[vtkusers] VTK-js: how to read a .json file

Wed Jul 26 10:44:02 EDT 2017

Dear all,

thank you very very much for your help! Everything is working now!

Cristina

On Wed, Jul 26, 2017 at 4:12 PM, Sebastien Jourdain <
sebastien.jourdain at kitware.com> wrote:

> Hi Christina,
>
> I think the issue is inside your JSON file which might not be properly
> formed.
> To make sure your file is properly formatted, you can use a service like
> below to spot the issue quickly.
>
> https://jsonlint.com/
>
> Regarding the "require" or "import" method to ingest your file, they
> should both work but we prefer to use the "import" syntax.
>
> Seb
>
>
>
> On Wed, Jul 26, 2017 at 7:35 AM, Aron Helser <aron.helser at kitware.com>
> wrote:
>
>> Hi Cristina,
>> I think the 'require' function may be the problem - in vtk-js and
>> ParaViewWeb, we typically use 'import', like this:
>>
>> import localPresetImages from '../../presets.json';
>>
>> Try it that way?
>> Regards,
>> Aron
>>
>> On Wed, Jul 26, 2017 at 5:31 AM, Cristina Oyarzun <
>> coyarzunlaura at googlemail.com> wrote:
>>
>>> Dear Scott and Aron,
>>>
>>> thank you for your answers. I was indeed using an older version of
>>> Webpack, but I already upgraded to the newest version. Unfortunately I keep
>>> getting errors when I try to read the JSON file. To this I have to add that
>>> although I have been using vtk for quite a long time now, I am completely
>>> new to javascript.
>>>
>>> If I understood correctly with webpack 2 I do not need to add anything
>>> to the webpack.config.js to be able to read json files in the index.js. Is
>>> this right? However, I try to read the json file with the following command
>>> in index.js:
>>>
>>> const json = require('./file.json');
>>>
>>> apart of that line of code I didnt write anything else related to the json file. I got the following error:
>>>
>>> ERROR in ./src/file.json
>>> Module build failed: SyntaxError: Unexpected token / in JSON at position 146
>>>     at Object.parse (native)
>>>     at Object.module.exports (D:\VTK-JS\node_modules\json-loader\index.js:4:
>>> 49)
>>>  @ ./src/index.js 285:13-35
>>>  @ ./src/index.js
>>>  @ multi (webpack)-dev-server/client?http://localhost:8080 ./src/index.js
>>> webpack: Failed to compile.
>>>
>>> Thank you very much!!!
>>>
>>> Cristina
>>>
>>>
>>>
>>> On Fri, Jul 21, 2017 at 5:50 PM, Scott Wittenburg <
>>> scott.wittenburg at kitware.com> wrote:
>>>
>>>> Hi Cristina,
>>>>
>>>> In vtk.js we now use webpack2 (in master at least, you may have picked
>>>> an older version though), and the webpack2 documentation states that you no
>>>> longer need a loader for json:
>>>>
>>>> https://webpack.js.org/guides/migrating/#json-loader-is-not-
>>>> required-anymore
>>>>
>>>> Is your project also using webpack2?  In that case you shouldn't need
>>>> the json loader.  Also, when you refer to "Build-in modules of Node.js",
>>>> does that refer specifically to this:
>>>>
>>>> https://github.com/sindresorhus/builtin-modules
>>>>
>>>> or do you mean something else?
>>>>
>>>> Cheers,
>>>> Scott
>>>>
>>>> On Fri, Jul 21, 2017 at 8:57 AM, Aron Helser <aron.helser at kitware.com>
>>>> wrote:
>>>>
>>>>> Hi Cristina,
>>>>> ParaViewWeb uses this webpack 1.x loader:
>>>>> {
>>>>>     test: /\.json$/,
>>>>>     loader: 'json-loader',
>>>>>   },
>>>>> That should allow you to 'include' a json file in your javascript, and
>>>>> then you might need to use the built-in JSON.parse() to turn it into an
>>>>> object.
>>>>>
>>>>> Regards,
>>>>> Aron
>>>>>
>>>>> On Fri, Jul 21, 2017 at 4:43 AM, Cristina Oyarzun via vtkusers <
>>>>> vtkusers at vtk.org> wrote:
>>>>>
>>>>>> Dear all,
>>>>>>
>>>>>> I visualized several actors using VTK-js. Now I want to read a .json
>>>>>> file and according to the information that it is included there assign
>>>>>> different colors to the actors.
>>>>>>
>>>>>> Unfortunately as soon as I try to use the Build-in modules of Node.js
>>>>>> I start getting errors. I didnt manage to find out how do I have to adapt
>>>>>> the "webpack.config.js" (or the "package.json"?) so that it works.
>>>>>>
>>>>>> I found somewhere in a forum that it should work by adding " target:
>>>>>> 'node' " to the webpack.config.js but it didnt. Any help would be great!
>>>>>>
>>>>>> Thank you!
>>>>>> Cristina
>>>>>>
>>>>>> _______________________________________________
>>>>>> Powered by www.kitware.com
>>>>>>
>>>>>> Visit other Kitware open-source projects at
>>>>>> http://www.kitware.com/opensource/opensource.html
>>>>>>
>>>>>> Please keep messages on-topic and check the VTK FAQ at:
>>>>>> http://www.vtk.org/Wiki/VTK_FAQ
>>>>>>
>>>>>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>>>>>
>>>>>> Follow this link to subscribe/unsubscribe:
>>>>>> http://public.kitware.com/mailman/listinfo/vtkusers
>>>>>>
>>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Powered by www.kitware.com
>>>>>
>>>>> Visit other Kitware open-source projects at
>>>>> http://www.kitware.com/opensource/opensource.html
>>>>>
>>>>> Please keep messages on-topic and check the VTK FAQ at:
>>>>> http://www.vtk.org/Wiki/VTK_FAQ
>>>>>
>>>>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>>>>
>>>>> Follow this link to subscribe/unsubscribe:
>>>>> http://public.kitware.com/mailman/listinfo/vtkusers
>>>>>
>>>>>
>>>>
>>>
>>
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/vtkusers
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20170726/b69b178f/attachment.html>