fix frontend crash when node missing

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Removed
 
 ### Fixed
+ - Fixed frontend crash when instance node missing
 
 ### Security
 

backend/config/dev.exs

@@ -57,8 +57,8 @@ config :backend, Backend.Repo,
   pool_size: 10
 
 config :backend, :crawler,
-  status_age_limit_days: 28,
-  status_count_limit: 1000,
+  status_age_limit_days: 14,
+  status_count_limit: 500,
   personal_instance_threshold: 5,
   crawl_interval_mins: 60,
   crawl_workers: 10,

frontend/src/components/molecules/Cytoscape.tsx

@@ -40,7 +40,7 @@ class Cytoscape extends React.PureComponent<ICytoscapeProps> {
     this.cy = cytoscape({
       autoungrabify: true,
       container: container as any,
-      elements: this.props.elements,
+      elements: this.cleanElements(this.props.elements),
       hideEdgesOnViewport: true,
       hideLabelsOnViewport: true,
       layout: {
@@ -341,6 +341,16 @@ class Cytoscape extends React.PureComponent<ICytoscapeProps> {
     }
     this.cy.edges().addClass("hidden");
   };
+
+  /* Helper function to remove edges if source or target node is missing */
+  private cleanElements = (elements: cytoscape.ElementsDefinition): cytoscape.ElementsDefinition => {
+    const domains = new Set(elements.nodes.map(n => n.data.id));
+    const edges = elements.edges.filter(e => domains.has(e.data.source) && domains.has(e.data.target));
+    return {
+      edges,
+      nodes: elements.nodes
+    };
+  };
 }
 
 export default Cytoscape;