bsky-app/src/lib/api/feed/custom.ts

142 lines
3.6 KiB
TypeScript

import {
AppBskyFeedDefs,
AppBskyFeedGetFeed as GetCustomFeed,
BskyAgent,
jsonStringToLex,
} from '@atproto/api'
import {getContentLanguages} from '#/state/preferences/languages'
import {FeedAPI, FeedAPIResponse} from './types'
import {createBskyTopicsHeader, isBlueskyOwnedFeed} from './utils'
export class CustomFeedAPI implements FeedAPI {
agent: BskyAgent
params: GetCustomFeed.QueryParams
userInterests?: string
constructor({
agent,
feedParams,
userInterests,
}: {
agent: BskyAgent
feedParams: GetCustomFeed.QueryParams
userInterests?: string
}) {
this.agent = agent
this.params = feedParams
this.userInterests = userInterests
}
async peekLatest(): Promise<AppBskyFeedDefs.FeedViewPost> {
const contentLangs = getContentLanguages().join(',')
const res = await this.agent.app.bsky.feed.getFeed(
{
...this.params,
limit: 1,
},
{headers: {'Accept-Language': contentLangs}},
)
return res.data.feed[0]
}
async fetch({
cursor,
limit,
}: {
cursor: string | undefined
limit: number
}): Promise<FeedAPIResponse> {
const contentLangs = getContentLanguages().join(',')
const agent = this.agent
const isBlueskyOwned = isBlueskyOwnedFeed(this.params.feed)
const res = agent.did
? await this.agent.app.bsky.feed.getFeed(
{
...this.params,
cursor,
limit,
},
{
headers: {
...(isBlueskyOwned
? createBskyTopicsHeader(this.userInterests)
: {}),
'Accept-Language': contentLangs,
},
},
)
: await loggedOutFetch({...this.params, cursor, limit})
if (res.success) {
// NOTE
// some custom feeds fail to enforce the pagination limit
// so we manually truncate here
// -prf
if (res.data.feed.length > limit) {
res.data.feed = res.data.feed.slice(0, limit)
}
return {
cursor: res.data.feed.length ? res.data.cursor : undefined,
feed: res.data.feed,
}
}
return {
feed: [],
}
}
}
// HACK
// we want feeds to give language-specific results immediately when a
// logged-out user changes their language. this comes with two problems:
// 1. not all languages have content, and
// 2. our public caching layer isnt correctly busting against the accept-language header
// for now we handle both of these with a manual workaround
// -prf
async function loggedOutFetch({
feed,
limit,
cursor,
}: {
feed: string
limit: number
cursor?: string
}) {
let contentLangs = getContentLanguages().join(',')
// manually construct fetch call so we can add the `lang` cache-busting param
let res = await fetch(
`https://api.bsky.app/xrpc/app.bsky.feed.getFeed?feed=${feed}${
cursor ? `&cursor=${cursor}` : ''
}&limit=${limit}&lang=${contentLangs}`,
{method: 'GET', headers: {'Accept-Language': contentLangs}},
)
let data = res.ok ? jsonStringToLex(await res.text()) : null
if (data?.feed?.length) {
return {
success: true,
data,
}
}
// no data, try again with language headers removed
res = await fetch(
`https://api.bsky.app/xrpc/app.bsky.feed.getFeed?feed=${feed}${
cursor ? `&cursor=${cursor}` : ''
}&limit=${limit}`,
{method: 'GET', headers: {'Accept-Language': ''}},
)
data = res.ok ? jsonStringToLex(await res.text()) : null
if (data?.feed?.length) {
return {
success: true,
data,
}
}
return {
success: false,
data: {feed: []},
}
}