migrate the custom, merge and home feed apis to the appview client

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/lib/api/feed/custom.ts

@@ -1,46 +1,46 @@
-import {
-  type AppBskyFeedDefs,
-  type AppBskyFeedGetFeed as GetCustomFeed,
-  AtpAgent,
-  jsonStringToLex,
-} from '@atproto/api'
+import {type AppBskyFeedDefs, AtpAgent, jsonStringToLex} from '@atproto/api'
+import {type Client, type XrpcRequestParams} from '@atproto/lex'
 
 import {
   getAppLanguageAsContentLanguage,
   getContentLanguages,
 } from '#/state/preferences/languages'
+import {app} from '#/lexicons'
 import {type FeedAPI, type FeedAPIResponse} from './types'
 import {createBskyTopicsHeader, isBlueskyOwnedFeed} from './utils'
 
+type GetCustomFeedParams = XrpcRequestParams<typeof app.bsky.feed.getFeed.main>
+
 export class CustomFeedAPI implements FeedAPI {
-  agent: AtpAgent
-  params: GetCustomFeed.QueryParams
+  client: Client
+  params: GetCustomFeedParams
   userInterests?: string
 
   constructor({
-    agent,
+    client,
     feedParams,
     userInterests,
   }: {
-    agent: AtpAgent
-    feedParams: GetCustomFeed.QueryParams
+    client: Client
+    feedParams: GetCustomFeedParams
     userInterests?: string
   }) {
-    this.agent = agent
+    this.client = client
     this.params = feedParams
     this.userInterests = userInterests
   }
 
   async peekLatest(): Promise<AppBskyFeedDefs.FeedViewPost> {
     const contentLangs = getContentLanguages().join(',')
-    const res = await this.agent.app.bsky.feed.getFeed(
+    const data = await this.client.call(
+      app.bsky.feed.getFeed,
       {
         ...this.params,
         limit: 1,
       },
       {headers: {'Accept-Language': contentLangs}},
     )
-    return res.data.feed[0]
+    return data.feed[0]
   }
 
   async fetch({
@@ -51,11 +51,17 @@ export class CustomFeedAPI implements FeedAPI {
     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(
+    /*
+     * The authed branch rejects on failure, so the error propagates to the
+     * query and drives the feed error UI (feedgen offline, misconfigured, rate
+     * limited). Only the logged-out branch can resolve without data, and it
+     * signals that with a null body.
+     */
+    const data = this.client.did
+      ? await this.client.call(
+          app.bsky.feed.getFeed,
           {
             ...this.params,
             cursor,
@@ -71,21 +77,22 @@ export class CustomFeedAPI implements FeedAPI {
           },
         )
       : 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)
-      }
+
+    if (!data) {
       return {
-        cursor: res.data.feed.length ? res.data.cursor : undefined,
-        feed: res.data.feed,
+        feed: [],
       }
     }
+
+    // NOTE
+    // some custom feeds fail to enforce the pagination limit
+    // so we manually truncate here
+    // -prf
+    const feed =
+      data.feed.length > limit ? data.feed.slice(0, limit) : data.feed
     return {
-      feed: [],
+      cursor: feed.length ? data.cursor : undefined,
+      feed,
     }
   }
 }
@@ -105,7 +112,7 @@ async function loggedOutFetch({
   feed: string
   limit: number
   cursor?: string
-}) {
+}): Promise<app.bsky.feed.getFeed.$OutputBody | null> {
   let contentLangs = getAppLanguageAsContentLanguage()
 
   /**
@@ -128,14 +135,15 @@ async function loggedOutFetch({
       headers: {'Accept-Language': contentLangs, ...labelersHeader},
     },
   )
+  /*
+   * The response is hand-decoded rather than validated, so the lex output shape
+   * is asserted here just as the old-world one was.
+   */
   let data = res.ok
-    ? (jsonStringToLex(await res.text()) as GetCustomFeed.OutputSchema)
+    ? (jsonStringToLex(await res.text()) as app.bsky.feed.getFeed.$OutputBody)
     : null
   if (data?.feed?.length) {
-    return {
-      success: true,
-      data,
-    }
+    return data
   }
 
   // no data, try again with language headers removed
@@ -146,17 +154,11 @@ async function loggedOutFetch({
     {method: 'GET', headers: {'Accept-Language': '', ...labelersHeader}},
   )
   data = res.ok
-    ? (jsonStringToLex(await res.text()) as GetCustomFeed.OutputSchema)
+    ? (jsonStringToLex(await res.text()) as app.bsky.feed.getFeed.$OutputBody)
     : null
   if (data?.feed?.length) {
-    return {
-      success: true,
-      data,
-    }
+    return data
   }
 
