Add advanced queries and policies guides to GraphQL docs

docusaurus/docs/cms/api/graphql.md

@@ -76,7 +76,6 @@ The GraphQL API does not support media upload. Use the [REST API `POST /upload`
 The GraphQL API exposes documents using only the `documentId` field. The previous numeric `id` is no longer available here, although it is still returned by the REST API for backward compatibility (see [breaking change](/cms/migration/v4-to-v5/breaking-changes/use-document-id) for details).
 :::
 
-
 ## Queries
 
 Queries in GraphQL are used to fetch data without modifying it.
@@ -1111,3 +1110,12 @@ mutation DeleteRestaurant($documentId: ID!, $locale: I18NLocaleCode) {
   }
 }
 ```
+
+## Advanced use cases
+
+Click on the following cards for short guides on more advanced use cases leveraging the GraphQL API and Strapi features: 
+
+<CustomDocCardsWrapper>
+  <CustomDocCard emoji="🖼️" title="Advanced queries" description="View examples of multi-level queries and custom resolver chains for the GraphQL API." link="/cms/api/graphql/advanced-queries" />
+  <CustomDocCard emoji="🖼️" title="Advanced policies" description="View examples of advanced policies such as conditional visibility and group membership for the GraphQL API." link="/cms/api/graphql/advanced-policies" />
+</CustomDocCardsWrapper>

docusaurus/docs/cms/api/graphql/advanced-policies.md

@@ -0,0 +1,64 @@
+---
+title: Advanced policies for GraphQL
+displayed_sidebar: cmsSidebar
+tags:
+  - GraphQL API
+  - policies
+---
+
+# Advanced policies for the GraphQL API
+
+Requests sent to the [GraphQL API](/cms/api/graphql) pass through Strapi's [middlewares](/cms/backend-customization/middlewares.md) and [policies](/cms/backend-customization/policies.md) system. Policies can be attached to resolvers to implement complex authorization rules, as shown in the present short guide.
+
+For additional information on GraphQL policies, please refer to the [GraphQL plugin configuration](/cms/plugins/graphql#extending-the-schema) documentation.
+
+## Conditional visibility
+
+To limit the number of returned entries for unauthenticated users you can write a policy that modifies resolver arguments:
+
+```ts title="/src/policies/limit-public-results.ts"
+export default async (policyContext, config, { strapi }) => {
+  const { state, args } = policyContext;
+
+  if (!state.user) {
+    args.limit = 4; // only return 4 results for public
+  }
+
+  return true;
+};
+```
+
+Register the policy in `/config/policies.ts` and apply it to a resolver:
+
+```ts title="/config/policies.ts"
+export default {
+  'api::restaurant.restaurant': {
+    find: [ 'global::limit-public-results' ],
+  },
+};
+```
+
+## Group membership
+
+Policies can access `policyContext.state.user` to check group membership, as in the following example:
+
+```ts title="/src/policies/is-group-member.ts"
+export default async ({ state }, config, { strapi }) => {
+  const userGroups = await strapi.query('plugin::users-permissions.group').findMany({
+    where: { users: { id: state.user.id } },
+  });
+  return userGroups.some(g => g.name === config.group);
+};
+```
+
+Use the policy with the following configuration:
+
+```ts title="/config/policies.ts"
+export default {
+  'api::restaurant.restaurant': {
+    find: [{ name: 'global::is-group-member', config: { group: 'editors' } }],
+  },
+};
+```
+
+With this setup the resolver only returns results if the authenticated user belongs to the `editors` group.

docusaurus/docs/cms/api/graphql/advanced-queries.md

@@ -0,0 +1,52 @@
+---
+title: Advanced queries for GraphQL
+displayed_sidebar: cmsSidebar
+tags:
+  - GraphQL API
+---
+
+# Advanced queries for the GraphQL API
+
+Strapi's [GraphQL API](/cms/api/graphql) resolves many queries automatically, but complex data access can require deeper relation fetching or chaining resolvers. The present short guide explains how to handle such advanced scenarios.
+
+For additional information, please refer to the [GraphQL customization](/cms/plugins/graphql#extending-the-schema) documentation.
+
+## Multi-level queries
+
+Use nested selection sets to fetch relations several levels deep, as in the following example:
+
+```graphql
+{
+  restaurants {
+    documentId
+    name
+    categories {
+      documentId
+      name
+      parent {
+        documentId
+        name
+      }
+    }
+  }
+}
+```
+
+The GraphQL plugin automatically resolves nested relations. If you need to apply custom logic at a specific level, create a custom resolver for that field.
+
+## Resolver chains
+
+Custom resolvers can call other resolvers to reuse existing logic. A common pattern is to resolve permissions or context data in a parent resolver and pass it down to child resolvers, as in the following example:
+
+```js title="/src/api/restaurant/resolvers/restaurant.ts"
+export default {
+  Query: {
+    restaurants: async (parent, args, ctx) => {
+      const documents = await strapi.documents('api::restaurant.restaurant').findMany(args);
+      return documents.map(doc => ctx.request.graphql.resolve('Restaurant', doc));
+    },
+  },
+};
+```
+
+In this example the parent resolver fetches restaurants using the [Document Service API](/cms/api/document-service), then delegates to the generated `Restaurant` resolver provided by the plugin so default behavior such as field selection still applies.

docusaurus/docs/cms/plugins/graphql.md

@@ -673,6 +673,10 @@ When [extending the GraphQL schema](#extending-the-schema), the `resolversConfig
 * [policies with the `policies`](#policies) key
 * and [middlewares with the `middlewares`](#middlewares) key
 
+:::tip
+The [advanced queries](/cms/api/graphql/advanced-queries) guide might contain additional information suitable for your use case, including multi-level queries and custom resolvers examples.
+:::
+
 ###### Authorization configuration
 
 By default, the authorization of a GraphQL request is handled by the registered authorization strategy that can be either [API token](/cms/features/api-tokens) or through the [Users & Permissions plugin](#usage-with-the-users--permissions-plugin). The Users & Permissions plugin offers a more granular control.
@@ -877,6 +881,10 @@ export default {
 
 </details>
 
+:::tip
+The [advanced policies](/cms/api/graphql/advanced-policies) guide might contain additional information suitable for your use case.
+:::
+
 ###### Middlewares
 
 [Middlewares](/cms/backend-customization/middlewares) can be applied to a GraphQL resolver through the `resolversConfig.[MyResolverName].middlewares` key. The only difference between the GraphQL and REST implementations is that the `config` key becomes `options`.