Clean up projections

packages/client/src/plugins/base.ts

@@ -17,14 +17,19 @@ export type Projection<T> = {
 
 export const projection = <T>($: Readable<T>, get = getter($)) => ({$, get})
 
+/**
+ * Build a `Projection` derived from another `Projection`: re-read `src`
+ * reactively via `.$` or synchronously via `.get()`.
+ */
+export const projectFrom = <S, U>(src: Projection<S>, read: ($: S) => U): Projection<U> =>
+  projection(derived(src.$, read), () => read(src.get()))
+
 /**
  * Synchronous read access to a keyed collection's current value. Shared by
  * collections that own a map (`MapPlugin`) and those that are read-only views
  * over the repository (`DerivedPlugin`).
  */
 export interface ReadableMap<T> {
-  keys(): IterableIterator<string>
-  values(): IterableIterator<T>
   get(key: string): Maybe<T>
 }
 
@@ -81,12 +86,11 @@ export class MapPlugin<T> implements Mappable<T>, Derivable<T> {
     this.one = makeDeriveItem(this.store)
   }
 
-  keys = () => this.index.get().keys()
-
-  values = () => this.index.get().values()
-
   get = (key: string) => this.index.get().get(key)
 
+  project = <U>(key: string, read: (item: Maybe<T>) => U): Projection<U> =>
+    projection(derived(this.one(key), read), () => read(this.get(key)))
+
   set = (key: string, value: T) => {
     this.store.update($items => {
       $items.set(key, value)
@@ -207,16 +211,8 @@ export abstract class DerivedPlugin<T> implements ReadableMap<T>, Loadable<T>, D
     this.one = makeDeriveItem(index, this.load)
   }
 
-  keys = () => this.index.get().keys()
-
-  values = () => this.index.get().values()
-
   get = (key: string) => this.index.get().get(key)
 
-  /**
-   * Build a per-key `Projection` over this collection: snapshot synchronously
-   * with `.get()`, or subscribe via `.$` (which lazily loads the key).
-   */
-  protected project = <U>(key: string, read: (item: Maybe<T>) => U): Projection<U> =>
+  project = <U>(key: string, read: (item: Maybe<T>) => U): Projection<U> =>
     projection(derived(this.one(key), read), () => read(this.get(key)))
 }

packages/client/src/plugins/network.ts

@@ -11,7 +11,8 @@ import type {
   PullOptions,
   PushOptions,
 } from "@welshman/net"
-import {Router, addMinimalFallbacks} from "./router.js"
+import {addMinimalFallbacks} from "@welshman/router"
+import {Router} from "./router.js"
 import {RelayLists} from "./relayLists.js"
 import type {IClient} from "../client.js"
 

packages/client/src/plugins/relayLists.ts

@@ -14,7 +14,8 @@ import {
 import type {TrustedEvent, PublishedList} from "@welshman/util"
 import {DerivedPlugin} from "./base.js"
 import type {Projection} from "./base.js"
-import {Router, addMinimalFallbacks} from "./router.js"
+import {addMinimalFallbacks} from "@welshman/router"
+import {Router} from "./router.js"
 import {Network} from "./network.js"
 import {User} from "../user.js"
 import {Thunks} from "./thunk.js"

packages/client/src/plugins/relays.ts

@@ -1,9 +1,8 @@
-import {derived} from "svelte/store"
 import {fetchJson} from "@welshman/lib"
 import type {Maybe} from "@welshman/lib"
 import {displayRelayUrl, displayRelayProfile} from "@welshman/util"
 import type {RelayProfile} from "@welshman/util"
-import {LoadableMapPlugin, projection} from "./base.js"
+import {LoadableMapPlugin} from "./base.js"
 import type {Projection} from "./base.js"
 
 /**
@@ -37,11 +36,8 @@ export class Relays extends LoadableMapPlugin<RelayProfile> {
     }
   }
 