-  return {
-    success: false,
-    data: {feed: []},
-  }
+  return null
 }

src/lib/api/feed/home.ts

@@ -1,4 +1,6 @@
-import {type AppBskyFeedDefs, type AtpAgent} from '@atproto/api'
+import {type AppBskyFeedDefs} from '@atproto/api'
+import {type Client} from '@atproto/lex'
+import {type AtUriString} from '@atproto/syntax'
 
 import {PROD_DEFAULT_FEED} from '#/lib/constants'
 import {CustomFeedAPI} from './custom'
@@ -27,7 +29,7 @@ export const FALLBACK_MARKER_POST: AppBskyFeedDefs.FeedViewPost = {
 }
 
 export class HomeFeedAPI implements FeedAPI {
-  agent: AtpAgent
+  client: Client
   following: FollowingFeedAPI
   discover: CustomFeedAPI
   usingDiscover = false
@@ -36,25 +38,25 @@ export class HomeFeedAPI implements FeedAPI {
 
   constructor({
     userInterests,
-    agent,
+    client,
   }: {
     userInterests?: string
-    agent: AtpAgent
+    client: Client
   }) {
-    this.agent = agent
-    this.following = new FollowingFeedAPI({agent})
+    this.client = client
+    this.following = new FollowingFeedAPI({client})
     this.discover = new CustomFeedAPI({
-      agent,
-      feedParams: {feed: PROD_DEFAULT_FEED('whats-hot')},
+      client,
+      feedParams: {feed: PROD_DEFAULT_FEED('whats-hot') as AtUriString},
     })
     this.userInterests = userInterests
   }
 
   reset() {
-    this.following = new FollowingFeedAPI({agent: this.agent})
+    this.following = new FollowingFeedAPI({client: this.client})
     this.discover = new CustomFeedAPI({
-      agent: this.agent,
-      feedParams: {feed: PROD_DEFAULT_FEED('whats-hot')},
+      client: this.client,
+      feedParams: {feed: PROD_DEFAULT_FEED('whats-hot') as AtUriString},
       userInterests: this.userInterests,
     })
     this.usingDiscover = false

src/lib/api/feed/merge.ts

@@ -1,8 +1,6 @@
-import {
-  type AppBskyFeedDefs,
-  type AppBskyFeedGetTimeline,
-  type AtpAgent,
-} from '@atproto/api'
+import {type AppBskyFeedDefs} from '@atproto/api'
+import {type Client} from '@atproto/lex'
+import {type AtUriString} from '@atproto/syntax'
 import shuffle from 'lodash.shuffle'
 
 import {bundleAsync} from '#/lib/async/bundle'
@@ -10,6 +8,7 @@ import {timeout} from '#/lib/async/timeout'
 import {feedUriToHref} from '#/lib/strings/url-helpers'
 import {getContentLanguages} from '#/state/preferences/languages'
 import {type FeedParams} from '#/state/queries/post-feed'
+import {app} from '#/lexicons'
 import {FeedTuner} from '../feed-manip'
 import {type FeedTunerFn} from '../feed-manip'
 import {
@@ -22,9 +21,19 @@ import {createBskyTopicsHeader, isBlueskyOwnedFeed} from './utils'
 const REQUEST_WAIT_MS = 500 // 500ms
 const POST_AGE_CUTOFF = 60e3 * 60 * 24 // 24hours
 
+/**
+ * A page of feed items, or `null` when the source could not produce one. Only
+ * sources that deliberately swallow their own errors return `null`; the rest
+ * reject so the error reaches the caller.
+ */
+type MergeFeedPage = {
+  cursor?: string
+  feed: AppBskyFeedDefs.FeedViewPost[]
+} | null
+
 export class MergeFeedAPI implements FeedAPI {
   userInterests?: string
-  agent: AtpAgent
+  client: Client
   params: FeedParams
   feedTuners: FeedTunerFn[]
   following: MergeFeedSource_Following
@@ -34,29 +43,29 @@ export class MergeFeedAPI implements FeedAPI {
   sampleCursor = 0
 
   constructor({
-    agent,
+    client,
     feedParams,
     feedTuners,
     userInterests,
   }: {
-    agent: AtpAgent
+    client: Client
     feedParams: FeedParams
     feedTuners: FeedTunerFn[]
     userInterests?: string
   }) {
-    this.agent = agent
+    this.client = client
     this.params = feedParams
     this.feedTuners = feedTuners
     this.userInterests = userInterests
     this.following = new MergeFeedSource_Following({
-      agent: this.agent,
+      client: this.client,
       feedTuners: this.feedTuners,
     })
   }
 
   reset() {
     this.following = new MergeFeedSource_Following({
-      agent: this.agent,
+      client: this.client,
       feedTuners: this.feedTuners,
     })
     this.customFeeds = []
@@ -68,7 +77,7 @@ export class MergeFeedAPI implements FeedAPI {
         this.params.mergeFeedSources.map(
           feedUri =>
             new MergeFeedSource_Custom({
-              agent: this.agent,
+              client: this.client,
               feedUri,
               feedTuners: this.feedTuners,
               userInterests: this.userInterests,
@@ -81,10 +90,10 @@ export class MergeFeedAPI implements FeedAPI {
   }
 
   async peekLatest(): Promise<AppBskyFeedDefs.FeedViewPost> {
-    const res = await this.agent.getTimeline({
+    const data = await this.client.call(app.bsky.feed.getTimeline, {
       limit: 1,
     })
-    return res.data.feed[0]
+    return data.feed[0]
   }
 
   async fetch({
@@ -175,7 +184,7 @@ export class MergeFeedAPI implements FeedAPI {
 }
 
 class MergeFeedSource {
-  agent: AtpAgent
+  client: Client
   feedTuners: FeedTunerFn[]
   sourceInfo: ReasonFeedSource | undefined
   cursor: string | undefined = undefined
@@ -183,13 +192,13 @@ class MergeFeedSource {
   hasMore = true
 
   constructor({
-    agent,
+    client,
     feedTuners,
   }: {
-    agent: AtpAgent
+    client: Client
     feedTuners: FeedTunerFn[]
   }) {
-    this.agent = agent
+    this.client = client
     this.feedTuners = feedTuners
   }
 
