How to read a file from local file system with vega-lite?

[jkfe]

The sample vega-lite code below is getting data from an url.

Instead, I would like it to read the .csv from my local file system.

How to do that?

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {"url": "mydata.csv"},  
  "mark": "line",
  "encoding": {
    "x": {"field": "date", "type": "temporal"},
    "y": {"field": "price", "type": "quantitative"}
  }
}

Thanks.

[Anonymous]

Hi @jkfe ,

Depending on the information you provide, you can make the local .csv file accessible via a URL by making it available locally or via a Web server. You can follow the steps below:

1. If you are using Python version 3.x, navigate to the directory containing the .csv file on the command line and run the following command:

python -m http.server

2. Ensure that the web pages are served from the same local server to avoid cross-domain issues. You can modify the Vega-Lite specification to use the URL of the data source: 

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {"url": "http://localhost:8000/mydata.csv"},  
  "mark": "line",
  "encoding": {
    "x": {"field": "date", "type": "temporal"},
    "y": {"field": "price", "type": "quantitative"}
  }
}

Best Regards,

Ada Wang

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[jkfe]

Thanks for answer.

That would require a local web server as I understand. Wouldn't like to have that. Want to access a file directly from the file system.

[amitchandak]

@jkfe , Try this in blank query in power query

let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ZY5BDoIwEEWvQhqXCis3rL0FZVHLCKOlrXRoJIa7W9oIGrqa/vz3ZqqKvbnO4uPs4GQHveCsDJ+OyLqyKDy0Im+RuvGaoylSJaYnhQSFP+d3ZzRnx03UCIqW1b2EXqgRXJJL5y+xk30b8w/ei+GRego1/JlBS9Ogbnf2V0rYDUE1CQ5XLHCYaLKQMoLemkEozraFCz7tcTug3PHPUWhCEoQ+JPN6fRpmVtcf", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t]),
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}}),
#"Parsed JSON" = Table.TransformColumns(#"Changed Type",{},Json.Document),
#"Expanded Column1" = Table.ExpandRecordColumn(#"Parsed JSON", "Column1", {"$schema", "data", "mark", "encoding"}, {"Column1.$schema", "Column1.data", "Column1.mark", "Column1.encoding"}),
#"Expanded Column1.data" = Table.ExpandRecordColumn(#"Expanded Column1", "Column1.data", {"values"}, {"Column1.data.values"}),
#"Added Custom" = Table.AddColumn(#"Expanded Column1.data", "Custom", each Table.Unpivot( Table.FromRecords({[Column1.encoding]}), {"x","y"}, "attribute", "value")),
#"Expanded Custom" = Table.ExpandTableColumn(#"Added Custom", "Custom", {"attribute", "value"}, {"Custom.attribute", "Custom.value"}),
#"Expanded Custom.value" = Table.ExpandRecordColumn(#"Expanded Custom", "Custom.value", {"field", "type"}, {"Custom.value.field", "Custom.value.type"})
in
#"Expanded Custom.value"

[jkfe]

Sorry. Didn't understand the code. Appreciate if you can explain. For instance, where to inform the file name/path.