misskey/src/remote/activitypub/resolver.ts
2018-04-04 23:12:35 +09:00

63 lines
1.3 KiB
TypeScript

import { IObject } from "./type";
const request = require('request-promise-native');
export default class Resolver {
private history: Set<string>;
constructor() {
this.history = new Set();
}
public async resolveCollection(value) {
const collection = typeof value === 'string'
? await this.resolve(value)
: value;
switch (collection.type) {
case 'Collection':
collection.objects = collection.object.items;
break;
case 'OrderedCollection':
collection.objects = collection.object.orderedItems;
break;
default:
throw new Error(`unknown collection type: ${collection.type}`);
}
return collection;
}
public async resolve(value): Promise<IObject> {
if (typeof value !== 'string') {
return value;
}
if (this.history.has(value)) {
throw new Error('cannot resolve already resolved one');
}
this.history.add(value);
const object = await request({
url: value,
headers: {
Accept: 'application/activity+json, application/ld+json'
},
json: true
});
if (object === null || (
Array.isArray(object['@context']) ?
!object['@context'].includes('https://www.w3.org/ns/activitystreams') :
object['@context'] !== 'https://www.w3.org/ns/activitystreams'
)) {
throw new Error('invalid response');
}
return object;
}
}