mirror of https://github.com/joplin/website.git
17 lines
45 KiB
HTML
17 lines
45 KiB
HTML
<!doctype html>
|
||
<html lang="en" dir="ltr" class="docs-wrapper docs-doc-page docs-version-current plugin-docs plugin-id-default docs-doc-id-dev/spec/web_app" data-has-hydrated="false">
|
||
<head>
|
||
<meta charset="UTF-8">
|
||
<meta name="generator" content="Docusaurus v2.4.3">
|
||
<title data-rh="true">Web app | Joplin</title><meta data-rh="true" name="viewport" content="width=device-width,initial-scale=1"><meta data-rh="true" name="twitter:card" content="summary_large_image"><meta data-rh="true" property="og:url" content="https://joplinapp.org/help/dev/spec/web_app"><meta data-rh="true" name="docusaurus_locale" content="en"><meta data-rh="true" name="docsearch:language" content="en"><meta data-rh="true" name="docusaurus_version" content="current"><meta data-rh="true" name="docusaurus_tag" content="docs-default-current"><meta data-rh="true" name="docsearch:version" content="current"><meta data-rh="true" name="docsearch:docusaurus_tag" content="docs-default-current"><meta data-rh="true" property="og:title" content="Web app | Joplin"><meta data-rh="true" name="description" content=":::note This document explains how the Joplin Web App works from a technical perspective. ::: The Joplin Web App is a version of the mobile application that targets web using react-native-web. See ..."><meta data-rh="true" property="og:description" content=":::note This document explains how the Joplin Web App works from a technical perspective. ::: The Joplin Web App is a version of the mobile application that targets web using react-native-web. See ..."><link data-rh="true" rel="icon" href="https://joplinapp.org/favicon.ico"><link data-rh="true" rel="canonical" href="https://joplinapp.org/help/dev/spec/web_app"><link data-rh="true" rel="alternate" href="https://joplinapp.org/help/dev/spec/web_app" hreflang="en"><link data-rh="true" rel="alternate" href="https://joplinapp.org/fr/help/dev/spec/web_app" hreflang="fr"><link data-rh="true" rel="alternate" href="https://joplinapp.org/help/dev/spec/web_app" hreflang="x-default"><link rel="alternate" type="application/rss+xml" href="/news/rss.xml" title="Joplin RSS Feed">
|
||
<link rel="alternate" type="application/atom+xml" href="/news/atom.xml" title="Joplin Atom Feed"><link rel="stylesheet" href="/assets/css/styles.3f0207fa.css">
|
||
<link rel="preload" href="/assets/js/runtime~main.1fb4f966.js" as="script">
|
||
<link rel="preload" href="/assets/js/main.aa9faae4.js" as="script">
|
||
</head>
|
||
<body class="navigation-with-keyboard">
|
||
<script>!function(){function t(t){document.documentElement.setAttribute("data-theme",t)}var e=function(){var t=null;try{t=new URLSearchParams(window.location.search).get("docusaurus-theme")}catch(t){}return t}()||function(){var t=null;try{t=localStorage.getItem("theme")}catch(t){}return t}();t(null!==e?e:"light")}()</script><div id="__docusaurus">
|
||
<div role="region" aria-label="Skip to main content"><a class="skipToContent_fXgn" href="#__docusaurus_skipToContent_fallback">Skip to main content</a></div><nav aria-label="Main" class="navbar navbar--fixed-top"><div class="navbar__inner"><div class="navbar__items"><button aria-label="Toggle navigation bar" aria-expanded="false" class="navbar__toggle clean-btn" type="button"><svg width="30" height="30" viewBox="0 0 30 30" aria-hidden="true"><path stroke="currentColor" stroke-linecap="round" stroke-miterlimit="10" stroke-width="2" d="M4 7h22M4 15h22M4 23h22"></path></svg></button><a href="https://joplinapp.org" target="_self" rel="noopener noreferrer" class="navbar__brand"><div class="navbar__logo"><img src="/images/logo-text-blue.svg" alt="Joplin" class="themedImage_ToTc themedImage--light_HNdA"><img src="/images/logo-text-blue.svg" alt="Joplin" class="themedImage_ToTc themedImage--dark_i4oU"></div><b class="navbar__title text--truncate"></b></a></div><div class="navbar__items navbar__items--right"><a class="navbar__item navbar__link" href="/news">News</a><a aria-current="page" class="navbar__item navbar__link navbar__link--active" href="/help/">Help</a><a href="https://discourse.joplinapp.org" target="_blank" rel="noopener noreferrer" class="navbar__item navbar__link">Forum</a><a href="https://joplinapp.org/plans" target="_self" rel="noopener noreferrer" class="navbar__item navbar__link