Centralized fetch methods

material/assets/manifest.json

@@ -1,6 +1,6 @@
 {
-  "assets/javascripts/bundle.js": "assets/javascripts/bundle.48bdffa8.min.js",
-  "assets/javascripts/bundle.js.map": "assets/javascripts/bundle.48bdffa8.min.js.map",
+  "assets/javascripts/bundle.js": "assets/javascripts/bundle.1ed0f3ef.min.js",
+  "assets/javascripts/bundle.js.map": "assets/javascripts/bundle.1ed0f3ef.min.js.map",
   "assets/javascripts/vendor.js": "assets/javascripts/vendor.250c9a34.min.js",
   "assets/javascripts/vendor.js.map": "assets/javascripts/vendor.250c9a34.min.js.map",
   "assets/javascripts/worker/search.js": "assets/javascripts/worker/search.b9424174.min.js",

material/base.html

@@ -217,7 +217,7 @@
     {% endblock %}
     {% block scripts %}
       <script src="{{ 'assets/javascripts/vendor.250c9a34.min.js' | url }}"></script>
-      <script src="{{ 'assets/javascripts/bundle.48bdffa8.min.js' | url }}"></script>
+      <script src="{{ 'assets/javascripts/bundle.1ed0f3ef.min.js' | url }}"></script>
       {% for path in config["extra_javascript"] %}
         <script src="{{ path | url }}"></script>
       {% endfor %}

src/assets/javascripts/_/index.ts

@@ -29,7 +29,7 @@ import { getElementOrThrow, getLocation } from "~/browser"
 /**
  * Feature flag
  */
-export type Feature =
+export type Flag =
   | "header.autohide"                  /* Hide header */
   | "navigation.tabs"                  /* Tabs navigation */
   | "navigation.instant"               /* Instant loading */
@@ -66,7 +66,7 @@ export type Translations = Record<Translation, string>
  */
 export interface Config {
   base: string                         /* Base URL */
-  features: Feature[]                  /* Feature flags */
+  features: Flag[]                     /* Feature flags */
   translations: Translations           /* Translations */
   search: string                       /* Search worker URL */
 }
@@ -78,7 +78,8 @@ export interface Config {
 /**
  * Retrieve global configuration and make base URL absolute
  */
-const config: Config = JSON.parse(getElementOrThrow("#__config").textContent!)
+const script = getElementOrThrow("#__config")
+const config: Config = JSON.parse(script.textContent!)
 config.base = new URL(config.base, getLocation())
   .toString()
   .replace(/\/$/, "")
@@ -97,14 +98,14 @@ export function configuration(): Config {
 }
 
 /**
- * Check whether a feature is enabled
+ * Check whether a feature flag is enabled
  *
- * @param feature - Feature
+ * @param flag - Feature flag
  *
  * @returns Test result
  */
-export function flag(feature: Feature): boolean {
-  return config.features.includes(feature)
+export function feature(flag: Flag): boolean {
+  return config.features.includes(flag)
 }
 
 /**
@@ -118,9 +119,6 @@ export function flag(feature: Feature): boolean {
 export function translation(
   key: Translation, value?: string | number
 ): string {
-  if (typeof config.translations[key] === "undefined") {
-    throw new ReferenceError(`Invalid translation: ${key}`)
-  }
   return typeof value !== "undefined"
     ? config.translations[key].replace("#", value.toString())
     : config.translations[key]

src/assets/javascripts/browser/element/_/index.ts

@@ -40,7 +40,7 @@ export function getElement<T extends keyof HTMLElementTagNameMap>(
 
 export function getElement<T extends HTMLElement>(
   selector: string, node?: ParentNode
-): T
+): T | undefined
 
 export function getElement<T extends HTMLElement>(
   selector: string, node: ParentNode = document

