shrub/pkg/npm/http-api/Urbit.ts
2021-04-22 07:17:39 -07:00

522 lines
15 KiB
TypeScript

import { isBrowser, isNode } from 'browser-or-node';
import { Action, Scry, Thread } from '@urbit/api';
import { fetchEventSource, EventSourceMessage, EventStreamContentType } from '@microsoft/fetch-event-source';
import { AuthenticationInterface, SubscriptionInterface, CustomEventHandler, PokeInterface, SubscriptionRequestInterface, headers, UrbitInterface, SSEOptions, PokeHandlers, Message } from './types';
import { uncamelize, hexString } from './utils';
/**
* A class for interacting with an urbit ship, given its URL and code
*/
export class Urbit implements UrbitInterface {
/**
* UID will be used for the channel: The current unix time plus a random hex string
*/
uid: string = `${Math.floor(Date.now() / 1000)}-${hexString(6)}`;
/**
* Last Event ID is an auto-updated index of which events have been sent over this channel
*/
lastEventId: number = 0;
lastAcknowledgedEventId: number = 0;
/**
* SSE Client is null for now; we don't want to start polling until it the channel exists
*/
sseClientInitialized: boolean = false;
/**
* Cookie gets set when we log in.
*/
cookie?: string | undefined;
/**
* A registry of requestId to successFunc/failureFunc
*
* These functions are registered during a +poke and are executed
* in the onServerEvent()/onServerError() callbacks. Only one of
* the functions will be called, and the outstanding poke will be
* removed after calling the success or failure function.
*/
outstandingPokes: Map<number, PokeHandlers> = new Map();
/**
* A registry of requestId to subscription functions.
*
* These functions are registered during a +subscribe and are
* executed in the onServerEvent()/onServerError() callbacks. The
* event function will be called whenever a new piece of data on this
* subscription is available, which may be 0, 1, or many times. The
* disconnect function may be called exactly once.
*/
outstandingSubscriptions: Map<number, SubscriptionRequestInterface> = new Map();
/**
* Ship can be set, in which case we can do some magic stuff like send chats
*/
ship?: string | null;
/**
* If verbose, logs output eagerly.
*/
verbose?: boolean;
onError?: (error: any) => void = null;
/** This is basic interpolation to get the channel URL of an instantiated Urbit connection. */
get channelUrl(): string {
return `${this.url}/~/channel/${this.uid}`;
}
get fetchOptions(): any {
const headers: headers = {
'Content-Type': 'application/json',
};
if (!isBrowser) {
headers.Cookie = this.cookie;
}
return {
credentials: 'include',
accept: '*',
headers
};
}
/**
* Constructs a new Urbit connection.
*
* @param url The URL (with protocol and port) of the ship to be accessed
* @param code The access code for the ship at that address
*/
constructor(
public url: string,
public code: string
) {
if (isBrowser) {
window.addEventListener('beforeunload', this.delete);
}
return this;
}
/**
* All-in-one hook-me-up.
*
* Given a ship, url, and code, this returns an airlock connection
* that is ready to go. It `|hi`s itself to create the channel,
* then opens the channel via EventSource.
*
* @param AuthenticationInterface
*/
static async authenticate({ ship, url, code, verbose = false }: AuthenticationInterface) {
const airlock = new Urbit(`http://${url}`, code);
airlock.verbose = verbose;
airlock.ship = ship;
await airlock.connect();
await airlock.poke({ app: 'hood', mark: 'helm-hi', json: 'opening airlock' });
await airlock.eventSource();
return airlock;
}
/**
* Connects to the Urbit ship. Nothing can be done until this is called.
* That's why we roll it into this.authenticate
*/
async connect(): Promise<void> {
if (this.verbose) {
console.log(`password=${this.code} `, isBrowser ? "Connecting in browser context at " + `${this.url}/~/login` : "Connecting from node context");
}
return fetch(`${this.url}/~/login`, {
method: 'post',
body: `password=${this.code}`,
credentials: 'include',
}).then(response => {
if (this.verbose) {
console.log('Received authentication response', response);
}
const cookie = response.headers.get('set-cookie');
if (!this.ship) {
this.ship = new RegExp(/urbauth-~([\w-]+)/).exec(cookie)[1];
}
if (!isBrowser) {
this.cookie = cookie;
}
});
}
/**
* Initializes the SSE pipe for the appropriate channel.