navbar-custom-buttons plans-button">Joplin Cloud</a><a href="https://joplinapp.org/donate" target="_self" rel="noopener noreferrer" class="navbar__item navbar__link navbar-custom-buttons sponsor-button">♡ Support us</a><div class="navbar__item dropdown dropdown--hoverable dropdown--right"><a href="#" aria-haspopup="true" aria-expanded="false" role="button" class="navbar__link"><svg viewBox="0 0 24 24" width="20" height="20" aria-hidden="true" class="iconLanguage_nlXk"><path fill="currentColor" d="M12.87 15.07l-2.54-2.51.03-.03c1.74-1.94 2.98-4.17 3.71-6.53H17V4h-7V2H8v2H1v1.99h11.17C11.5 7.92 10.44 9.75 9 11.35 8.07 10.32 7.3 9.19 6.69 8h-2c.73 1.63 1.73 3.17 2.98 4.56l-5.09 5.02L4 19l5-5 3.11 3.11.76-2.04zM18.5 10h-2L12 22h2l1.12-3h4.75L21 22h2l-4.5-12zm-2.62 7l1.62-4.33L19.12 17h-3.24z"></path></svg>English</a><ul class="dropdown__menu"><li><a href="/help/dev/spec/web_app" target="_self" rel="noopener noreferrer" class="dropdown__link dropdown__link--active" lang="en">English</a></li><li><a href="/fr/help/dev/spec/web_app" target="_self" rel="noopener noreferrer" class="dropdown__link" lang="fr">Français</a></li></ul></div><div class="toggle_vylO colorModeToggle_DEke"><button class="clean-btn toggleButton_gllP toggleButtonDisabled_aARS" type="button" disabled="" title="Switch between dark and light mode (currently light mode)" aria-label="Switch between dark and light mode (currently light mode)" aria-live="polite"><svg viewBox="0 0 24 24" width="24" height="24" class="lightToggleIcon_pyhR"><path fill="currentColor" d="M12,9c1.65,0,3,1.35,3,3s-1.35,3-3,3s-3-1.35-3-3S10.35,9,12,9 M12,7c-2.76,0-5,2.24-5,5s2.24,5,5,5s5-2.24,5-5 S14.76,7,12,7L12,7z M2,13l2,0c0.55,0,1-0.45,1-1s-0.45-1-1-1l-2,0c-0.55,0-1,0.45-1,1S1.45,13,2,13z M20,13l2,0c0.55,0,1-0.45,1-1 s-0.45-1-1-1l-2,0c-0.55,0-1,0.45-1,1S19.45,13,20,13z M11,2v2c0,0.55,0.45,1,1,1s1-0.45,1-1V2c0-0.55-0.45-1-1-1S11,1.45,11,2z M11,20v2c0,0.55,0.45,1,1,1s1-0.45,1-1v-2c0-0.55-0.45-1-1-1C11.45,19,11,19.45,11,20z M5.99,4.58c-0.39-0.39-1.03-0.39-1.41,0 c-0.39,0.39-0.39,1.03,0,1.41l1.06,1.06c0.39,0.39,1.03,0.39,1.41,0s0.39-1.03,0-1.41L5.99,4.58z M18.36,16.95 c-0.39-0.39-1.03-0.39-1.41,0c-0.39,0.39-0.39,1.03,0,1.41l1.06,1.06c0.39,0.39,1.03,0.39,1.41,0c0.39-0.39,0.39-1.03,0-1.41 L18.36,16.95z M19.42,5.99c0.39-0.39,0.39-1.03,0-1.41c-0.39-0.39-1.03-0.39-1.41,0l-1.06,1.06c-0.39,0.39-0.39,1.03,0,1.41 s1.03,0.39,1.41,0L19.42,5.99z M7.05,18.36c0.39-0.39,0.39-1.03,0-1.41c-0.39-0.39-1.03-0.39-1.41,0l-1.06,1.06 c-0.39,0.39-0.39,1.03,0,1.41s1.03,0.39,1.41,0L7.05,18.36z"></path></svg><svg viewBox="0 0 24 24" width="24" height="24" class="darkToggleIcon_wfgR"><path fill="currentColor" d="M9.37,5.51C9.19,6.15,9.1,6.82,9.1,7.5c0,4.08,3.32,7.4,7.4,7.4c0.68,0,1.35-0.09,1.99-0.27C17.45,17.19,14.93,19,12,19 c-3.86,0-7-3.14-7-7C5,9.07,6.81,6.55,9.37,5.51z M12,3c-4.97,0-9,4.03-9,9s4.03,9,9,9s9-4.03,9-9c0-0.46-0.04-0.92-0.1-1.36 c-0.98,1.37-2.58,2.26-4.4,2.26c-2.98,0-5.4-2.42-5.4-5.4c0-1.81,0.89-3.42,2.26-4.4C12.92,3.04,12.46,3,12,3L12,3z"></path></svg></button></div><div class="searchBox_ZlJk"><div class="navbar__search"><span aria-label="expand searchbar" role="button" class="search-icon" tabindex="0"></span><input type="search" id="search_input_react" placeholder="Loading..." aria-label="Search" class="navbar__search-input search-bar" disabled=""></div></div></div></div><div role="presentation" class="navbar-sidebar__backdrop"></div></nav><div id="__docusaurus_skipToContent_fallback" class="main-wrapper mainWrapper_z2l0 docsWrapper_BCFX"><button aria-label="Scroll back to top" class="clean-btn theme-back-to-top-button backToTopButton_sjWU" type="button"></button><div class="docPage__5DB"><aside class="theme-doc-sidebar-container docSidebarContainer_b6E3"><div class="sidebarViewport_Xe31"><div class="sidebar_njMd"><nav aria-label="Docs sidebar" class="menu thin-scrollbar menu_SIkG"><ul class="theme-doc-sidebar-menu menu__list"><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-1 menu__list-item"><a class="menu__link" href="/help/">What is Joplin?