src/assets/javascripts/browser/fetch/index.ts

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2016-2020 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import { Observable, from } from "rxjs"
+import {
+  filter,
+  map,
+  shareReplay,
+  switchMap
+} from "rxjs/operators"
+
+/* ----------------------------------------------------------------------------
+ * Data
+ * ------------------------------------------------------------------------- */
+
+/**
+ * XML parser
+ */
+const dom = new DOMParser()
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Fetch given URL as JSON
+ *
+ * @template T - Data type
+ *
+ * @param url - Request URL
+ * @param options - Request options
+ *
+ * @returns Data observable
+ */
+export function fetchJSON<T>(
+  url: string, options: RequestInit = { credentials: "same-origin" }
+): Observable<T> {
+  return from(fetch(url, options))
+    .pipe(
+      filter(res => res.status === 200),
+      switchMap(res => res.json()),
+      shareReplay(1)
+    )
+}
+
+/**
+ * Fetch given URL as XML
+ *
+ * @param url - Request URL
+ * @param options - Request options
+ *
+ * @returns Data observable
+ */
+export function fetchXML(
+  url: string, options: RequestInit = { credentials: "same-origin" }
+): Observable<Document> {
+  return from(fetch(url, options))
+    .pipe(
+      filter(res => res.status === 200),
+      switchMap(res => res.json()),
+      map(res => dom.parseFromString(res, "text/xml")),
+      shareReplay(1)
+    )
+}

src/assets/javascripts/browser/index.ts

@@ -22,6 +22,7 @@
 
 export * from "./document"
 export * from "./element"
+export * from "./fetch"
 export * from "./keyboard"
 export * from "./location"
 export * from "./media"

src/assets/javascripts/components/header/title/index.ts

@@ -20,7 +20,7 @@
  * IN THE SOFTWARE.
  */
 
-import { Observable, Subject, animationFrameScheduler } from "rxjs"
+import { NEVER, Observable, Subject, animationFrameScheduler } from "rxjs"
 import {
   distinctUntilKeyChanged,
   finalize,
@@ -35,7 +35,7 @@ import {
 } from "~/actions"
 import {
   Viewport,
-  getElementOrThrow,
+  getElement,
   getElementSize,
   watchViewportAt
 } from "~/browser"
@@ -124,8 +124,12 @@ export function mountHeaderTitle(
           resetHeaderTitleState(el)
       })
 
+  /* Obtain headline, if any */
+  const headline = getElement<HTMLHeadingElement>("article h1")
+  if (typeof headline === "undefined")
+    return NEVER
+
   /* Create and return component */
-  const headline = getElementOrThrow<HTMLHeadingElement>("article h1")
   return watchHeaderTitle(headline, options)
     .pipe(
       tap(internal$),

src/assets/javascripts/components/search/_/index.ts

@@ -24,8 +24,9 @@ import { Observable, merge } from "rxjs"
 import { filter, sample, take } from "rxjs/operators"
 
 import { configuration } from "~/_"
-import { getElementOrThrow } from "~/browser"
+import { fetchJSON, getElementOrThrow } from "~/browser"
 import {
+  SearchIndex,
   isSearchQueryMessage,
   isSearchReadyMessage,
   setupSearchWorker
@@ -58,8 +59,7 @@ export type Search =
  * @returns Promise resolving with search index
  */
 function fetchSearchIndex(url: string) {
-  return __search?.index || fetch(url, { credentials: "same-origin" })
-    .then(res => res.json())
+  return __search?.index || fetchJSON<SearchIndex>(url)
 }
 
 /* ----------------------------------------------------------------------------
@@ -91,14 +91,18 @@ export function mountSearch(
     )
       .subscribe(tx$.next.bind(tx$))
 
-  /* Obtain search query and result elements */
-  const query  = getElementOrThrow("[data-md-component=search-query]", el)
-  const result = getElementOrThrow("[data-md-component=search-result]", el)
+  /* Mount search query component */
+  const query$ = mountSearchQuery(
+    getElementOrThrow("[data-md-component=search-query]", el),
+    worker
+  )
 
-  /* Create and return component */
-  const query$ = mountSearchQuery(query as HTMLInputElement, worker)
+  /* Mount search result and return component */
   return merge(
     query$,
-    mountSearchResult(result, worker, { query$ })
+    mountSearchResult(
+      getElementOrThrow("[data-md-component=search-result]", el),
+      worker, { query$ }
+    )
   )
 }

src/assets/javascripts/components/search/result/index.ts

@@ -88,7 +88,7 @@ export function mountSearchResult(
   const internal$ = new Subject<SearchResult>()
 
   /* Update search result metadata */
-  const meta = getElementOrThrow(":first-child", el)
+  const meta = getElementOrThrow(":scope > :first-child", el)
   internal$
     .pipe(
       withLatestFrom(query$)
@@ -101,7 +101,7 @@ export function mountSearchResult(
       })
 
