# vega-parser

Parse Vega specifications to runtime dataflow descriptions.

## API Reference

<a name="parse" href="#parse">#</a>
vega.<b>parse</b>(<i>specification</i>[, <i>config</i>])
[<>](https://github.com/vega/vega-loader/blob/master/src/parse.js "Source")

Parses a Vega JSON *specification* as input and produces a reactive dataflow
graph description for a visualization. The output description uses the format
of the [vega-runtime](https://github.com/vega/vega-runtime) module. To create
a visualization, use the runtime dataflow description as the input to a Vega
[View](https://github.com/vega/vega-view) instance.

The optional *config* object provides visual encoding defaults for marks,
scales, axes and legends. Different configuration settings can be used to
change choices of layout, color, type faces, font sizes and more to realize
different chart themes. For more, see the configuration documentation below
or view the source code defining Vega's
[default configuration](https://github.com/vega/vega-parser/blob/master/src/config.js).

In addition to passing configuration options to this [parse](#parse) method,
Vega JSON specifications may also include a top-level `"config"` block
specifying configuration properties. Configuration options defined within a
Vega JSON file take precedence over those provided to the parse method.

## Configuration

The Vega parser accepts a configuration file that defines default settings
for a variety of visual encoding choices. Different configuration files can be
used to "theme" charts with a customized look and feel. A configuration file is
simply a JavaScript object with a set of named properties, grouped by type.

For more information regarding the supported configuration options, please
see the [Vega config documentation](https://vega.github.io/vega/docs/config/).
