media_repository.html 25 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249
  1. <!DOCTYPE HTML>
  2. <html lang="en" class="sidebar-visible no-js light">
  3. <head>
  4. <!-- Book generated using mdBook -->
  5. <meta charset="UTF-8">
  6. <title>Media Repository - Synapse</title>
  7. <!-- Custom HTML head -->
  8. <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  9. <meta name="description" content="">
  10. <meta name="viewport" content="width=device-width, initial-scale=1">
  11. <meta name="theme-color" content="#ffffff" />
  12. <link rel="icon" href="favicon.svg">
  13. <link rel="shortcut icon" href="favicon.png">
  14. <link rel="stylesheet" href="css/variables.css">
  15. <link rel="stylesheet" href="css/general.css">
  16. <link rel="stylesheet" href="css/chrome.css">
  17. <link rel="stylesheet" href="css/print.css" media="print">
  18. <!-- Fonts -->
  19. <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
  20. <link rel="stylesheet" href="fonts/fonts.css">
  21. <!-- Highlight.js Stylesheets -->
  22. <link rel="stylesheet" href="highlight.css">
  23. <link rel="stylesheet" href="tomorrow-night.css">
  24. <link rel="stylesheet" href="ayu-highlight.css">
  25. <!-- Custom theme stylesheets -->
  26. <link rel="stylesheet" href="docs/website_files/table-of-contents.css">
  27. <link rel="stylesheet" href="docs/website_files/remove-nav-buttons.css">
  28. <link rel="stylesheet" href="docs/website_files/indent-section-headers.css">
  29. </head>
  30. <body>
  31. <!-- Provide site root to javascript -->
  32. <script type="text/javascript">
  33. var path_to_root = "";
  34. var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
  35. </script>
  36. <!-- Work around some values being stored in localStorage wrapped in quotes -->
  37. <script type="text/javascript">
  38. try {
  39. var theme = localStorage.getItem('mdbook-theme');
  40. var sidebar = localStorage.getItem('mdbook-sidebar');
  41. if (theme.startsWith('"') && theme.endsWith('"')) {
  42. localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
  43. }
  44. if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
  45. localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
  46. }
  47. } catch (e) { }
  48. </script>
  49. <!-- Set the theme before any content is loaded, prevents flash -->
  50. <script type="text/javascript">
  51. var theme;
  52. try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
  53. if (theme === null || theme === undefined) { theme = default_theme; }
  54. var html = document.querySelector('html');
  55. html.classList.remove('no-js')
  56. html.classList.remove('light')
  57. html.classList.add(theme);
  58. html.classList.add('js');
  59. </script>
  60. <!-- Hide / unhide sidebar before it is displayed -->
  61. <script type="text/javascript">
  62. var html = document.querySelector('html');
  63. var sidebar = 'hidden';
  64. if (document.body.clientWidth >= 1080) {
  65. try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
  66. sidebar = sidebar || 'visible';
  67. }
  68. html.classList.remove('sidebar-visible');
  69. html.classList.add("sidebar-" + sidebar);
  70. </script>
  71. <nav id="sidebar" class="sidebar" aria-label="Table of contents">
  72. <div class="sidebar-scrollbox">
  73. <ol class="chapter"><li class="chapter-item expanded affix "><li class="part-title">Introduction</li><li class="chapter-item expanded "><a href="welcome_and_overview.html">Welcome and Overview</a></li><li class="chapter-item expanded affix "><li class="part-title">Setup</li><li class="chapter-item expanded "><a href="setup/installation.html">Installation</a></li><li class="chapter-item expanded "><a href="postgres.html">Using Postgres</a></li><li class="chapter-item expanded "><a href="reverse_proxy.html">Configuring a Reverse Proxy</a></li><li class="chapter-item expanded "><a href="setup/forward_proxy.html">Configuring a Forward/Outbound Proxy</a></li><li class="chapter-item expanded "><a href="turn-howto.html">Configuring a Turn Server</a></li><li class="chapter-item expanded "><a href="delegate.html">Delegation</a></li><li class="chapter-item expanded affix "><li class="part-title">Upgrading</li><li class="chapter-item expanded "><a href="upgrade.html">Upgrading between Synapse Versions</a></li><li class="chapter-item expanded affix "><li class="part-title">Usage</li><li class="chapter-item expanded "><a href="federate.html">Federation</a></li><li