   /* Update search result list */
-  const list = getElementOrThrow(":last-child", el)
+  const list = getElementOrThrow(":scope > :last-child", el)
   internal$
     .subscribe(({ data }) => {
       resetSearchResultList(list)

src/assets/javascripts/components/source/facts/github/index.ts

@@ -21,14 +21,10 @@
  */
 
 import { Repo, User } from "github-types"
-import { Observable, from } from "rxjs"
-import {
-  defaultIfEmpty,
-  filter,
-  map,
-  switchMap
-} from "rxjs/operators"
+import { Observable } from "rxjs"
+import { defaultIfEmpty, map } from "rxjs/operators"
 
+import { fetchJSON } from "~/browser"
 import { round } from "~/utilities"
 
 import { SourceFacts } from "../_"
@@ -51,10 +47,8 @@ export function fetchSourceFactsFromGitHub(
   const url = typeof repo !== "undefined"
     ? `https://api.github.com/repos/${user}/${repo}`
     : `https://api.github.com/users/${user}`
-  return from(fetch(url))
+  return fetchJSON<Repo & User>(url)
     .pipe(
-      filter(res => res.status === 200),
-      switchMap(res => res.json()),
       map(data => {
 
         /* GitHub repository */

src/assets/javascripts/components/source/facts/gitlab/index.ts

@@ -21,14 +21,10 @@
  */
 
 import { ProjectSchema } from "gitlab"
-import { Observable, from } from "rxjs"
-import {
-  defaultIfEmpty,
-  filter,
-  map,
-  switchMap
-} from "rxjs/operators"
+import { Observable } from "rxjs"
+import { defaultIfEmpty, map } from "rxjs/operators"
 
+import { fetchJSON } from "~/browser"
 import { round } from "~/utilities"
 
 import { SourceFacts } from "../_"
@@ -49,11 +45,9 @@ export function fetchSourceFactsFromGitLab(
   base: string, project: string
 ): Observable<SourceFacts> {
   const url = `https://${base}/api/v4/projects/${encodeURIComponent(project)}`
-  return from(fetch(url))
+  return fetchJSON<ProjectSchema>(url)
     .pipe(
-      filter(res => res.status === 200),
-      switchMap(res => res.json()),
-      map(({ star_count, forks_count }: ProjectSchema) => ([
+      map(({ star_count, forks_count }) => ([
         `${round(star_count)} Stars`,
         `${round(forks_count)} Forks`
       ])),

src/assets/javascripts/index.ts

@@ -24,7 +24,6 @@ import "focus-visible"
 import { NEVER, Observable, Subject, merge } from "rxjs"
 import { switchMap } from "rxjs/operators"
 
-import { translation } from "./_"
 import {
   getElementOrThrow,
   getElements,
@@ -76,8 +75,7 @@ const main$   = watchMain(main, { header$, viewport$ })
 
 /* Setup Clipboard.js integration */
 const message$ = new Subject<string>()
-setupClipboardJS()
-  .subscribe(() => message$.next(translation("clipboard.copied")))
+setupClipboardJS({ message$ })
 
 // TODO: watchElements + general mount function that takes a factory...
 // + a toggle function (optionally)

src/assets/javascripts/integrations/clipboard/index.ts

@@ -21,8 +21,20 @@
  */
 
 import ClipboardJS from "clipboard"
-import { NEVER, Observable } from "rxjs"
-import { share } from "rxjs/operators"
+import { Observable, Subject } from "rxjs"
+
+import { translation } from "~/_"
+
+/* ----------------------------------------------------------------------------
+ * Helper types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Setup options
+ */
+interface SetupOptions {
+  message$: Subject<string>            /* Message subject */
+}
 
 /* ----------------------------------------------------------------------------
  * Functions
@@ -31,18 +43,16 @@ import { share } from "rxjs/operators"
 /**
  * Set up Clipboard.js integration
  *
- * @returns Clipboard.js event observable
+ * @param options - Options
  */
-export function setupClipboardJS(): Observable<ClipboardJS.Event> {
-  if (!ClipboardJS.isSupported())
-    return NEVER
-
-  /* Initialize Clipboard.js */
-  return new Observable<ClipboardJS.Event>(subscriber => {
+export function setupClipboardJS(
+  { message$ }: SetupOptions
+): void {
+  if (!ClipboardJS.isSupported()) {
+    new Observable<ClipboardJS.Event>(subscriber => {
       new ClipboardJS("[data-clipboard-target], [data-clipboard-text]")
         .on("success", ev => subscriber.next(ev))
     })
-    .pipe(
-      share()
-    )
+      .subscribe(() => message$.next(translation("clipboard.copied")))
+  }
 }

