Bruker:Jeblad/Module:JSONstat/dok

The purpose of this module is to demonstrate handling of JSON-stat in Lua with closure-based instances modelled as lazy facades. The instances will not be created before boundraries are passed, that is a method returns a value that is wrapped in a closure. This makes a fairly efficient implementation for simple access.

The library can be used as simple calls through the invoke parser function, or as a support library. A main purpose for the lib is to provide Vega-formatted data, often constrained or adapted somehow to fit better with other available data.

Primary access point is the load-method, which will parse one of several sources and return an instance according to the provided data. In Lua-code the instance can be navigated by using provided methods, while in wikitext it is possible to use layout (format) parameters. One such predefined layout could be to create data for Vega, which is nothing more than the dataset values as an expanded table.

Usage

In wikicode the module will typically be called like one of the following

{{#invoke:JSONstat | load | updated }}
{{#invoke:JSONstat | load | Q123456 | label }}
{{#invoke:JSONstat | load | Bruker:Jeblad/SSB01222.json | ${source:%.10s} }}
{{#invoke:JSONstat | load | { ... } | expanded }}

The first call use the connected item to identify the external JSON-stat dataset (not implemented). The layout updated reports the datestamp when the dataset was last updated.

The second call identifies an item to use for further identification of a JSON-dataset (not implemented). The layout label reports the label for the dataset.

The third call identifies a page that contain the dataset. This use an inline format for layout, and reports a truncated source string.

The fourth call use an inline definition of the dataset. This use a layout that reports the values from the expanded form, that is a form that can be used in Vega.

Similar calls in Lua-code would be like the following

local jsonstat = require('Module:JSONstat')
jsonstat.load().updated()
jsonstat.load( 'updated' )
jsonstat.load( 'Q123456' ).label()
jsonstat.load( 'Q123456', 'label' )
jsonstat.load( 'Bruker:Jeblad/SSB01222.json' ).layout( '${source:%.10s}' )
jsonstat.load( 'Bruker:Jeblad/SSB01222.json', '${source:%.10s}' )
jsonstat.load( '{ ... }' ).expanded()
jsonstat.load( '{ ... }', 'expanded' )