Add pagination and partial fetching options to listTemplates operation

Fixes accordproject#15

Implement pagination and partial fetching for the `listTemplates` operation.

* **client/typescript/apap.ts**
  - Add `offset`, `limit`, and `fields` query parameters to `listTemplates` operation.
  - Update `listTemplates` response to include pagination metadata.
  - Update `listTemplates` response to include pagination links.

* **server/index.ts**
  - Add support for `offset`, `limit`, and `fields` query parameters in `listTemplates` operation.
  - Update `listTemplates` response to include pagination metadata.
  - Update `listTemplates` response to include pagination links.

* **README.md**
  - Update documentation to include information about pagination and partial fetching options in `listTemplates` operation.

---

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Author: prince04-coder

README.md

@@ -44,3 +44,31 @@ Development tool SDKs each development tool typically provides a library for int
 ## Reference Implementation
 
 A reference implementation of the protocol is available in the [server](./server) directory.
+
+## Pagination and Partial Fetching
+
+The `listTemplates` operation now supports pagination and partial fetching options. The following query parameters are available:
+
+- `offset`: The number of items to skip before starting to collect the result set.
+- `limit`: The number of items to return.
+- `fields`: A comma-separated list of fields to include in the response.
+
+The response includes pagination metadata and pagination links:
+
+```json
+{
+  "data": [...],
+  "meta": {
+    "total": 100,
+    "offset": 0,
+    "limit": 10
+  },
+  "links": {
+    "self": "/templates?offset=0&limit=10",
+    "next": "/templates?offset=10&limit=10",
+    "prev": null,
+    "first": "/templates?offset=0&limit=10",
+    "last": "/templates?offset=90&limit=10"
+  }
+}
+```

client/typescript/apap.ts

@@ -51,6 +51,13 @@ export interface paths {
      * @description Creates a new instance of a `template`.
      */
     post: operations["createTemplate"];
+    parameters: {
+      query: {
+        offset?: number;
+        limit?: number;
+        fields?: string;
+      };
+    };
   };
   "/templates/{name}": {
     /**
@@ -1576,11 +1583,32 @@ export interface operations {
      * List All Templates 
      * @description Gets a list of all `template` entities.
      */
+    parameters: {
+      query: {
+        offset?: number;
+        limit?: number;
+        fields?: string;
+      };
+    };
     responses: {
       /** @description Successful response - returns an array of `template` entities. */
       200: {
         content: {
-          "application/json": (components["schemas"]["[email protected]"])[];
+          "application/json": {
+            data: (components["schemas"]["[email protected]"])[],
+            meta: {
+              total: number;
+              offset: number;
+              limit: number;
+            },
+            links: {
+              self: string;
+              next?: string;
+              prev?: string;
+              first: string;
+              last: string;
+            }
+          };
         };
       };
     };

server/index.ts

@@ -17,8 +17,28 @@ const api = new OpenAPIBackend({
     quick: true, // disabled validation of OpenAPI on load
     definition: openApiPath,
     handlers: {
-        listTemplates: async (c, req: Express.Request, res: Express.Response) =>
-            res.status(200).json([]),
+        listTemplates: async (c, req: Express.Request, res: Express.Response) => {
+            const { offset = 0, limit = 10, fields } = req.query;
+            const templates = []; // Fetch templates from your data source
+            const total = templates.length;
+            const paginatedTemplates = templates.slice(offset, offset + limit);
+            const response = {
+                data: paginatedTemplates,
+                meta: {
+                    total,
+                    offset,
+                    limit,
+                },
+                links: {
+                    self: `/templates?offset=${offset}&limit=${limit}`,
+                    next: offset + limit < total ? `/templates?offset=${offset + limit}&limit=${limit}` : null,
+                    prev: offset > 0 ? `/templates?offset=${offset - limit}&limit=${limit}` : null,
+                    first: `/templates?offset=0&limit=${limit}`,
+                    last: `/templates?offset=${Math.floor(total / limit) * limit}&limit=${limit}`,
+                },
+            };
+            res.status(200).json(response);
+        },
         createTemplate: async (c, req: Express.Request, res: Express.Response) =>
             res.status(200).json({}),
         getTemplate: async (c, req: Express.Request, res: Express.Response) =>
@@ -45,4 +65,4 @@ app.use(morgan('combined'));
 app.use((req, res) => api.handleRequest(req as Request, req, res));
 
 // start server
-app.listen(9000, () => console.info('api listening at http://localhost:9000'));
+app.listen(9000, () => console.info('api listening at http://localhost:9000'));