{"result":{"depiction_url":null,"edges":{"references":{"objects":[{"created":"2020-05-30T05:48:05Z","object_id":{"id":1274,"is_a":["text","documentation","developerguide"],"name":"doc_developerguide_notifications","title":"Notifications","uri":"https:\/\/zotonic.com\/id\/1274"},"seq":1000000}],"predicate":{"id":332,"is_a":["meta","predicate"],"name":"references","title":{"_type":"trans","tr":{"en":"References"}},"uri":"https:\/\/zotonic.com\/id\/references"}},"subject":{"objects":[{"created":"2026-09-09T13:47:33Z","object_id":{"id":2555,"is_a":["categorization","keyword","keyword_information_type"],"name":"zotonic_topic_reference","title":"Reference","uri":"https:\/\/zotonic.com\/id\/2555"},"seq":1},{"created":"2026-09-09T13:47:33Z","object_id":{"id":2564,"is_a":["categorization","keyword","keyword_audience"],"name":"zotonic_topic_backend_developer","title":"Backend developer","uri":"https:\/\/zotonic.com\/id\/2564"},"seq":2},{"created":"2026-09-09T13:47:33Z","object_id":{"id":2574,"is_a":["categorization","keyword","keyword_domain"],"name":"zotonic_topic_content_relationships","title":"Content relationships","uri":"https:\/\/zotonic.com\/id\/2574"},"seq":3},{"created":"2026-09-09T13:47:33Z","object_id":{"id":2617,"is_a":["categorization","keyword","keyword_architecture"],"name":"zotonic_topic_edge","title":"Edge","uri":"https:\/\/zotonic.com\/id\/2617"},"seq":4},{"created":"2026-09-09T13:47:33Z","object_id":{"id":2627,"is_a":["categorization","keyword","keyword_architecture"],"name":"zotonic_topic_notification","title":"Notification","uri":"https:\/\/zotonic.com\/id\/2627"},"seq":5},{"created":"2026-09-09T13:47:33Z","object_id":{"id":2638,"is_a":["categorization","keyword","keyword_task"],"name":"zotonic_topic_edit","title":"Edit","uri":"https:\/\/zotonic.com\/id\/2638"},"seq":6}],"predicate":{"id":308,"is_a":["meta","predicate"],"name":"subject","title":{"_type":"trans","tr":{"en":"Keyword"}},"uri":"http:\/\/purl.org\/dc\/elements\/1.1\/subject"}}},"id":2126,"is_a":["text","documentation","reference","notification"],"links":[{"rel":"self","target":"https:\/\/zotonic.com\/.zotonic\/websub\/topic\/2126"},{"rel":"hub","target":"https:\/\/zotonic.com\/.zotonic\/websub"}],"medium":null,"medium_url":null,"name":"doc_notification_edge_delete","page_url":{"en":"https:\/\/zotonic.com\/docs\/2126\/observe_edge_delete-2","x-default":"https:\/\/zotonic.com\/docs\/2126\/observe_edge_delete-2"},"preview_url":null,"resource":{"version":3990,"pivot_location_lat":null,"title":"observe_edge_delete\/2","is_authoritative":true,"body":"<p>An edge has been deleted Note that the Context for this notification does not have the user who deleted the edge.<\/p>\n<p>Type:<\/p>\n<p><a href=\"\/id\/doc_developerguide_notifications#notification-notify\">notify<\/a><\/p>\n<p>Return:<\/p>\n<p>return value is ignored<\/p>\n<p><code>#edge_delete{}<\/code> properties:<\/p>\n<ul><li>subject_id: <code>m_rsc:resource()<\/code><\/li><li>predicate: <code>atom<\/code><\/li><li>object_id: <code>m_rsc:resource()<\/code><\/li><li>edge_id: <code>pos_integer<\/code><\/li><\/ul>\n<h2>Example<\/h2>\n<p>Perform some action when an edge is deleted:<\/p>\n<pre class=\"notranslate\"><code class=\"notranslate language-erlang\">-include_lib(&quot;zotonic_core\/include\/zotonic.hrl&quot;).\n-export([observe_edge_delete\/2]).\n\nobserve_edge_delete(#edge_delete{edge_id = Id}, Context) -&gt;\n    %% Consult the edge_log table to get the late edge&#39;s details\n    Edge = z_db:assoc_row(&quot;select * from edge_log where edge_id = $1&quot;, [Id], Context)),\n\n    ?DEBUG(Edge),\n    %% logged is when the deletion was logged; 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