joerglohrerde/publish/src/core/blossom.ts

89 lines
2.5 KiB
TypeScript

import { encodeBase64 } from '@std/encoding/base64'
import type { Signer } from './signer.ts'
import type { UnsignedEvent } from './event.ts'
export interface BlossomClient {
fetch(url: string, init: RequestInit): Promise<Response>
}
export interface UploadArgs {
data: Uint8Array
fileName: string
mimeType: string
servers: string[]
signer: Signer
client?: BlossomClient
}
export interface UploadReport {
ok: string[]
failed: string[]
primaryUrl: string
sha256: string
}
async function sha256Hex(data: Uint8Array): Promise<string> {
const hash = await crypto.subtle.digest('SHA-256', data as BufferSource)
return Array.from(new Uint8Array(hash))
.map((b) => b.toString(16).padStart(2, '0'))
.join('')
}
async function buildAuth(signer: Signer, hash: string): Promise<string> {
const pubkey = await signer.getPublicKey()
const auth: UnsignedEvent = {
kind: 24242,
pubkey,
created_at: Math.floor(Date.now() / 1000),
tags: [
['t', 'upload'],
['x', hash],
['expiration', String(Math.floor(Date.now() / 1000) + 300)],
],
content: '',
}
const signed = await signer.signEvent(auth)
return 'Nostr ' + encodeBase64(new TextEncoder().encode(JSON.stringify(signed)))
}
async function uploadOne(
server: string,
data: Uint8Array,
mimeType: string,
auth: string,
client: BlossomClient,
): Promise<{ ok: boolean; url?: string }> {
try {
const resp = await client.fetch(server + '/upload', {
method: 'PUT',
headers: { authorization: auth, 'content-type': mimeType },
body: data as BodyInit,
})
if (!resp.ok) return { ok: false }
const json = await resp.json()
return { ok: true, url: json.url }
} catch {
return { ok: false }
}
}
const defaultClient: BlossomClient = { fetch: (u, i) => fetch(u, i) }
export async function uploadBlob(args: UploadArgs): Promise<UploadReport> {
const client = args.client ?? defaultClient
const hash = await sha256Hex(args.data)
const auth = await buildAuth(args.signer, hash)
const results = await Promise.all(
args.servers.map((s) =>
uploadOne(s, args.data, args.mimeType, auth, client).then((r) => ({ server: s, ...r }))
),
)
const ok = results.filter((r) => r.ok).map((r) => r.server)
const failed = results.filter((r) => !r.ok).map((r) => r.server)
if (ok.length === 0) {
throw new Error(`all blossom servers failed for ${args.fileName}`)
}
const first = results.find((r) => r.ok && r.url)!
return { ok, failed, primaryUrl: first.url!, sha256: hash }
}