rdf-ex/lib/rdf/serialization/reader.ex

65 lines
2 KiB
Elixir

defmodule RDF.Serialization.Reader do
@moduledoc """
General functions for reading a `RDF.Graph` or `RDF.Dataset` from a serialization file or encoded-string.
If no base IRI is provided with the `base` option on any of these functions,
the `RDF.IRI.default_base/0` is used.
You probably won't use these functions directly, but instead use the automatically
generated functions with same name on a `RDF.Serialization.Format`, which implicitly
use the proper `RDF.Serialization.Decoder` module.
"""
@doc """
Reads and decodes a serialized graph or dataset from a string.
It returns an `{:ok, data}` tuple, with `data` being the deserialized graph or
dataset, or `{:error, reason}` if an error occurs.
"""
def read_string(decoder, content, opts \\ []) do
decoder.decode(content, with_base(opts))
end
@doc """
Reads and decodes a serialized graph or dataset from a string.
As opposed to `read_string`, it raises an exception if an error occurs.
"""
def read_string!(decoder, content, opts \\ []) do
decoder.decode!(content, with_base(opts))
end
@doc """
Reads and decodes a serialized graph or dataset from a file.
It returns an `{:ok, data}` tuple, with `data` being the deserialized graph or
dataset, or `{:error, reason}` if an error occurs.
"""
def read_file(decoder, file, opts \\ []) do
case File.read(file) do
{:ok, content} -> read_string(decoder, content, with_base(opts))
{:error, reason} -> {:error, reason}
end
end
@doc """
Reads and decodes a serialized graph or dataset from a file.
As opposed to `read_file`, it raises an exception if an error occurs.
"""
def read_file!(decoder, file, opts \\ []) do
with content = File.read!(file) do
read_string!(decoder, content, with_base(opts))
end
end
defp with_base(opts) do
cond do
Keyword.has_key?(opts, :base) -> opts
base = RDF.IRI.default_base() -> Keyword.put(opts, :base, base)
true -> opts
end
end
end