shadowfacts.net/lib/activitypub/federate.ts

145 lines
4.4 KiB
TypeScript

import { promises as fs } from "fs";
import crypto from "crypto";
import uuidv4 from "uuid/v4";
import request from "request";
import {
Activity,
ArticleObject,
ActorObject,
CreateActivity,
NoteObject
} from "./activity";
import { URL } from "url";
import { getConnection } from "typeorm";
import Actor from "../entity/Actor";
import Article from "../entity/Article";
const domain = process.env.DOMAIN;
export function createActivity(object: ArticleObject | NoteObject): CreateActivity {
const uuid = uuidv4();
const createObject = {
"@context": [
"https://www.w3.org/ns/activitystreams"
],
"type": "Create",
"id": `https://${domain}/ap/${uuid}`,
"actor": `https://${domain}/ap/actor`,
"to": object.to,
"cc": object.cc,
"object": object
};
return createObject;
}
export async function getActor(url: string, forceUpdate: boolean = false): Promise<ActorObject | null> {
if (!forceUpdate) {
try {
const cached = await getCachedActor(url);
if (cached) return cached;
} catch (err) {
console.error(`Encountered error getting cached actor ${url}`, err);
}
}
const remote = await fetchActor(url);
if (remote) cacheActor(remote);
return remote;
}
export async function getCachedActor(url: string): Promise<ActorObject | null> {
const result = await getConnection().manager.findByIds(Actor, [url]);
if (result.length > 0) {
const actor = result[0];
return actor.actorObject;
} else {
return null;
}
}
async function cacheActor(actorObject: ActorObject) {
function getIconUrl(icon: string | object): string {
return icon instanceof String ? icon : (icon as any).url;
}
const iconURL = !actorObject.icon ? null : actorObject.icon instanceof Array ? getIconUrl(actorObject.icon[0]) : getIconUrl(actorObject.icon);
const actor = new Actor();
actor.id = actorObject.id;
actor.actorObject = actorObject;
actor.displayName = actorObject.name;
actor.inbox = actorObject.inbox;
actor.iconURL = iconURL;
actor.publicKeyPem = actorObject.publicKey.publicKeyPem;
actor.isFollower = false;
await getConnection().manager.save(actor);
}
async function fetchActor(url?: string): Promise<ActorObject | null> {
if (!url) {
return Promise.resolve(null);
}
return new Promise((resolve, reject) => {
request({
url,
headers: {
"Accept": "application/activity+json"
},
method: "GET",
json: true
}, (err, res) => {
if (err) reject(err);
else resolve(res.body ? res.body as ActorObject : null);
});
});
}
export async function signAndSend(activity: Activity, inbox: string) {
const targetDomain = new URL(inbox).hostname;
const inboxFragment = inbox.replace("https://" + targetDomain, "");
const date = new Date();
const privKey = (await fs.readFile(process.env.PRIV_KEY_PEM!)).toString();
const signer = crypto.createSign("sha256");
const stringToSign = `(request-target): post ${inboxFragment}\nhost: ${targetDomain}\ndate: ${date.toUTCString()}`;
signer.update(stringToSign);
signer.end();
const signature = signer.sign(privKey, "base64");
const header = `keyId="https://${domain}/ap/actor#main-key",headers="(request-target) host date",signature="${signature}"`;
console.log("Sending:", activity);
console.log("stringToSign:", stringToSign);
console.log("Signature: " + header);
request({
url: inbox,
headers: {
"Host": targetDomain,
"Date": date.toUTCString(),
"Signature": header,
"Accept": "application/activity+json, application/json"
},
method: "POST",
json: true,
body: activity
}, (err, res) => {
console.log("Sent message to inbox at", targetDomain);
console.log("Response status code", res.statusCode);
console.log(res.body);
if (err) console.log("Error:", err, res);
});
}
async function sendToFollowers(activity: CreateActivity) {
const followers = await getConnection().createQueryBuilder().select().from(Actor, "actor").where("actor.isFollower = :isFollower", { isFollower: true }).getMany();
const inboxes = followers.map(it => "https://" + new URL(it.inbox).host + "/inbox");
// convert to a Set to deduplicate inboxes
(new Set(inboxes)).forEach(inbox => {
console.log(`Federating ${activity.object.id} to ${inbox}`);
signAndSend(activity, inbox);
});
}
export default async function federate(toFederate: [string, ArticleObject][]) {
for (const [id, article] of toFederate) {
sendToFollowers(createActivity(article));
await getConnection().manager.update(Article, id, { hasFederated: true });
}
}