# How to use HttpDataSetReader to load local .vti files？
**URL:** https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266
**Category:** Web
**Created:** [April 11, 2022, 6:18am UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266 "2022-04-11T06:18:09Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@zhangzhi93](https://discourse.vtk.org/u/zhangzhi93)
#### Post date: [April 11, 2022, 6:18am UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/1 "2022-04-11T06:18:09Z")
```auto
const reader = vtkHttpDataSetReader.newInstance({
fetchGzip: true,
});
reader.setUrl('/3d/headsq.vti', { loadData: true,}).then(() => {
console.log(reader.getOutputData())
});
```
This code will throw error:
* * *
but when i use https it doesn't give an error：
```auto
const reader = vtkHttpDataSetReader.newInstance({
fetchGzip: true,
});
reader.setUrl('https://kitware.github.io/vtk-js/data/volume/headsq.vti', { loadData: true }).then(() => {
console.log(reader.getOutputData())
});
```
* * *
When I set the loadData as false, can load the file,but when i use getPointData().getScalars().getRange(),will throw a error `Cannot read properties of null (reading 'getRange')`
```auto
reader.setUrl('/3d/headsq.vti', { loadData: false }).then(() => {
volumeData = reader.getOutputData()
});
// some code ....
const initialRange = volumeData.getPointData().getScalars().getRange();
```
I created a project with vite and vue3, and the files are placed in the public/3d/ directory
The headsq.vti file is what I downloaded from the vtk.js example，Local files and files on https are exactly the same。
---
### Author:  [@Sebastien\_Jourdain](https://discourse.vtk.org/u/Sebastien_Jourdain)
#### Post date: [April 11, 2022, 2:47pm UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/2 "2022-04-11T14:47:19Z")
What is the question?
Did you do the following in your code?
`import 'vtk.js/Sources/IO/Core/DataAccessHelper/JSZipDataAccessHelper';`
Also if you say “Don’t load the data”, it is expected that you do not have data…
---
### Author:  [@zhangzhi93](https://discourse.vtk.org/u/zhangzhi93)
#### Post date: [April 12, 2022, 12:53am UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/3 "2022-04-12T00:53:38Z")
yes, I have imported JSZipDataAccessHelper
My question is why the same file, when loaded locally, will report an error。
---
### Author:  [@Sebastien\_Jourdain](https://discourse.vtk.org/u/Sebastien_Jourdain)
#### Post date: [April 12, 2022, 2:37pm UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/4 "2022-04-12T14:37:08Z")
Are you sure you got the full directory? HttpDataSetReader load directories, not a single file.
---
### Author:  [@zhangzhi93](https://discourse.vtk.org/u/zhangzhi93)
#### Post date: [April 13, 2022, 1:33am UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/5 "2022-04-13T01:33:27Z")
yes, i am sure.
This is the file directory:
The file has loaded, but the data structure is different from loading from https.
This is loaded from local file directory:
An error will be reported when executing `pako.inflate(new Uint8Array(array.buffer)`
This is loaded from https:
---
### Author:  [@Sebastien\_Jourdain](https://discourse.vtk.org/u/Sebastien_Jourdain)
#### Post date: [April 13, 2022, 2:38pm UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/6 "2022-04-13T14:38:44Z")
What is the extension of that file in data (`.gz`)? You should check what you are getting, but I’m pretty sure, you are not getting the content of that file, hence the issue…
---
### Author:  [@YHJ](https://discourse.vtk.org/u/YHJ)
#### Post date: [October 28, 2022, 4:11am UTC](https://discourse.vtk.org/t/how-to-use-httpdatasetreader-to-load-local-vti-files/8266/7 "2022-10-28T04:11:00Z")
I used the npm “serve” package for the local test and set up the npm proxy separately.