*/
eventSource(): void {
if (!this.sseClientInitialized) {
const sseOptions: SSEOptions = {
headers: {}
};
if (isBrowser) {
sseOptions.withCredentials = true;
} else if (isNode) {
sseOptions.headers.Cookie = this.cookie;
}
if (this.lastEventId === 0) {
// Can't receive events until the channel is open
this.poke({ app: 'hood', mark: 'helm-hi', json: 'Opening API channel' });
}
fetchEventSource(this.channelUrl, {
...this.fetchOptions,
openWhenHidden: true,
onopen: async (response) => {
if (this.verbose) {
console.log('Opened eventsource', response);
}
if (response.ok && response.headers.get('content-type') === EventStreamContentType) {
return; // everything's good
} else if (response.status >= 400 && response.status < 500 && response.status !== 429) {
if (this.onError) {
this.onError(response.statusText);
} else {
throw new Error();
}
} else {
if (this.onError) {
this.onError(response.statusText);
} else {
throw new Error();
}
}
},
onmessage: (event: EventSourceMessage) => {
if (this.verbose) {
console.log('Received SSE: ', event);
}
if (!event.id) return;
this.ack(Number(event.id));
if (event.data && JSON.parse(event.data)) {
const data: any = JSON.parse(event.data);
if (data.response === 'diff') {
this.clearQueue();
}
if (data.response === 'poke' && this.outstandingPokes.has(data.id)) {
const funcs = this.outstandingPokes.get(data.id);
if (data.hasOwnProperty('ok')) {
funcs.onSuccess();
} else if (data.hasOwnProperty('err')) {
funcs.onError(data.err);
} else {
console.error('Invalid poke response', data);
}
this.outstandingPokes.delete(data.id);
} else if (data.response === 'subscribe' ||
(data.response === 'poke' && this.outstandingSubscriptions.has(data.id))) {
const funcs = this.outstandingSubscriptions.get(data.id);
if (data.hasOwnProperty('err')) {
funcs.err(data.err);
this.outstandingSubscriptions.delete(data.id);
}
} else if (data.response === 'diff' && this.outstandingSubscriptions.has(data.id)) {
const funcs = this.outstandingSubscriptions.get(data.id);
funcs.event(data.json);
} else if (data.response === 'quit' && this.outstandingSubscriptions.has(data.id)) {
const funcs = this.outstandingSubscriptions.get(data.id);
funcs.quit(data);
this.outstandingSubscriptions.delete(data.id);
} else {
console.log('Unrecognized response', data);
}
}
},
onerror: (error) => {
if (this.onError) {
this.onError(error);
} else {
throw error;
}
}
});
this.sseClientInitialized = true;
}
return;
}
/**
* Autoincrements the next event ID for the appropriate channel.
*/
getEventId(): number {
this.lastEventId = Number(this.lastEventId) + 1;
return this.lastEventId;
}
/**
* Acknowledges an event.
*
* @param eventId The event to acknowledge.
*/
async ack(eventId: number): Promise<number | void> {
const message: Message = {
action: 'ack',
'event-id': eventId
};
await this.sendJSONtoChannel(message);
return eventId;
}
/**
* This is a wrapper method that can be used to send any action with data.
*
* Every message sent has some common parameters, like method, headers, and data
* structure, so this method exists to prevent duplication.