</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-1 menu__list-item"><a class="menu__link" href="/help/install">Installation</a></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist" aria-expanded="false" href="/help/apps/">Using Joplin</a><button aria-label="Toggle the collapsible sidebar category 'Using Joplin'" type="button" class="clean-btn menu__caret"></button></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist" aria-expanded="false" href="/help/api/">Programmatic API</a><button aria-label="Toggle the collapsible sidebar category 'Programmatic API'" type="button" class="clean-btn menu__caret"></button></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--active" aria-expanded="true" href="/help/dev/">Development</a><button aria-label="Toggle the collapsible sidebar category 'Development'" type="button" class="clean-btn menu__caret"></button></div><ul style="display:block;overflow:visible;height:auto" class="menu__list"><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-2 menu__list-item"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret menu__link--active" aria-expanded="true" tabindex="0" href="/help/dev/spec/architecture">Technical specifications</a></div><ul style="display:block;overflow:visible;height:auto" class="menu__list"><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/architecture">Joplin architecture</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/clipper_auth">Clipper authorisation mechanism</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/default_plugins">How to add a new default plugin</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/desktop_styling">Desktop application styling</a></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-3 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist" aria-expanded="false" tabindex="0" href="/help/dev/spec/e2ee/">Encryption</a><button aria-label="Toggle the collapsible sidebar category 'Encryption'" type="button" class="clean-btn menu__caret"></button></div></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/history">Note history</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/interop_with_frontmatter">Markdown with Front Matter Exporter/Importer</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/note_viewer_isolation">Note viewer isolation</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/plugins">Plugin system architecture</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/read_only">Read-only</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/search_sorting">Search Engine</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_debug">Debugging Server project with vscode</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_delta_sync">Joplin Server delta sync</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_file_url_format">Structure of file URLs in Joplin Server</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_items">Joplin Server items</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_sharing">Joplin Server sharing feature</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_sharing_e2ee">Sharing a notebook with E2EE enabled</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/server_user_status">Joplin Server user status</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/sync">Joplin synchronisation</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/sync_lock">Synchronisation locks</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/sync_scroll">Synchronous Scroll</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spec/voice_typing">Voice typing</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-3 menu__list-item"><a class="menu__link menu__link--active" aria-current="page" tabindex="0" href="/help/dev/spec/web_app">Web app</a></li></ul></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-2 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" tabindex="0" href="/help/dev/gsoc/gsoc2020/">Google Summer of Code</a></div></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/BUILD">Building the applications</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/DEPLOY">Deploying Joplin apps and scripts</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/build_troubleshooting">Build troubleshooting</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/coding_style">Coding style</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/localisation">Localisation</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/spellcheck">Spellchecking using CSpell</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="/help/dev/technical_spec">Guide to writing a technical