-  display = (url: string): Projection<string> => {
-    const read = ($relay: Maybe<RelayProfile>) => displayRelayProfile($relay, displayRelayUrl(url))
-
-    return projection(derived(this.one(url), read), () => read(this.get(url)))
-  }
+  display = (url: string): Projection<string> =>
+    this.project(url, $relay => displayRelayProfile($relay, displayRelayUrl(url)))
 
   hasNegentropy = async (url: string) => {
     const relay = await this.load(url)

packages/client/src/plugins/thunk.ts

@@ -15,7 +15,8 @@ import {PublishStatus, PublishResult, PublishOptions, PublishResultsByRelay} fro
 import {Nip01Signer, Nip59} from "@welshman/signer"
 import type {IClient} from "../client.js"
 import {Network} from "./network.js"
-import {Router, addMinimalFallbacks} from "./router.js"
+import {addMinimalFallbacks} from "@welshman/router"
+import {Router} from "./router.js"
 import {User} from "../user.js"
 
 export type ThunkOptions = Override<

packages/client/src/plugins/wot.ts

@@ -3,7 +3,7 @@ import {max, throttle, addToMapKey, inc, dec} from "@welshman/lib"
 import {getListTags, getPubkeyTagValues} from "@welshman/util"
 import type {List} from "@welshman/util"
 import type {IClient} from "../client.js"
-import {projection} from "./base.js"
+import {projection, projectFrom} from "./base.js"
 import type {Projection} from "./base.js"
 import {FollowLists} from "./follows.js"
 import {MuteLists} from "./mutes.js"
@@ -95,24 +95,14 @@ export class Wot {
     this.max = projection(maxStore)
   }
 
-  follows = (pubkey: string): Projection<string[]> => {
-    const read = ($lists: ReadonlyMap<string, List>) => listPubkeys($lists.get(pubkey))
+  follows = (pubkey: string): Projection<string[]> =>
+    projectFrom(this.ctx.use(FollowLists).index, $lists => listPubkeys($lists.get(pubkey)))
 
-    return projection(derived(this.ctx.use(FollowLists).index.$, read), () =>
-      read(this.ctx.use(FollowLists).index.get()),
-    )
-  }
+  mutes = (pubkey: string): Projection<string[]> =>
+    projectFrom(this.ctx.use(MuteLists).index, $lists => listPubkeys($lists.get(pubkey)))
 
-  mutes = (pubkey: string): Projection<string[]> => {
-    const read = ($lists: ReadonlyMap<string, List>) => listPubkeys($lists.get(pubkey))
-
-    return projection(derived(this.ctx.use(MuteLists).index.$, read), () =>
-      read(this.ctx.use(MuteLists).index.get()),
-    )
-  }
-
-  network = (pubkey: string): Projection<string[]> => {
-    const read = ($lists: ReadonlyMap<string, List>) => {
+  network = (pubkey: string): Projection<string[]> =>
+    projectFrom(this.ctx.use(FollowLists).index, $lists => {
       const pubkeys = new Set(listPubkeys($lists.get(pubkey)))
       const network = new Set<string>()
 
@@ -125,39 +115,20 @@ export class Wot {
       }
 
       return Array.from(network)
-    }
+    })
 
-    return projection(derived(this.ctx.use(FollowLists).index.$, read), () =>
-      read(this.ctx.use(FollowLists).index.get()),
-    )
-  }
+  followers = (pubkey: string): Projection<string[]> =>
+    projectFrom(this.followersByPubkey, $followers => Array.from($followers.get(pubkey) || []))
 
-  followers = (pubkey: string): Projection<string[]> => {
-    const read = ($followers: ReadonlyMap<string, Set<string>>) =>
-      Array.from($followers.get(pubkey) || [])
+  muters = (pubkey: string): Projection<string[]> =>
+    projectFrom(this.mutersByPubkey, $muters => Array.from($muters.get(pubkey) || []))
 
-    return projection(derived(this.followersByPubkey.$, read), () =>
-      read(this.followersByPubkey.get()),
-    )
-  }
-
-  muters = (pubkey: string): Projection<string[]> => {
-    const read = ($muters: ReadonlyMap<string, Set<string>>) =>
-      Array.from($muters.get(pubkey) || [])
-
-    return projection(derived(this.mutersByPubkey.$, read), () => read(this.mutersByPubkey.get()))
-  }
-
-  followsWhoFollow = (pubkey: string, target: string): Projection<string[]> => {
-    const read = ($lists: ReadonlyMap<string, List>) =>
+  followsWhoFollow = (pubkey: string, target: string): Projection<string[]> =>
+    projectFrom(this.ctx.use(FollowLists).index, $lists =>
       listPubkeys($lists.get(pubkey)).filter(other =>
         listPubkeys($lists.get(other)).includes(target),
-      )
-
-    return projection(derived(this.ctx.use(FollowLists).index.$, read), () =>
-      read(this.ctx.use(FollowLists).index.get()),
+      ),
     )
-  }
 
   followsWhoMute = (pubkey: string, target: string): Projection<string[]> => {
     const read = ($follows: ReadonlyMap<string, List>, $mutes: ReadonlyMap<string, List>) =>