43 lines
1.4 KiB
Elixir
43 lines
1.4 KiB
Elixir
defmodule RDF.NTriples.Reader do
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@moduledoc """
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`RDF::NTriples` provides support for reading the N-Triples serialization
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format.
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N-Triples is a line-based plain-text format for encoding an RDF graph.
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It is a very restricted, explicit and well-defined subset of both
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[Turtle](http://www.w3.org/TeamSubmission/turtle/) and
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[Notation3](http://www.w3.org/TeamSubmission/n3/) (N3).
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The MIME content type for N-Triples files is `text/plain` and the
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recommended file extension is `.nt`.
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An example of an RDF statement in N-Triples format:
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<https://hex.pm/> <http://purl.org/dc/terms/title> "Hex" .
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"""
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use RDF.Reader
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def read_string(content, _opts \\ []) do
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with {:ok, tokens, _} <- tokenize(content),
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{:ok, ast} <- parse(tokens) do
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{:ok, build_graph(ast)}
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else
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{:error, {error_line, :ntriples_lexer, error_descriptor}, _error_line_again} ->
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{:error, "N-Triple scanner error on line #{error_line}: #{inspect error_descriptor}"}
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{:error, {error_line, :ntriples_parser, error_descriptor}} ->
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{:error, "N-Triple parser error on line #{error_line}: #{inspect error_descriptor}"}
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end
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end
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defp tokenize(content), do: content |> to_charlist |> :ntriples_lexer.string
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defp parse(tokens), do: tokens |> :ntriples_parser.parse
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defp build_graph(ast) do
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Enum.reduce ast, RDF.Graph.new, fn(triple, graph) ->
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RDF.Graph.add(graph, triple)
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end
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end
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end
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