spec</a></li></ul></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="/help/about/changelog/android">About</a></div></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-1 menu__list-item"><a class="menu__link" href="/help/faq">FAQ</a></li></ul></nav></div></div></aside><main class="docMainContainer_gTbr"><div class="container padding-top--md padding-bottom--lg"><div class="row"><div class="col docItemCol_VOVn"><div class="docItemContainer_Djhp"><article><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><h1>Web app</h1><div class="donate-links"><p><a href="https://www.paypal.com/donate/?business=E8JMYD2LQ8MMA&no_recurring=0&item_name=I+rely+on+donations+to+maintain+and+improve+the+Joplin+open+source+project.+Thank+you+for+your+help+-+it+makes+a+difference%21&currency_code=EUR" target="_blank" rel="noopener noreferrer"><img loading="lazy" src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/badges/Donate-PayPal-green.svg" alt="Donate using PayPal" class="img_ev3q"></a> <a href="https://github.com/sponsors/laurent22/" target="_blank" rel="noopener noreferrer"><img loading="lazy" src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/badges/GitHub-Badge.svg" alt="Sponsor on GitHub" class="img_ev3q"></a> <a href="https://www.patreon.com/joplin" target="_blank" rel="noopener noreferrer"><img loading="lazy" src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/badges/Patreon-Badge.svg" alt="Become a patron" class="img_ev3q"></a> <a href="https://joplinapp.org/donate/#donations" target="_blank" rel="noopener noreferrer"><img loading="lazy" src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/badges/Donate-IBAN.svg" alt="Donate using IBAN" class="img_ev3q"></a></p></div><div class="theme-admonition theme-admonition-note alert alert--secondary admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M6.3 5.69a.942.942 0 0 1-.28-.7c0-.28.09-.52.28-.7.19-.18.42-.28.7-.28.28 0 .52.09.7.28.18.19.28.42.28.7 0 .28-.09.52-.28.7a1 1 0 0 1-.7.3c-.28 0-.52-.11-.7-.3zM8 7.99c-.02-.25-.11-.48-.31-.69-.2-.19-.42-.3-.69-.31H6c-.27.02-.48.13-.69.31-.2.2-.3.44-.31.69h1v3c.02.27.11.5.31.69.2.2.42.31.69.31h1c.27 0 .48-.11.69-.31.2-.19.3-.42.31-.69H8V7.98v.01zM7 2.3c-3.14 0-5.7 2.54-5.7 5.68 0 3.14 2.56 5.7 5.7 5.7s5.7-2.55 5.7-5.7c0-3.15-2.56-5.69-5.7-5.69v.01zM7 .98c3.86 0 7 3.14 7 7s-3.14 7-7 7-7-3.12-7-7 3.14-7 7-7z"></path></svg></span>note</div><div class="admonitionContent_S0QG"><p>This document explains how the Joplin Web App works from a technical perspective.</p></div></div><p>The Joplin Web App is a version of the mobile application that targets web using <a href="https://www.npmjs.com/package/react-native-web" target="_blank" rel="noopener noreferrer"><code>react-native-web</code></a>. See <a href="/help/dev/BUILD#web">BUILD.md</a> for information about building the web app.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="file-system">File system<a href="#file-system" class="hash-link" aria-label="Direct link to File system" title="Direct link to File system"></a></h2><p>On web, <code>shim.fsDriver</code> wraps <a href="https://developer.mozilla.org/en-US/docs/Web/API/File_System_API/Origin_private_file_system" target="_blank" rel="noopener noreferrer">the Origin Private File System (OPFS)</a>. As of July 2024, some major browsers (Safari) only provide the synchronous versions of certain operations (e.g. <code>createSyncAccessHandle</code>). These synchronous operations can only be accessed in a web <code>Worker</code>.</p><p>In addition to files stored persistently through the OPFS API, the web <code>fsDriver</code> also supports non-persistent virtual files and access to local user-specified directories.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="virtual-files">Virtual files<a href="#virtual-files" class="hash-link" aria-label="Direct link to Virtual files" title="Direct link to Virtual files"></a></h3><p>In some cases, it doesn't make sense to write temporary files to persistent storage. To support this, <code>fsDriver.web</code> supports creating read-only virtual files with <code>createReadOnlyVirtualFile</code>. These files are stored in local memory and can be accessed using most <code>fsDriver</code> methods.