In BenjaminLouis/xmlprocessor: Process xml file: create, fill template, export

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)

library(xmlprocessor)

Fill a xml template

One of the main goal of package {xmlprocessor} is to facilitate the serial creatoin of xml file. From a xml template, you can use a dataframe to replace text and attribute values.

Starting with the creation and printing of a template :

library(xml2)
template <- read_xml("<parent>
                        <child nom='child1'>
                          <grandchild>grandchild1</grandchild>
                          <grandchild>grandchild2</grandchild>
                        </child>
                        <child nom='child2'>
                          null
                        </child>
                      </parent>")
print(template)                   

The xml template contains 4 values that can be changed : grandchild1, grandchild2, child1 and child2. The first two are texts and the two latter are attributes values.

To fill the template with different values, you can build a dataframe where the columns names are the exact text to be replaced. For text values, this should be the whole text between xml element (<...>thistext) and for attributes values, this should be the whole text between quotes.

toreplace <- data.frame(child1 = c("Ben", "Thomas"), child2 = c("Sarah", "Marie"),
grandchild1 = c("Brad", "Angelica"), grandchild2 = c("Jude", "Lea"))
toreplace

You can then fill the template with information contained in toreplace to create a list with two xml documents with the structure as template but where grandchild1, grandchild2, child1 and child2 are replaced by the corresponding values in toreplace.

# No export, no collapsing
newxml <- xml_fill_template(xmltemplate = template, with = toreplace)
print(newxml[[1]])
print(newxml[[2]])

It is also possible to collapse the filled xml documents ont a big one by specifying a root node name with the collapse argument. Note that if the given root node name is als the root node name of template, the latter must contain only one child (which can contains several children and so on).

# Export and collapsing
newxml <- xml_fill_template(xmltemplate = template, with = toreplace, collapse = "grandparent")
print(newxml)

Eventually, you can export the xml document by specifying a path to a folder with the export argument and a name (or names) of the xml file(s) exported with the name argument.

BenjaminLouis/xmlprocessor documentation built on May 27, 2019, 3:28 p.m.