> For the complete documentation index, see [llms.txt](https://docs.gapvelocity.ai/webmap/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.gapvelocity.ai/webmap/general/frontend/documentation/angular-client/webmap-interceptor-service.md).

# WebMap Interceptor Service

The `WebMAPInterceptor` service is used to intercept http request to handle special logic required for WebMAP WebAPI Requests.

## How it works

You can create an interceptor for any request of Angular. Any interceptor that you want to create needs to implement the `HttpInterceptor` interface. Using interceptor is all about changing outgoing request and incoming responses. If you want to make a change in the request, we need to clone the original and modify the new request.

```typescript
@Injectable()
export class WebMapInterceptor implements HttpInterceptor {
     ...
}
```

WebMap WebAPI may require a change to the request of Angular. The application can handle a `Pending Response` or `WebApiHeader`.

The `PendingResponseHeader` is used to mark that has a pending response that must be retrieved from the server. When the request is created, the core client add a new key/value in the header of the request, called `WM-Pending`= where the `id` is the request `id` in the server side used to recover the changes that should be send in the response.