shadowfacts.net/lib/activitypub/federate.ts

99 lines
2.8 KiB
TypeScript

import { promises as fs } from "fs";
import crypto from "crypto";
import uuidv4 from "uuid/v4";
import request from "request";
import { Database } from "sqlite3";
import { Activity, Article, Create, Actor, Follow, Accept } from "./activity";
import { URL } from "url";
const domain = process.env.DOMAIN;
function createActivity(article: Article): Create {
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": article.to,
"cc": article.cc,
"object": article
};
return createObject;
}
export async function fetchActor(url: string): Promise<Actor> {
return new Promise((resolve, reject) => {
request({
url,
headers: {
"Accept": "application/activity+json"
},
method: "GET",
json: true
}, (err, res) => {
if (err) reject(err);
else resolve(<Actor>res.body);
});
});
}
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: Create, db: Database) {
db.each("SELECT inbox FROM followers", (err, result) => {
if (err) {
console.log("Error getting followers: ", err);
return;
}
const inbox = "https://" + new URL(result.inbox).host + "/inbox";
console.log(`Federating ${activity.object.id} to ${inbox}`);
signAndSend(activity, inbox);
});
}
export default function federate(toFederate: [string, Article][], db: Database) {
for (const [id, article] of toFederate) {
sendToFollowers(createActivity(article), db);
db.run("UPDATE articles SET has_federated = 1 WHERE id = $id", {
$id: id
});
break;
}
}