blackmagic

Automagically Convert ‘XML’ to ‘JSON’/‘JSON’ to ‘XML’

Description

Given a character string of ‘XML’, an ‘xml2’ or ‘XML’ package document,
or a ‘URL’ to retrieve XML content from, convert said ‘XML’ to ‘JSON’
using the ‘xml-js’ ‘npm’ library https://www.npmjs.com/package/xml-js
by Yousuf Almarzooqi. Also handles the reverse (e.g. ‘JSON’ to ‘XML’).

NOTE

Please reconsider your apparent desire to use this package.

Automagic conversion of XML to JSON (or vice-versa) is rarely a good
idea and a path fraught with peril. There are so many options to tweak
to ensure you get what you think you want but likely truly want
something else entirely, such as a more minimal extract of the original
XML file.

Seriously consider parsing the XML/JSON then using purrr idioms to
extract the data you need into a proper list and then call
jsonlite::toJSON() or xml2::as_xml_document() on said list.

What’s Inside The Tin

The following functions are implemented:

• xml_to_json: Convert XML to JSON
• json_to_xml: Convert JSON to XML

Installation

devtools::install_github("hrbrmstr/blackmagic")

Usage

library(blackmagic)
# current verison
packageVersion("blackmagic")

## [1] '0.1.0'

Sample (defaults)

xml <- '<?xml version="1.0" encoding="utf-8"?>
<note importance="high" logged="true">
    <title>Happy</title>
    <todo>Work</todo>
    <todo>Play</todo>
</note>'
cat(xml_to_json(xml))

## {"declaration":{"attributes":{"version":"1.0","encoding":"utf-8"}},"elements":[{"type":"element","name":"note","attributes":{"importance":"high","logged":"true"},"elements":[{"type":"element","name":"title","elements":[{"type":"text","text":"Happy"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Work"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Play"}]}]}]}

Sample (xml2)

cat(xml_to_json(xml2::read_xml(xml)))

## {"declaration":{"attributes":{"version":"1.0","encoding":"UTF-8"}},"elements":[{"type":"element","name":"note","attributes":{"importance":"high","logged":"true"},"elements":[{"type":"element","name":"title","elements":[{"type":"text","text":"Happy"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Work"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Play"}]}]}]}

Sample (XML)

cat(xml_to_json(XML::xmlParse(xml)))

## {"declaration":{"attributes":{"version":"1.0","encoding":"utf-8"}},"elements":[{"type":"element","name":"note","attributes":{"importance":"high","logged":"true"},"elements":[{"type":"element","name":"title","elements":[{"type":"text","text":"Happy"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Work"}]},{"type":"element","name":"todo","elements":[{"type":"text","text":"Play"}]}]}]}

Sample (URL + saner tweaks)

cat(xml_to_json("https://httpbin.org/xml", spaces = 2, compact = FALSE, ignoreDeclaration = TRUE))

## {
##   "elements": [
##     {
##       "type": "comment",
##       "comment": "  A SAMPLE set of slides  "
##     },
##     {
##       "type": "element",
##       "name": "slideshow",
##       "attributes": {
##         "title": "Sample Slide Show",
##         "date": "Date of publication",
##         "author": "Yours Truly"
##       },
##       "elements": [
##         {
##           "type": "comment",
##           "comment": " TITLE SLIDE "
##         },
##         {
##           "type": "element",
##           "name": "slide",
##           "attributes": {
##             "type": "all"
##           },
##           "elements": [
##             {
##               "type": "element",
##               "name": "title",
##               "elements": [
##                 {
##                   "type": "text",
##                   "text": "Wake up to WonderWidgets!"
##                 }
##               ]
##             }
##           ]
##         },
##         {
##           "type": "comment",
##           "comment": " OVERVIEW "
##         },
##         {
##           "type": "element",
##           "name": "slide",
##           "attributes": {
##             "type": "all"
##           },
##           "elements": [
##             {
##               "type": "element",
##               "name": "title",
##               "elements": [
##                 {
##                   "type": "text",
##                   "text": "Overview"
##                 }
##               ]
##             },
##             {
##               "type": "element",
##               "name": "item",
##               "elements": [
##                 {
##                   "type": "text",
##                   "text": "Why "
##                 },
##                 {
##                   "type": "element",
##                   "name": "em",
##                   "elements": [
##                     {
##                       "type": "text",
##                       "text": "WonderWidgets"
##                     }
##                   ]
##                 },
##                 {
##                   "type": "text",
##                   "text": " are great"
##                 }
##               ]
##             },
##             {
##               "type": "element",
##               "name": "item"
##             },
##             {
##               "type": "element",
##               "name": "item",
##               "elements": [
##                 {
##                   "type": "text",
##                   "text": "Who "
##                 },
##                 {
##                   "type": "element",
##                   "name": "em",
##                   "elements": [
##                     {
##                       "type": "text",
##                       "text": "buys"
##                     }
##                   ]
##                 },
##                 {
##                   "type": "text",
##                   "text": " WonderWidgets"
##                 }
##               ]
##             }
##           ]
##         }
##       ]
##     }
##   ]
## }

