如何生成pdf，并将其作为http响应发送，以便在能够以pdf格式下载的客户端上发送？

Question

我正在使用 pdfkit ，从模板生成pdf。我想将其作为http响应发送，以便在客户端我们能够以pdf格式下载。 但在客户端，它已被破坏。请告诉我原因。我认为有任何编码问题，我认为我们必须在服务器端代码中发送encode('utf-8') ....

服务器端代码（django ）

address_template_path = os.path.join(settings.BASE_DIR,'address_template.html')

# generate pdf
add_str = render_to_string(address_template_path)
pdfkit.from_string(add_str, file_location)

address_pdf = open(file_location)
response = HttpResponse(address_pdf.read(), 
content_type='application/pdf')  # Generates the response as pdf response.

客户端（JavaScript + angularjs）

$scope.downloadAddress = function(reqData){

        service.getAddress(reqData).then(function(response){
            if(response.data.error){
                toastr.error(response.data.message ,"Unsuccessful");
            }else{
                var file = new Blob([ str2ab(response.data) ], {
                    type : 'application/pdf'
                });
                //trick to download store a file having its URL
                var fileURL = URL.createObjectURL(file);
                var a         = document.createElement('a');
                a.href        = fileURL;
                a.target      = '_blank';
                a.download    = envelopeObj.customer_name+'_'+ 'envId_'+envelopeObj.envelope_id+'.pdf';
                document.body.appendChild(a);
                a.click();
            }
        });
    };

function str2ab(str) {
          var buf = new ArrayBuffer(str.length*2); // 2 bytes for each char
          var bufView = new Uint16Array(buf);
          for (var i=0, strLen=str.length; i < strLen; i++) {
            bufView[i] = str.charCodeAt(i);
          }
          return buf;
        }

我从Converting between strings and ArrayBuffers

获得上述功能str2ab