class="chapter-item expanded "><a href="usage/configuration/index.html">Configuration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="usage/configuration/config_documentation.html">Configuration Manual</a></li><li class="chapter-item expanded "><a href="usage/configuration/homeserver_sample_config.html">Homeserver Sample Config File</a></li><li class="chapter-item expanded "><a href="usage/configuration/logging_sample_config.html">Logging Sample Config File</a></li><li class="chapter-item expanded "><a href="structured_logging.html">Structured Logging</a></li><li class="chapter-item expanded "><a href="templates.html">Templates</a></li><li class="chapter-item expanded "><a href="usage/configuration/user_authentication/index.html">User Authentication</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="usage/configuration/user_authentication/single_sign_on/index.html">Single-Sign On</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="openid.html">OpenID Connect</a></li><li class="chapter-item expanded "><a href="usage/configuration/user_authentication/single_sign_on/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="usage/configuration/user_authentication/single_sign_on/cas.html">CAS</a></li><li class="chapter-item expanded "><a href="sso_mapping_providers.html">SSO Mapping Providers</a></li></ol></li><li class="chapter-item expanded "><a href="password_auth_providers.html">Password Auth Providers</a></li><li class="chapter-item expanded "><a href="jwt.html">JSON Web Tokens</a></li><li class="chapter-item expanded "><a href="usage/configuration/user_authentication/refresh_tokens.html">Refresh Tokens</a></li></ol></li><li class="chapter-item expanded "><a href="CAPTCHA_SETUP.html">Registration Captcha</a></li><li class="chapter-item expanded "><a href="application_services.html">Application Services</a></li><li class="chapter-item expanded "><a href="server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="consent_tracking.html">Consent Tracking</a></li><li class="chapter-item expanded "><a href="user_directory.html">User Directory</a></li><li class="chapter-item expanded "><a href="message_retention_policies.html">Message Retention Policies</a></li><li class="chapter-item expanded "><a href="modules/index.html">Pluggable Modules</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="modules/writing_a_module.html">Writing a module</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="modules/spam_checker_callbacks.html">Spam checker callbacks</a></li><li class="chapter-item expanded "><a href="modules/third_party_rules_callbacks.html">Third-party rules callbacks</a></li><li class="chapter-item expanded "><a href="modules/presence_router_callbacks.html">Presence router callbacks</a></li><li class="chapter-item expanded "><a href="modules/account_validity_callbacks.html">Account validity callbacks</a></li><li class="chapter-item expanded "><a href="modules/password_auth_provider_callbacks.html">Password auth provider callbacks</a></li><li class="chapter-item expanded "><a href="modules/background_update_controller_callbacks.html">Background update controller callbacks</a></li><li class="chapter-item expanded "><a href="modules/account_data_callbacks.html">Account data callbacks</a></li><li class="chapter-item expanded "><a href="modules/porting_legacy_module.html">Porting a legacy module to the new interface</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="workers.html">Workers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="synctl_workers.html">Using synctl with Workers</a></li><li class="chapter-item expanded "><a href="systemd-with-workers/index.html">Systemd</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="usage/administration/index.html">Administration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="usage/administration/admin_api/index.html">Admin API</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="admin_api/account_validity.html">Account Validity</a></li><li class="chapter-item expanded "><a href="usage/administration/admin_api/background_updates.html">Background Updates</a></li><li class="chapter-item expanded "><a href="admin_api/event_reports.html">Event Reports</a></li><li class="chapter-item expanded "><a href="admin_api/media_admin_api.html">Media</a></li><li class="chapter-item expanded "><a href="admin_api/purge_history_api.html">Purge History</a></li><li class="chapter-item expanded "><a href="admin_api/register_api.html">Register