Création/mise à jour basique d'un DAD

client/src/gql/client.tsx

@@ -3,6 +3,7 @@ import { Config } from '../config';
 import { WebSocketLink } from "@apollo/client/link/ws";
 import { RetryLink } from "@apollo/client/link/retry";
 import { SubscriptionClient } from "subscriptions-transport-ws";
+import { User } from '../types/user';
 
 const subscriptionClient = new SubscriptionClient(Config.subscriptionEndpoint, {
   reconnect: true,
@@ -14,7 +15,42 @@ const link = new RetryLink({attempts: {max: 2}}).split(
   new HttpLink({ uri: Config.graphQLEndpoint, credentials: 'include' })
 );
 
+const cache = new InMemoryCache({
+  typePolicies: {
+    Workgroup: {
+      fields: {
+        members: {
+          merge: mergeArrayByField<User>("id"),
+        }
+      }
+    }
+  }
+});
+
 export const client = new ApolloClient<any>({
-  cache: new InMemoryCache(),
+  cache: cache,
   link: link,
-});
+});
+
+function mergeArrayByField<T>(fieldName: string) {
+  return (existing: T[] = [], incoming: T[], { readField, mergeObjects }) => {
+    const merged: any[] = existing ? existing.slice(0) : [];
+    const objectFieldToIndex: Record<string, number> = Object.create(null);
+    if (existing) {
+      existing.forEach((obj, index) => {
+        objectFieldToIndex[readField(fieldName, obj)] = index;
+      });
+    }
+    incoming.forEach(obj => {
+      const field = readField(fieldName, obj);
+      const index = objectFieldToIndex[field];
+      if (typeof index === "number") {
+        merged[index] = mergeObjects(merged[index], obj);
+      } else {
+        objectFieldToIndex[name] = merged.length;
+        merged.push(obj);
+      }
+    });
+    return merged;
+  }
+}