Maps an Odata Collection to a kendo GridDataResult. Useful when providing Angular-Grid async odata data

gridMap.ts

import { map } from "../../../../node_modules/rxjs/operators";
import { GridDataResult } from "../../../../node_modules/@progress/kendo-angular-grid";
import { OperatorFunction } from "../../../../node_modules/rxjs";
export interface IOdataCollection<T> {
    "@odata.context"?: string;
    "@odata.count"?: number | undefined;
    "value"?: T[];
}

/**Maps an array or IOdataCollection to a kendo GridDataResult
 * @param count {number} overides the count from the array length or odata.count returned from request
 * @returns OperatorFunction
 */
export const gridMap = <T>(count:number = undefined): OperatorFunction<IOdataCollection<T> | T[], GridDataResult> =>
   input$ => input$.pipe(map(m => Array.isArray(m)? <GridDataResult>{ data: m, total:count|| m.length }: <GridDataResult>{ data: m.value, total:count || m["@odata.count"] }))
 /*Example  
class example {
   data$: Observable<GridDataResult>;
   data2$: Observable<GridDataResult>;
   constructor(private http: HttpClient) {
      this.data$ = this.http.get<IOdataCollection<any>>("https://services.odata.org/TripPinRESTierService/People?$count=true")
         .pipe(gridMap());
         this.data2$ = this.http.get<any>("https://services.odata.org/TripPinRESTierService/People")
         .pipe(map(m=>m.value), gridMap(m.value.length))

   }
}

<kendo-grid [data]="data$ |async"></kendo-grid>
<kendo-grid [data]="data2$ |async"></kendo-grid>

Demo
=======
https://stackblitz.com/edit/angular-kendo-grid-gridmap
*/