Users</a></li><li class="chapter-item expanded "><a href="usage/administration/admin_api/registration_tokens.html">Registration Tokens</a></li><li class="chapter-item expanded "><a href="admin_api/room_membership.html">Manipulate Room Membership</a></li><li class="chapter-item expanded "><a href="admin_api/rooms.html">Rooms</a></li><li class="chapter-item expanded "><a href="admin_api/server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="admin_api/statistics.html">Statistics</a></li><li class="chapter-item expanded "><a href="admin_api/user_admin_api.html">Users</a></li><li class="chapter-item expanded "><a href="admin_api/version_api.html">Server Version</a></li><li class="chapter-item expanded "><a href="usage/administration/admin_api/federation.html">Federation</a></li></ol></li><li class="chapter-item expanded "><a href="manhole.html">Manhole</a></li><li class="chapter-item expanded "><a href="metrics-howto.html">Monitoring</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="usage/administration/monitoring/reporting_homeserver_usage_statistics.html">Reporting Homeserver Usage Statistics</a></li></ol></li><li class="chapter-item expanded "><a href="usage/administration/monthly_active_users.html">Monthly Active Users</a></li><li class="chapter-item expanded "><a href="usage/administration/understanding_synapse_through_grafana_graphs.html">Understanding Synapse Through Grafana Graphs</a></li><li class="chapter-item expanded "><a href="usage/administration/useful_sql_for_admins.html">Useful SQL for Admins</a></li><li class="chapter-item expanded "><a href="usage/administration/database_maintenance_tools.html">Database Maintenance Tools</a></li><li class="chapter-item expanded "><a href="usage/administration/state_groups.html">State Groups</a></li><li class="chapter-item expanded "><a href="usage/administration/request_log.html">Request log format</a></li><li class="chapter-item expanded "><a href="usage/administration/admin_faq.html">Admin FAQ</a></li><li class="chapter-item expanded "><div>Scripts</div></li></ol></li><li class="chapter-item expanded "><li class="part-title">Development</li><li class="chapter-item expanded "><a href="development/contributing_guide.html">Contributing Guide</a></li><li class="chapter-item expanded "><a href="code_style.html">Code Style</a></li><li class="chapter-item expanded "><a href="development/reviews.html">Reviewing Code</a></li><li class="chapter-item expanded "><a href="development/releases.html">Release Cycle</a></li><li class="chapter-item expanded "><a href="development/git.html">Git Usage</a></li><li class="chapter-item expanded "><div>Testing</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="development/demo.html">Demo scripts</a></li></ol></li><li class="chapter-item expanded "><a href="opentracing.html">OpenTracing</a></li><li class="chapter-item expanded "><a href="development/database_schema.html">Database Schemas</a></li><li class="chapter-item expanded "><a href="development/experimental_features.html">Experimental features</a></li><li class="chapter-item expanded "><a href="development/dependencies.html">Dependency management</a></li><li class="chapter-item expanded "><div>Synapse Architecture</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="development/synapse_architecture/cancellation.html">Cancellation</a></li><li class="chapter-item expanded "><a href="log_contexts.html">Log Contexts</a></li><li class="chapter-item expanded "><a href="replication.html">Replication</a></li><li class="chapter-item expanded "><a href="tcp_replication.html">TCP Replication</a></li></ol></li><li class="chapter-item expanded "><a href="development/internal_documentation/index.html">Internal Documentation</a></li><li><ol class="section"><li class="chapter-item expanded "><div>Single Sign-On</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="development/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="development/cas.html">CAS</a></li></ol></li><li class="chapter-item expanded "><a href="development/room-dag-concepts.html">Room DAG concepts</a></li><li class="chapter-item expanded "><div>State Resolution</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="auth_chain_difference_algorithm.html">The Auth Chain Difference Algorithm</a></li></ol></li><li class="chapter-item expanded "><a href="media_repository.html" class="active">Media Repository</a></li><li class="chapter-item expanded "><a href="room_and_user_statistics.html">Room and User Statistics</a></li></ol></li><li class="chapter-item expanded "><div>Scripts</div></li><li class="chapter-item expanded affix "><li class="part-title">Other</li><li class="chapter-item expanded "><a href="deprecation_policy.html">Dependency Deprecation Policy</a></li><li class="chapter-item expanded "><a href="other/running_synapse_on_single_board_computers.html">Running Synapse on a Single-Board Computer</a></li></ol>