*
* @param action The action to send
* @param data The data to send with the action
*
* @returns void | number If successful, returns the number of the message that was sent
*/
// async sendMessage(action: Action, data?: object): Promise<number | void> {
// const id = this.getEventId();
// if (this.verbose) {
// console.log(`Sending message ${id}:`, action, data,);
// }
// const message: Message = { id, action, ...data };
// await this.sendJSONtoChannel(message);
// return id;
// }
outstandingJSON: Message[] = [];
debounceTimer: any = null;
debounceInterval = 500;
calm = true;
sendJSONtoChannel(json: Message): Promise<boolean | void> {
this.outstandingJSON.push(json);
return this.processQueue();
}
processQueue(): Promise<boolean | void> {
return new Promise(async (resolve, reject) => {
const process = async () => {
if (this.calm) {
if (this.outstandingJSON.length === 0) resolve(true);
this.calm = false; // We are now occupied
const json = this.outstandingJSON;
const body = JSON.stringify(json);
this.outstandingJSON = [];
if (body === '[]') {
this.calm = true;
return resolve(false);
}
try {
await fetch(this.channelUrl, {
...this.fetchOptions,
method: 'PUT',
body
});
} catch (error) {
json.forEach(failed => this.outstandingJSON.push(failed));
if (this.onError) {
this.onError(error);
} else {
throw error;
}
}
this.calm = true;
if (!this.sseClientInitialized) {
this.eventSource(); // We can open the channel for subscriptions once we've sent data over it
}
resolve(true);
} else {
clearTimeout(this.debounceTimer);
this.debounceTimer = setTimeout(process, this.debounceInterval);
resolve(false);
}
}
this.debounceTimer = setTimeout(process, this.debounceInterval);
});
}
// resetDebounceTimer() {
// if (this.debounceTimer) {
// clearTimeout(this.debounceTimer);
// this.debounceTimer = null;
// }
// this.calm = false;
// this.debounceTimer = setTimeout(() => {
// this.calm = true;
// }, this.debounceInterval);
// }
clearQueue() {
clearTimeout(this.debounceTimer);
this.debounceTimer = null;
}
/**
* Pokes a ship with data.
*
* @param app The app to poke
* @param mark The mark of the data being sent
* @param json The data to send
*/
poke<T>(params: PokeInterface<T>): Promise<number> {
const {
app,
mark,
json,
ship,
onSuccess,
onError
} = {
onSuccess: () => { },
onError: () => { },
ship: this.ship,
...params
};
return new Promise((resolve, reject) => {
const message: Message = {
id: this.getEventId(),
action: 'poke',
ship,
app,
mark,
json
};
this.outstandingPokes.set(message.id, {
onSuccess: () => {
onSuccess();
resolve(message.id);
},
onError: (event) => {
onError(event);
reject(event.err);
}
});
this.sendJSONtoChannel(message).then(() => {
resolve(message.id);
});
});
}
/**
* Subscribes to a path on an app on a ship.
*
* @param app The app to subsribe to
* @param path The path to which to subscribe
* @param handlers Handlers to deal with various events of the subscription
*/
async subscribe(params: SubscriptionRequestInterface): Promise<number> {
const {
app,
path,
ship,
err,
event,
quit
} = {
err: () => { },
event: () => { },
quit: () => { },
ship: this.ship,
...params
};
const message: Message = {
id: this.getEventId(),
action: 'subscribe',
ship,
app,
path
};
this.outstandingSubscriptions.set(message.id, {
app, path, err, event, quit
});
await this.sendJSONtoChannel(message);
return message.id;
}
/**
* Unsubscribes to a given subscription.
*
* @param subscription
*/
async unsubscribe(subscription: number) {
return this.sendJSONtoChannel({
id: this.getEventId(),
action: 'unsubscribe',
subscription
}).then(() => {
this.outstandingSubscriptions.delete(subscription);
});
}
/**
* Deletes the connection to a channel.
*/
delete() {
if (isBrowser) {
navigator.sendBeacon(this.channelUrl, JSON.stringify([{
action: 'delete'
}]));
} else {
// TODO
// this.sendMessage('delete');
}
}
/**
*
* @param app The app into which to scry
* @param path The path at which to scry
*/
async scry(params: Scry): Promise<void | any> {
const { app, path } = params;
const response = await fetch(`${this.url}/~/scry/${app}${path}.json`, this.fetchOptions);
return await response.json();
}
/**
*
* @param inputMark The mark of the data being sent
* @param outputMark The mark of the data being returned
* @param threadName The thread to run
* @param body The data to send to the thread
*/
async thread<T>(params: Thread<T>): Promise<T> {
const { inputMark, outputMark, threadName, body } = params;
const res = await fetch(`${this.url}/spider/${inputMark}/${threadName}/${outputMark}.json`, {
...this.fetchOptions,
method: 'POST',
body: JSON.stringify(body)
});
return res.json();
}
/**
* Utility function to connect to a ship that has its *.arvo.network domain configured.
*
* @param name Name of the ship e.g. zod
* @param code Code to log in
*/
static async onArvoNetwork(ship: string, code: string): Promise<Urbit> {
const url = `https://${ship}.arvo.network`;
return await Urbit.authenticate({ ship, url, code });
}
}
export default Urbit;