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="local-file-access">Local file access<a href="#local-file-access" class="hash-link" aria-label="Direct link to Local file access" title="Direct link to Local file access"></a></h3><p>In some browsers, it's possible to mount local directories using <code>fsDriver.mountExternalDirectory</code>. This method takes a handle returned by <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/showDirectoryPicker" target="_blank" rel="noopener noreferrer"><code>showDirectoryPicker</code></a>, which, as of 2024, has <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/showDirectoryPicker#browser_compatibility" target="_blank" rel="noopener noreferrer">limited browser support</a>.</p><p>To persist access to external directories, file system handles are stored in <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/indexedDB" target="_blank" rel="noopener noreferrer">an <code>indexedDB</code> database</a>, which supports storing and loading file system handles.</p><p>External files are mounted as subdirectories of the virtual <code>/external/</code> directory.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="database-and-cross-origin-isolation">Database and cross-origin isolation<a href="#database-and-cross-origin-isolation" class="hash-link" aria-label="Direct link to Database and cross-origin isolation" title="Direct link to Database and cross-origin isolation"></a></h2><p>The web app uses <a href="https://github.com/sqlite/sqlite-wasm" target="_blank" rel="noopener noreferrer"><code>@sqlite.org/sqlite-wasm</code></a> for database access.</p><p>To function properly (likely due to use of <code>SharedArrayBuffer</code>), <code>@sqlite.org/sqlite-wasm</code> requires <a href="https://web.dev/articles/coop-coep" target="_blank" rel="noopener noreferrer">cross origin isolation to be enabled</a>. This is done adding certain HTTP headers to responses from the server.</p><p>As of July 2024, the official deployment of the Web App is hosted on GitHub pages, <a href="https://github.com/orgs/community/discussions/13309" target="_blank" rel="noopener noreferrer">which doesn't support serving with these headers</a>. The Web App works around this by providing these headers in a <code>ServiceWorker</code>.</p><p>The Web App's <code>ServiceWorker</code> is a heavily-modified fork of <a href="https://github.com/gzuidhof/coi-serviceworker" target="_blank" rel="noopener noreferrer">the coi-serviceworker project</a>, which enables cross-origin isolation.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="single-instance-lock">Single-instance lock<a href="#single-instance-lock" class="hash-link" aria-label="Direct link to Single-instance lock" title="Direct link to Single-instance lock"></a></h2><p>To prevent data corruption due to out-of-sync state between tabs, the Web App currently only allows one copy of the app to be open at a time.</p><p>This single-instance lock is enforced using a <code>ServiceWorker</code>. If a user attempts to load the Web App in a new tab, the <code>ServiceWorker</code>,</p><ol><li>determines whether the request is for the Web App (see <code>handleRedirects</code> in <code>serviceWorker.ts</code>),</li><li>if so, intercepts the request,</li><li>checks for an already-running copy of the app, and</li><li>if a copy of the app is already running, returns an error page.</li></ol><p>If the <code>ServiceWorker</code> fails to register (and cross-origin isolation is enabled by the server), it may be possible to bypass the <code>ServiceWorker</code>'s single-instance lock. As such, a secondary single-instance lock is also present. This lock attempts to communicate with other open Web Apps using a <code>BroadcastChannel</code>:</p><ul><li>This might succeed even if the original <code>ServiceWorker</code> failed to register.</li><li>This check might incorrectly report that only one app is open if other apps are in a different tab and haven't been used recently.</li></ul><h2 class="anchor anchorWithStickyNavbar_LWe7" id="offline-support">Offline support<a href="#offline-support" class="hash-link" aria-label="Direct link to Offline support" title="Direct link to Offline support"></a></h2><p>The <code>ServiceWorker</code> intercepts and caches responses to requests for certain file types <strong>from the same domain as the web client</strong>. In the future, when equivalent requests fail, the <code>ServiceWorker</code> responds with a cached response.