  74. </div>
  75. <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
  76. </nav>
  77. <div id="page-wrapper" class="page-wrapper">
  78. <div class="page">
  79. <div id="menu-bar-hover-placeholder"></div>
  80. <div id="menu-bar" class="menu-bar sticky bordered">
  81. <div class="left-buttons">
  82. <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
  83. <i class="fa fa-bars"></i>
  84. </button>
  85. <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
  86. <i class="fa fa-paint-brush"></i>
  87. </button>
  88. <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
  89. <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
  90. <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
  91. <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
  92. <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
  93. <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
  94. </ul>
  95. <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
  96. <i class="fa fa-search"></i>
  97. </button>
  98. </div>
  99. <h1 class="menu-title">Synapse</h1>
  100. <div class="right-buttons">
  101. <a href="print.html" title="Print this book" aria-label="Print this book">
  102. <i id="print-button" class="fa fa-print"></i>
  103. </a>
  104. <a href="https://github.com/matrix-org/synapse" title="Git repository" aria-label="Git repository">
  105. <i id="git-repository-button" class="fa fa-github"></i>
  106. </a>
  107. <a href="https://github.com/matrix-org/synapse/edit/develop/docs/media_repository.md" title="Suggest an edit" aria-label="Suggest an edit">
  108. <i id="git-edit-button" class="fa fa-edit"></i>
  109. </a>
  110. </div>
  111. </div>
  112. <div id="search-wrapper" class="hidden">
  113. <form id="searchbar-outer" class="searchbar-outer">
  114. <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
  115. </form>
  116. <div id="searchresults-outer" class="searchresults-outer hidden">
  117. <div id="searchresults-header" class="searchresults-header"></div>
  118. <ul id="searchresults">
  119. </ul>
  120. </div>
  121. </div>
  122. <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
  123. <script type="text/javascript">
  124. document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
  125. document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
  126. Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
  127. link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
  128. });
  129. </script>
  130. <div id="content" class="content">
  131. <main>
  132. <!-- Page table of contents -->
  133. <div class="sidetoc">
  134. <nav class="pagetoc"></nav>
  135. </div>
  136. <h1 id="media-repository"><a class="header" href="#media-repository">Media Repository</a></h1>
  137. <p><em>Synapse implementation-specific details for the media repository</em></p>
  138. <p>The media repository</p>
  139. <ul>
  140. <li>stores avatars, attachments and their thumbnails for media uploaded by local
  141. users.</li>
  142. <li>caches avatars, attachments and their thumbnails for media uploaded by remote
  143. users.</li>
  144. <li>caches resources and thumbnails used for URL previews.</li>
  145. </ul>
  146. <p>All media in Matrix can be identified by a unique
  147. <a href="https://spec.matrix.org/latest/client-server-api/#matrix-content-mxc-uris">MXC URI</a>,
  148. consisting of a server name and media ID:</p>
  149. <pre><code>mxc://&lt;server-name&gt;/&lt;media-id&gt;
  150. </code></pre>
  151. <h2 id="local-media"><a class="header" href="#local-media">Local Media</a></h2>
  152. <p>Synapse generates 24 character media IDs for content uploaded by local users.
  153. These media IDs consist of upper and lowercase letters and are case-sensitive.
  154. Other homeserver implementations may generate media IDs differently.</p>
  155. <p>Local media is recorded in the <code>local_media_repository</code> table, which includes
  156. metadata such as MIME types, upload times and file sizes.