Sample (some saner tweaks)

'<?xml version="1.0" encoding="UTF-8"?>
<bookstore>
  <book category="cooking">
    <title lang="en">Everyday Italian</title>
    <author>Giada De Laurentiis</author>
    <year>2005</year>
    <price>30.00</price>
  </book>
  <book category="children">
    <title lang="en">Harry Potter</title>
    <author>J K. Rowling</author>
    <year>2005</year>
    <price>29.99</price>
  </book>
  <book category="web">
    <title lang="en">Learning XML</title>
    <author>Erik T. Ray</author>
    <year>2003</year>
    <price>39.95</price>
  </book>
</bookstore>' -> books
cat(xml_to_json(books, spaces = 2, compact = TRUE, ignoreDeclaration = TRUE))

## {
##   "bookstore": {
##     "book": [
##       {
##         "_attributes": {
##           "category": "cooking"
##         },
##         "title": {
##           "_attributes": {
##             "lang": "en"
##           },
##           "_text": "Everyday Italian"
##         },
##         "author": {
##           "_text": "Giada De Laurentiis"
##         },
##         "year": {
##           "_text": "2005"
##         },
##         "price": {
##           "_text": "30.00"
##         }
##       },
##       {
##         "_attributes": {
##           "category": "children"
##         },
##         "title": {
##           "_attributes": {
##             "lang": "en"
##           },
##           "_text": "Harry Potter"
##         },
##         "author": {
##           "_text": "J K. Rowling"
##         },
##         "year": {
##           "_text": "2005"
##         },
##         "price": {
##           "_text": "29.99"
##         }
##       },
##       {
##         "_attributes": {
##           "category": "web"
##         },
##         "title": {
##           "_attributes": {
##             "lang": "en"
##           },
##           "_text": "Learning XML"
##         },
##         "author": {
##           "_text": "Erik T. Ray"
##         },
##         "year": {
##           "_text": "2003"
##         },
##         "price": {
##           "_text": "39.95"
##         }
##       }
##     ]
##   }
## }

The other way ’round

cat(json_to_xml(jsonlite::toJSON(head(mtcars, 2)), spaces=2))

## <0>
##   <mpg>21</mpg>
##   <cyl>6</cyl>
##   <disp>160</disp>
##   <hp>110</hp>
##   <drat>3.9</drat>
##   <wt>2.62</wt>
##   <qsec>16.46</qsec>
##   <vs>0</vs>
##   <am>1</am>
##   <gear>4</gear>
##   <carb>4</carb>
##   <_row>Mazda RX4</_row>
## </0>
## <1>
##   <mpg>21</mpg>
##   <cyl>6</cyl>
##   <disp>160</disp>
##   <hp>110</hp>
##   <drat>3.9</drat>
##   <wt>2.875</wt>
##   <qsec>17.02</qsec>
##   <vs>0</vs>
##   <am>1</am>
##   <gear>4</gear>
##   <carb>4</carb>
##   <_row>Mazda RX4 Wag</_row>
## </1>

Code of Conduct

Please note that this project is released with a Contributor Code of
Conduct. By participating in this project you agree to
abide by its terms.