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="webviews">WebViews<a href="#webviews" class="hash-link" aria-label="Direct link to WebViews" title="Direct link to WebViews"></a></h2><p>On all platforms, WebViews that load a local file should use <code>ExtendedWebView</code>. This component uses a different WebView implementation on different platforms:</p><ul><li>Android and iOS use <code>react-native-webview</code>,</li><li>Jest uses <code>JSDOM</code>-based mock, and</li><li>Web uses a sandboxed <code>iframe</code>.<ul><li>As of July 2024, <code>react-native-webview</code> does not support web.</li></ul></li></ul><p>This section summarizes how <code>iframe</code>-based WebViews work on web.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="ipc">IPC<a href="#ipc" class="hash-link" aria-label="Direct link to IPC" title="Direct link to IPC"></a></h3><p>High-level communication can be done with <code>ExtendedWebView</code> using an <code>RNToWebViewMessenger</code> paired with a <code>WebViewToRNMessenger</code>. These <code>RemoteMessenger</code>s expose methods on JavaScript objects to content inside or outside a <code>WebView</code>.</p><p>Although <code>RNToWebViewMessenger</code> and <code>WebViewToRNMessenger</code> wrap <code>.postMessage</code> and <code>.onmessage</code> with a higher-level API, it's still possible to use the lower-level messaging API.</p><h4 class="anchor anchorWithStickyNavbar_LWe7" id="postmessage"><code>.postMessage</code><a href="#postmessage" class="hash-link" aria-label="Direct link to postmessage" title="Direct link to postmessage"></a></h4><p>For compatibility with <code>react-native-webview</code>, <code>ExtendedWebView</code> exposes a <code>ReactNativeWebView</code> global object to content running within the <code>WebView</code>.</p><p>For example, the following syntax can be used to send some <code>message</code> to the <code>ExtendedWebView</code>'s <code>onMessage</code> handler.</p><div class="language-js codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-js codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token maybe-class-name">ReactNativeWebView</span><span class="token punctuation" style="color:#393A34">.</span><span class="token method function property-access" style="color:#d73a49">postMessage</span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">message</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Calls onMessage</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h4 class="anchor anchorWithStickyNavbar_LWe7" id="windowonmessage"><code>window.onmessage</code><a href="#windowonmessage" class="hash-link" aria-label="Direct link to windowonmessage" title="Direct link to windowonmessage"></a></h4><p>Message sent to the WebView using <code>webviewRef.postMessage</code> are received by the global <code>onmessage</code> event. For example,</p><div class="language-tsx codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-tsx codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// ...within some component</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> webViewRef </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token generic-function function" style="color:#d73a49">useRef</span><span class="token generic-function generic class-name operator" style="color:#393A34"><</span><span class="token generic-function generic class-name">WebViewControl</span><span class="token generic-function generic class-name operator" style="color:#393A34">></span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">return</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag class-name" style="color:#00009f">ExtendedWebView</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">webviewInstanceId</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">'</span><span class="token tag attr-value" style="color:#e3116c">test-webview</span><span class="token tag attr-value punctuation" style="color:#393A34">'</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">html</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#393A34">=</span><span class="token tag script language-javascript punctuation" style="color:#393A34">{</span><span class="token tag script language-javascript string" style="color:#e3116c">'some html here'</span><span class="token tag script language-javascript punctuation" style="color:#393A34">}</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">injectedJavaScript</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#393A34">=</span><span