src/assets/javascripts/integrations/index.ts

@@ -21,4 +21,5 @@
  */
 
 export * from "./clipboard"
+export * from "./instant"
 export * from "./search"

src/assets/javascripts/integrations/instant/.eslintrc

@@ -0,0 +1,5 @@
+{
+  "rules": {
+    "no-self-assign": "off"
+  }
+}

src/assets/javascripts/integrations/instant/index.ts

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2016-2020 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import { Observable, Subject, fromEvent } from "rxjs"
+
+import { Viewport, ViewportOffset, getElement } from "~/browser"
+
+/* ----------------------------------------------------------------------------
+ * Types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * History state
+ */
+export interface HistoryState {
+  url: URL                             /* State URL */
+  offset?: ViewportOffset              /* State viewport offset */
+}
+
+/* ----------------------------------------------------------------------------
+ * Helper types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Setup options
+ */
+interface SetupOptions {
+  document$: Subject<Document>         /* Document subject */
+  location$: Subject<URL>              /* Location subject */
+  viewport$: Observable<Viewport>      /* Viewport observable */
+}
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Set up instant loading
+ *
+ * When fetching, theoretically, we could use `responseType: "document"`, but
+ * since all MkDocs links are relative, we need to make sure that the current
+ * location matches the document we just loaded. Otherwise any relative links
+ * in the document could use the old location.
+ *
+ * This is the reason why we need to synchronize history events and the process
+ * of fetching the document for navigation changes (except `popstate` events):
+ *
+ * 1. Fetch document via `XMLHTTPRequest`
+ * 2. Set new location via `history.pushState`
+ * 3. Parse and emit fetched document
+ *
+ * For `popstate` events, we must not use `history.pushState`, or the forward
+ * history will be irreversibly overwritten. In case the request fails, the
+ * location change is dispatched regularly.
+ *
+ * @param urls - URLs to load with XHR
+ * @param options - Options
+ */
+export function setupInstantLoading(
+  urls: string[], { document$, location$, viewport$ }: SetupOptions
+): void {
+  if (location.protocol === "file:")
+    return
+
+  /* Disable automatic scroll restoration */
+  if ("scrollRestoration" in history) {
+    history.scrollRestoration = "manual"
+
+    /* Hack: ensure that reloads restore viewport offset */
+    fromEvent(window, "beforeunload")
+      .subscribe(() => {
+        history.scrollRestoration = "auto"
+      })
+  }
+
+  /* Hack: ensure absolute favicon link to omit 404s when switching */
+  const favicon = getElement<HTMLLinkElement>("link[rel='shortcut icon']")
+  if (typeof favicon !== "undefined")
+    favicon.href = favicon.href
+
+  // eslint-disable-next-line
+  console.log(urls, document$, location$, viewport$)
+}

src/assets/javascripts/integrations/search/worker/_/index.ts

@@ -20,8 +20,8 @@
  * IN THE SOFTWARE.
  */
 
-import { Subject, asyncScheduler, from } from "rxjs"
-import { delay, map, observeOn, share } from "rxjs/operators"
+import { ObservableInput, Subject, from } from "rxjs"
+import { map, share } from "rxjs/operators"
 
 import { configuration, translation } from "~/_"
 import { WorkerHandler, watchWorker } from "~/browser"
@@ -82,19 +82,19 @@ function setupSearchIndex(
  * ------------------------------------------------------------------------- */
 
 /**
- * Set up search web worker
+ * Set up search worker
  *
  * This function will create a web worker to set up and query the search index
  * which is done using `lunr`. The index must be passed as an observable to
  * enable hacks like _localsearch_ via search index embedding as JSON.
  *
  * @param url - Worker URL
- * @param index - Promise resolving with search index
+ * @param index - Search index observable input
  *
  * @returns Search worker
  */
 export function setupSearchWorker(
-  url: string, index: Promise<SearchIndex>
+  url: string, index: ObservableInput<SearchIndex>
 ): SearchWorker {
   const config = configuration()
   const worker = new Worker(url)