fix: fix deduplication of links when name attribute is not used

In some twingraph instances, arcs and edges are identified by an 'id'
column, and not a 'name'. This fix makes the use of the id column the
new default behavior, because ids are supposed to be uniques (whereas
entity and link names can be reused).
If no id is defined for links, the webapp will try to fall back to
the previous behavior by looking for the 'name' attribute.

src/views/Instance/data.js

@@ -177,7 +177,7 @@ async function _fetchTwingraphDatasetContent(organizationId, datasetId, dataSour
         'properties, src.id as src, dst.id as dst'
     );
   }
-  return { nodes, edges };
+  return { nodes, edges, edgeCategories };
 }
 
 async function _fetchDataFromTwingraphDatasets(organizationId, datasets) {
@@ -186,9 +186,13 @@ async function _fetchDataFromTwingraphDatasets(organizationId, datasets) {
     if (content[label] === undefined) content[label] = [];
     if (content[label].find((item) => item.id === node.id) === undefined) content[label].push(node);
   };
-  const addEdge = (src, rel, dst, type) => {
+  const addEdge = (src, rel, dst, type, identityAttribute) => {
     if (content[type] === undefined) content[type] = [];
-    if (!content[type].some((item) => item.name === rel.name && item.source === src && item.target === dst))
+    if (
+      !content[type].some(
+        (item) => item[identityAttribute] === rel[identityAttribute] && item.source === src && item.target === dst
+      )
+    )
       content[type].push({
         source: src,
         target: dst,
@@ -197,16 +201,28 @@ async function _fetchDataFromTwingraphDatasets(organizationId, datasets) {
   };
 
   for (const datasetId of datasets) {
-    const { nodes, edges } = await _fetchTwingraphDatasetContent(organizationId, datasetId);
+    const {
+      nodes,
+      edges,
+      edgeCategories: edgeAttributesByType,
+    } = await _fetchTwingraphDatasetContent(organizationId, datasetId);
 
     for (const label in nodes) {
       for (const node of nodes[label]) {
         addNode(node, label);
       }
     }
+
     for (const type in edges) {
+      const edgeAttributes = edgeAttributesByType.find((el) => el.type === type)?.keys ?? [];
+      let edgeIdentityAttribute = 'id';
+      if (!edgeAttributes.includes('id')) {
+        if (!edgeAttributes.includes('name')) {
+          console.warn(`Links of type ${type} don't have "id" nor "name" attributes. Some arcs may be lost.`);
+        } else edgeIdentityAttribute = 'name';
+      }
       for (const edge of edges[type]) {
-        addEdge(edge.src, edge.properties, edge.dst, type);
+        addEdge(edge.src, edge.properties, edge.dst, type, edgeIdentityAttribute);
       }
     }
   }