class="token tag script language-javascript punctuation" style="color:#393A34">{</span><span class="token tag script language-javascript template-string template-punctuation string" style="color:#e3116c">`</span><span class="token tag script language-javascript template-string string" style="color:#e3116c"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> window.addEventListener('message', event => {</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> if (event.origin === 'react-native') {</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> const messageData = event.data;</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> // ...use event.data...</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> }</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> });</span><br></span><span class="token-line" style="color:#393A34"><span class="token tag script language-javascript template-string string" style="color:#e3116c"> </span><span class="token tag script language-javascript template-string template-punctuation string" style="color:#e3116c">`</span><span class="token tag script language-javascript punctuation" style="color:#393A34">}</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">ref</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#393A34">=</span><span class="token tag script language-javascript punctuation" style="color:#393A34">{</span><span class="token tag script language-javascript" style="color:#00009f">webViewRef</span><span class="token tag script language-javascript punctuation" style="color:#393A34">}</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">onLoadEnd</span><span class="token tag script language-javascript script-punctuation punctuation" style="color:#393A34">=</span><span class="token tag script language-javascript punctuation" style="color:#393A34">{</span><span class="token tag script language-javascript punctuation" style="color:#393A34">(</span><span class="token tag script language-javascript punctuation" style="color:#393A34">)</span><span class="token tag script language-javascript" style="color:#00009f"> </span><span class="token tag script language-javascript arrow operator" style="color:#393A34">=></span><span class="token tag script language-javascript" style="color:#00009f"> webViewRef</span><span class="token tag script language-javascript punctuation" style="color:#393A34">.</span><span class="token tag script language-javascript property-access" style="color:#00009f">current</span><span class="token tag script language-javascript punctuation" style="color:#393A34">.</span><span class="token tag script language-javascript method function property-access" style="color:#d73a49">postMessage</span><span class="token tag script language-javascript punctuation" style="color:#393A34">(</span><span class="token tag script language-javascript string" style="color:#e3116c">'test'</span><span class="token tag script language-javascript punctuation" style="color:#393A34">)</span><span class="token tag script language-javascript punctuation" style="color:#393A34">}</span><span class="token tag" style="color:#00009f"></span><br></span><span class="token-line" style="color:#393A34"><span class="token tag" style="color:#00009f"> </span><span class="token tag punctuation" style="color:#393A34">/></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">)</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="note-viewer">Note viewer<a href="#note-viewer" class="hash-link" aria-label="Direct link to Note viewer" title="Direct link to Note viewer"></a></h2><p>As on Android and iOS, the <code>NoteBodyViewer</code> uses an <code>ExtendedWebView</code> to render and display notes. However, because the Web App uses a virtual file system, extra processing is needed to transfer resources to the WebView.</p><p>For resources, this process might look like this:</p><p>A similar process loads plugin assets (e.g. CSS and fonts used by rendered math).