tests/testthat/test-rdf-roundtrip.R

In cboettig/emld: Ecological Metadata as Linked Data

testthat::context("test rdf roundtrips")

library(rdflib)
library(jsonlite)
library(jsonld)
library(magrittr)
library(testthat)

f <- system.file(file.path("tests",
                           eml_version(),
                           "eml.xml"), package="emld")

test_that("We can roundtrip into rdf and validate", {

  eml.json <- tempfile("eml", fileext = ".json")
  eml.xml <- tempfile("eml", fileext = ".xml")

  f %>%
  as_emld() %>%
  as_json() %>%
  rdf_parse("jsonld") %>%
  rdf_serialize(eml.json, "jsonld")

## frame & compact explicitly, even though as_emld should now do this on json input
frame <- system.file(paste0("frame/",
                            eml_version(),
                            "/eml-frame.json"), package = "emld")
context <- system.file(paste0("context/",
                       eml_version(),
                       "/eml-context.json"), package = "emld")
jsonld_frame(eml.json, frame) %>%
  jsonld_compact(context) %>%
  as_emld() %>%
  as_xml(eml.xml)
  expect_true(eml_validate(eml.xml))
})

test_that("We can roundtrip out to rdf-xml", {
  eml.rdf <- tempfile("eml", fileext = ".rdf")
  eml.json <- tempfile("eml", fileext = ".json")
  eml.xml <- tempfile("eml", fileext = ".xml")

## Into RDF-XML
f %>%
  as_emld() %>%
  as_json() %>%
  rdf_parse("jsonld") %>%
  rdf_serialize(eml.rdf, "rdfxml")

## Back into jsonld (via rdflib)
rdf_parse(eml.rdf, "rdfxml") %>%
  rdf_serialize(eml.json, "jsonld")


## Prove that as_emld frames and compacts automatically:
as_emld(eml.json) %>%
  as_xml(eml.xml)
expect_true(eml_validate(eml.xml))

})