to conn.c or %lick

Reference — Khan Functions

Fyrd()

• Fyrd(desk: string, thread: string, mark_out: string, mark_in: string, atom: string) => Fyrd

JS constructor for structuring a %fyrd in nockjs Cells.

• desk — name of the desk that contains the thread
• thread — thread to run (must be in desk)
  • EX: 'khan-eval' (NOT: '%khan-eval')
  • EX: 'work' (NOT: '%work' or -work)
• mark_out — string @tas determining the output type, must have a valid mark in the desk to run
  • EX: 'noun' (NOT: '%noun')
  • EX: 'text' (NOT: '%text')
• mark_in — string @tas determining the input type, must have a valid mark in the desk to run
  • EX: 'ted-eval' (NOT: '%ted-eval')
  • EX: 'noun' (NOT: '%noun')
• atom — the atom to send, can be a jammed noun or hoon code (as is the case with a custom thread)
• returns — fyrd,a Fyrd composed of Nockjs Cells

Thread()

• Thread(hoon: string) => Fyrd

JS constructor for structuring a %fyrd for running custom threads. wraps nockjs nouns.

• hoon — string, hoon code, a custom thread you want to run on the controlled ship
• returns — fyrd, a Fyrd composed of Nockjs Cells

parseThreadResponse()

• parseThreadResponse(data: Buffer) => noun: Cell

Decodes a buffer of data received from conn.c and parses the response. Assumes that the data is structured as the result of a %fyrd (e.g. begins with %avow and %noun). Returns null if it can't be parsed as a %fyrd response.

• data — Buffer, data to be decoded as a %fyrd response
• returns — noun, a nockjs Cell containing the return value of the thread with %avow and %noun stripped away from the head

sendKahn()

• sendKahn ({ ship, noun, responseParser }) => noun; Cell

Takes a payload with the ship to control, the noun to send, and the parser for getting the result, and then sends them to khan. Returns the parsed result.

• ship — string, path to the urbit pier you want to control
  • EX: './my-folder/zod'
• noun — nockjs noun to send to khan
  • can be Fyrd, Thread or something custom
• responseParser — Function, a response parser for parsing the expected return value of the noun you sent
  • EX: parseThreadResponse
• returns — noun, Cell, the nockjs Cell of the parsed return value from the message you sent to conn.c

Contributing & Tests

if you are developing or extending %clack you probably want to pull it from git instead of npm/yarn. It can be cloned from here:

git clone https://github.com/archetype-org/clack.git
cd ./clack

Once you are in the project, the tests can be run with:

npm test

clack uses jest, which will scan your project for files that fit the pattern \*.test.js and will run any test() functions defined in those files. You can add to the test suite in that file, or create additional ones as needed.

If you want to fix bugs or add features please submit a PR with the github issue, if it exists. included in the branch name.