Refactor Apollo Client setup to improve modularity and maintainability

- Introduced a new `createLink` function to encapsulate the link creation logic for Apollo Client.
- Updated `createApolloClient` to utilize the new `createLink` function, enhancing code organization.
- Simplified the handling of authorization headers by moving it to the link configuration.

packages/graphql/apollo/client.ts

@@ -1,18 +1,17 @@
 import { env as environment } from '../config/env';
 import { getToken } from '../config/token';
+import { createLink } from './link';
 import { ApolloClient, InMemoryCache } from '@apollo/client/core';
 
-type Parameters_ = { token: null | string | undefined };
+type Parameters = { token: null | string | undefined };
 
-export function createApolloClient(parameters?: Parameters_) {
+export function createApolloClient(parameters?: Parameters) {
   return new ApolloClient({
     cache: new InMemoryCache(),
-    headers: parameters?.token
-      ? {
-          Authorization: `Bearer ${parameters.token}`,
-        }
-      : undefined,
-    uri: environment.URL_GRAPHQL,
+    link: createLink({
+      token: parameters?.token,
+      uri: environment.URL_GRAPHQL,
+    }),
   });
 }
 

packages/graphql/apollo/link.ts

@@ -0,0 +1,16 @@
+import { ApolloLink, from, HttpLink } from '@apollo/client';
+
+type Parameters = { token: null | string | undefined; uri: string };
+
+export function createLink({ token, uri }: Parameters) {
+  const cacheLink = new ApolloLink((operation, forward) => {
+    return forward(operation);
+  });
+
+  const httpLink = new HttpLink({
+    headers: token ? { Authorization: `Bearer ${token}` } : undefined,
+    uri,
+  });
+
+  return from([cacheLink, httpLink]);
+}