  157. Note that this table is shared by the URL cache, which has a different media ID
  158. scheme.</p>
  159. <h3 id="paths"><a class="header" href="#paths">Paths</a></h3>
  160. <p>A file with media ID <code>aabbcccccccccccccccccccc</code> and its <code>128x96</code> <code>image/jpeg</code>
  161. thumbnail, created by scaling, would be stored at:</p>
  162. <pre><code>local_content/aa/bb/cccccccccccccccccccc
  163. local_thumbnails/aa/bb/cccccccccccccccccccc/128-96-image-jpeg-scale
  164. </code></pre>
  165. <h2 id="remote-media"><a class="header" href="#remote-media">Remote Media</a></h2>
  166. <p>When media from a remote homeserver is requested from Synapse, it is assigned
  167. a local <code>filesystem_id</code>, with the same format as locally-generated media IDs,
  168. as described above.</p>
  169. <p>A record of remote media is stored in the <code>remote_media_cache</code> table, which
  170. can be used to map remote MXC URIs (server names and media IDs) to local
  171. <code>filesystem_id</code>s.</p>
  172. <h3 id="paths-1"><a class="header" href="#paths-1">Paths</a></h3>
  173. <p>A file from <code>matrix.org</code> with <code>filesystem_id</code> <code>aabbcccccccccccccccccccc</code> and its
  174. <code>128x96</code> <code>image/jpeg</code> thumbnail, created by scaling, would be stored at:</p>
  175. <pre><code>remote_content/matrix.org/aa/bb/cccccccccccccccccccc
  176. remote_thumbnail/matrix.org/aa/bb/cccccccccccccccccccc/128-96-image-jpeg-scale
  177. </code></pre>
  178. <p>Older thumbnails may omit the thumbnailing method:</p>
  179. <pre><code>remote_thumbnail/matrix.org/aa/bb/cccccccccccccccccccc/128-96-image-jpeg
  180. </code></pre>
  181. <p>Note that <code>remote_thumbnail/</code> does not have an <code>s</code>.</p>
  182. <h2 id="url-previews"><a class="header" href="#url-previews">URL Previews</a></h2>
  183. <p>When generating previews for URLs, Synapse may download and cache various
  184. resources, including images. These resources are assigned temporary media IDs
  185. of the form <code>yyyy-mm-dd_aaaaaaaaaaaaaaaa</code>, where <code>yyyy-mm-dd</code> is the current
  186. date and <code>aaaaaaaaaaaaaaaa</code> is a random sequence of 16 case-sensitive letters.</p>
  187. <p>The metadata for these cached resources is stored in the
  188. <code>local_media_repository</code> and <code>local_media_repository_url_cache</code> tables.</p>
  189. <p>Resources for URL previews are deleted after a few days.</p>
  190. <h3 id="paths-2"><a class="header" href="#paths-2">Paths</a></h3>
  191. <p>The file with media ID <code>yyyy-mm-dd_aaaaaaaaaaaaaaaa</code> and its <code>128x96</code>
  192. <code>image/jpeg</code> thumbnail, created by scaling, would be stored at:</p>
  193. <pre><code>url_cache/yyyy-mm-dd/aaaaaaaaaaaaaaaa
  194. url_cache_thumbnails/yyyy-mm-dd/aaaaaaaaaaaaaaaa/128-96-image-jpeg-scale
  195. </code></pre>
  196. </main>
  197. <nav class="nav-wrapper" aria-label="Page navigation">
  198. <!-- Mobile navigation buttons -->
  199. <a rel="prev" href="auth_chain_difference_algorithm.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
  200. <i class="fa fa-angle-left"></i>
  201. </a>
  202. <a rel="next" href="room_and_user_statistics.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
  203. <i class="fa fa-angle-right"></i>
  204. </a>
  205. <div style="clear: both"></div>
  206. </nav>
  207. </div>
  208. </div>
  209. <nav class="nav-wide-wrapper" aria-label="Page navigation">
  210. <a rel="prev" href="auth_chain_difference_algorithm.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
  211. <i class="fa fa-angle-left"></i>
  212. </a>
  213. <a rel="next" href="room_and_user_statistics.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
  214. <i class="fa fa-angle-right"></i>
  215. </a>
  216. </nav>
  217. </div>
  218. <script type="text/javascript">
  219. window.playground_copyable = true;
  220. </script>
  221. <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
  222. <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
  223. <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
  224. <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
  225. <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
  226. <script src="book.js" type="text/javascript" charset="utf-8"></script>
  227. <!-- Custom JS scripts -->
  228. <script type="text/javascript" src="docs/website_files/table-of-contents.js"></script>
  229. </body>
  230. </html>