</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="incompatible-libraries">Incompatible libraries<a href="#incompatible-libraries" class="hash-link" aria-label="Direct link to Incompatible libraries" title="Direct link to Incompatible libraries"></a></h2><p>Some libraries are incompatible with <code>react-native-web</code>. There are two or more ways to handle this:</p><ol><li>Use the library only in an Android and iOS-only file. For example, if the library is used in <code>shareImage.ts</code>, create <code>shareImage.web.ts</code> with a web-only implementation. On web, the <code>.web.ts</code> extension is preferred to the <code>.ts</code> extension. On other platforms, this is not the case. As such, on web <code>shareImage.web.ts</code> will be imported, while on other platforms <code>shareImage.ts</code> will be.</li><li>Replace the incompatible library with an empty mock (see <code>web/webpack.config.js</code>). This can be useful if the library is <code>imported</code> by a code that is known to be unreachable on web.</li></ol></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="theme-doc-footer-edit-meta-row row"><div class="col"><a href="https://github.com/laurent22/joplin/tree/dev/readme/dev/spec/web_app.md" target="_blank" rel="noreferrer noopener" class="theme-edit-this-page"><svg fill="currentColor" height="20" width="20" viewBox="0 0 40 40" class="iconEdit_Z9Sw" aria-hidden="true"><g><path d="m34.5 11.7l-3 3.1-6.3-6.3 3.1-3q0.5-0.5 1.2-0.5t1.1 0.5l3.9 3.9q0.5 0.4 0.5 1.1t-0.5 1.2z m-29.5 17.1l18.4-18.5 6.3 6.3-18.4 18.4h-6.3v-6.2z"></path></g></svg>Edit this page</a></div><div class="col lastUpdated_vwxv"></div></div></footer></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/help/dev/spec/voice_typing"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">Voice typing</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/help/dev/gsoc/gsoc2020/"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">Google Summer of Code 2020</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#file-system" class="table-of-contents__link toc-highlight">File system</a><ul><li><a href="#virtual-files" class="table-of-contents__link toc-highlight">Virtual files</a></li><li><a href="#local-file-access" class="table-of-contents__link toc-highlight">Local file access</a></li></ul></li><li><a href="#database-and-cross-origin-isolation" class="table-of-contents__link toc-highlight">Database and cross-origin isolation</a></li><li><a href="#single-instance-lock" class="table-of-contents__link toc-highlight">Single-instance lock</a></li><li><a href="#offline-support" class="table-of-contents__link toc-highlight">Offline support</a></li><li><a href="#webviews" class="table-of-contents__link toc-highlight">WebViews</a><ul><li><a href="#ipc" class="table-of-contents__link toc-highlight">IPC</a></li></ul></li><li><a href="#note-viewer" class="table-of-contents__link toc-highlight">Note viewer</a></li><li><a href="#incompatible-libraries" class="table-of-contents__link toc-highlight">Incompatible libraries</a></li></ul></div></div></div></div></main></div></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://twitter.com/joplinapp" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://www.patreon.com/joplin" target="_blank" rel="noopener noreferrer" class="footer__link-item">Patreon<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://www.linkedin.com/company/joplin" target="_blank" rel="noopener noreferrer" class="footer__link-item">LinkedIn<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://discord.gg/VSj7AFHvpq" target="_blank" rel="noopener noreferrer" class="footer__link-item">Discord<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://mastodon.social/@joplinapp" target="_blank" rel="noopener noreferrer" class="footer__link-item">Mastodon<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://sopuli.xyz/c/joplinapp" target="_blank" rel="noopener noreferrer" class="footer__link-item">Lemmy<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://github.com/laurent22/joplin/" target="_blank" rel="noopener noreferrer" class="footer__link-item">GitHub<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div><div class="col footer__col"><div class="footer__title">Legal</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://joplinapp.org/privacy" target="_blank" rel="noopener noreferrer" class="footer__link-item">Privacy Policy</a></li></ul></div></div><div class="footer__bottom text--center"><div class="footer__copyright">Copyright © 2016-2024 Laurent Cozic</div></div></div></footer></div>
|
||
<script src="/assets/js/runtime~main.1fb4f966.js"></script>
|
||
<script src="/assets/js/main.aa9faae4.js"></script>
|
||
</body>
|
||
</html> |