@@ -210,11 +219,11 @@ class MergeFeedSource {
   }
 
   _fetchNextInner = bundleAsync(async (n: number) => {
-    const res = await this._getFeed(this.cursor, n)
-    if (res.success) {
-      this.cursor = res.data.cursor
-      if (res.data.feed.length) {
-        this.queue = this.queue.concat(res.data.feed)
+    const page = await this._getFeed(this.cursor, n)
+    if (page) {
+      this.cursor = page.cursor
+      if (page.feed.length) {
+        this.queue = this.queue.concat(page.feed)
       } else {
         this.hasMore = false
       }
@@ -226,7 +235,7 @@ class MergeFeedSource {
   protected _getFeed(
     _cursor: string | undefined,
     _limit: number,
-  ): Promise<AppBskyFeedGetTimeline.Response> {
+  ): Promise<MergeFeedPage> {
     throw new Error('Must be overridden')
   }
 }
@@ -238,42 +247,49 @@ class MergeFeedSource_Following extends MergeFeedSource {
     return this._fetchNextInner(n)
   }
 
+  /*
+   * No error handling: a failed timeline read rejects, which is what the agent
+   * did too, so the error still reaches `MergeFeedAPI.fetch` and the query.
+   */
   protected async _getFeed(
     cursor: string | undefined,
     limit: number,
-  ): Promise<AppBskyFeedGetTimeline.Response> {
-    const res = await this.agent.getTimeline({cursor, limit})
+  ): Promise<MergeFeedPage> {
+    const data = await this.client.call(app.bsky.feed.getTimeline, {
+      cursor,
+      limit,
+    })
     // run the tuner pre-emptively to ensure better mixing
-    const slices = this.tuner.tune(res.data.feed, {
+    const slices = this.tuner.tune(data.feed, {
       dryRun: false,
     })
-    res.data.feed = slices.map(slice => slice._feedPost)
-    return res
+    return {
+      cursor: data.cursor,
+      feed: slices.map(slice => slice._feedPost),
+    }
   }
 }
 
 class MergeFeedSource_Custom extends MergeFeedSource {
-  agent: AtpAgent
   minDate: Date
   feedUri: string
   userInterests?: string
 
   constructor({
-    agent,
+    client,
     feedUri,
     feedTuners,
     userInterests,
   }: {
-    agent: AtpAgent
+    client: Client
     feedUri: string
     feedTuners: FeedTunerFn[]
     userInterests?: string
   }) {
     super({
-      agent,
+      client,
       feedTuners,
     })
-    this.agent = agent
     this.feedUri = feedUri
     this.userInterests = userInterests
     this.sourceInfo = {
@@ -287,15 +303,16 @@ class MergeFeedSource_Custom extends MergeFeedSource {
   protected async _getFeed(
     cursor: string | undefined,
     limit: number,
-  ): Promise<AppBskyFeedGetTimeline.Response> {
+  ): Promise<MergeFeedPage> {
     try {
       const contentLangs = getContentLanguages().join(',')
       const isBlueskyOwned = isBlueskyOwnedFeed(this.feedUri)
-      const res = await this.agent.app.bsky.feed.getFeed(
+      const data = await this.client.call(
+        app.bsky.feed.getFeed,
         {
           cursor,
           limit,
-          feed: this.feedUri,
+          feed: this.feedUri as AtUriString,
         },
         {
           headers: {
@@ -310,22 +327,24 @@ class MergeFeedSource_Custom extends MergeFeedSource {
       // some custom feeds fail to enforce the pagination limit
       // so we manually truncate here
       // -prf
-      if (limit && res.data.feed.length > limit) {
-        res.data.feed = res.data.feed.slice(0, limit)
-      }
+      let feed: AppBskyFeedDefs.FeedViewPost[] =
+        limit && data.feed.length > limit
+          ? data.feed.slice(0, limit)
+          : data.feed
       // filter out older posts
-      res.data.feed = res.data.feed.filter(
-        post => new Date(post.post.indexedAt) > this.minDate,
-      )
+      feed = feed.filter(post => new Date(post.post.indexedAt) > this.minDate)
       // attach source info
-      for (const post of res.data.feed) {
+      for (const post of feed) {
         // @ts-ignore
         post.__source = this.sourceInfo
       }
-      return res
+      return {
+        cursor: data.cursor,
+        feed,
+      }
     } catch {
       // dont bubble custom-feed errors
-      return {success: false, headers: {}, data: {feed: []}}
+      return null
     }
   }
 }