How to properly download excel file with Angular2

Question

This is the code of my service which makes post request with response an xls file :

exportInternalOrder(body) {
        let user_token: string = this.sessionService.getToken();
        let headers = new Headers();
        headers.append('responseType', 'arraybuffer');
        headers.append('Authorization', 'Bearer ' + user_token);
        return this.http.post(this.config.exportInternalOrder, body,{
            headers: headers
        }).map(res => new Blob([res._body],{ type: 'application/vnd.ms-excel' }));
    }

Which is supposed to handle response of excel file. This is the code invoking it:

let objToSend = this.makeObjToSend(false);
this.reportingService.exportExcel(objToSend)
    .subscribe(
        data => {
            this.exportData(data);
        },
        error => {
            this.errorFilterMsg.push({ severity: 'error', detail: 'Report exporting has failed!' });
        }
);

And this is the saving of the file (for some reason window.open does nothing):

exportData(data){       
        let blob = data;
        let a = document.createElement("a");
        a.href = URL.createObjectURL(blob);
        a.download = 'fileName.xls';
        document.body.appendChild(a);
        a.click();        
    }

But the file still saves as corrupted one. While using postman and curl it comes ok. Any help would be appreciated.

Answer 1

responseType shouldn't be set in headers, it's part of RequestOptionsArgs object which is passed as second argument in post function and RequestOptionsArgs contains headers, responseType and others, you can read more about it here. So, your code should look like this:

import { ResponseContentType } from '@angular/http';

exportInternalOrder(body) {
    let user_token: string = this.sessionService.getToken();
    let headers = new Headers();
    headers.append('Authorization', 'Bearer ' + user_token);
    return this.http.post(this.config.exportInternalOrder, body,{
        headers: headers,
        responseType: ResponseContentType.Blob
    }).map(res => new Blob([res._body],{ type: 'application/vnd.ms-excel' }));
}

Answer 2

I am writing this..it will be helpful for others who are looking for Angular 2 solution for file download functionality. Below piece of code works for me.

import { ResponseContentType } from '@angular/http';

exportInternalOrder(body) {
    let user_token: string = this.sessionService.getToken();
    let headers = new Headers();
    headers.append('Authorization', 'Bearer ' + user_token);
    return this.http.post(this.config.exportInternalOrder, body,{
        headers: headers,
        responseType: ResponseContentType.Blob}).map(res => new Blob([res.blob()],{ type: 'application/vnd.ms-excel' }));
}