Struct RdfParser

Source

pub struct RdfParser { /* private fields */ }

Expand description

Parsers for RDF serialization formats.

It currently supports the following formats:

Note the useful options:

with_base_iri to resolve the relative IRIs.
rename_blank_nodes to rename the blank nodes to auto-generated numbers to avoid conflicts when merging RDF graphs together.
without_named_graphs to parse a single graph.
unchecked to skip some validations if the file is already known to be valid.

use oxrdfio::{RdfFormat, RdfParser};

let file = "<http://example.com/s> <http://example.com/p> <http://example.com/o> .";

let quads = RdfParser::from_format(RdfFormat::NTriples)
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;

assert_eq!(quads.len(), 1);
assert_eq!(quads[0].subject.to_string(), "<http://example.com/s>");

Implementations§

Source §

impl RdfParser

Source

pub fn from_format(format: RdfFormat) -> RdfParser

Builds a parser for the given format.

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pub fn format(&self) -> RdfFormat

The format the parser uses.

use oxrdfio::{RdfFormat, RdfParser};

assert_eq!(
    RdfParser::from_format(RdfFormat::Turtle).format(),
    RdfFormat::Turtle
);

Source

pub fn with_base_iri( self, base_iri: impl Into<String>, ) -> Result<RdfParser, IriParseError>

Provides an IRI that could be used to resolve the file relative IRIs.

use oxrdfio::{RdfFormat, RdfParser};

let file = "</s> </p> </o> .";

let quads = RdfParser::from_format(RdfFormat::Turtle)
    .with_base_iri("http://example.com")?
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;

assert_eq!(quads.len(), 1);
assert_eq!(quads[0].subject.to_string(), "<http://example.com/s>");

Source

pub fn with_default_graph( self, default_graph: impl Into<GraphName>, ) -> RdfParser

Provides the name graph name that should replace the default graph in the returned quads.

use oxrdf::NamedNode;
use oxrdfio::{RdfFormat, RdfParser};

let file = "<http://example.com/s> <http://example.com/p> <http://example.com/o> .";

let quads = RdfParser::from_format(RdfFormat::Turtle)
    .with_default_graph(NamedNode::new("http://example.com/g")?)
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;

assert_eq!(quads.len(), 1);
assert_eq!(quads[0].graph_name.to_string(), "<http://example.com/g>");

Source

pub fn without_named_graphs(self) -> RdfParser

Sets that the parser must fail if parsing a named graph.

This function restricts the parser to only parse a single RDF graph and not an RDF dataset.

use oxrdfio::{RdfFormat, RdfParser};

let file = "<http://example.com/s> <http://example.com/p> <http://example.com/o> <http://example.com/g> .";

let parser = RdfParser::from_format(RdfFormat::NQuads).without_named_graphs();
assert!(parser.for_reader(file.as_bytes()).next().unwrap().is_err());

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pub fn rename_blank_nodes(self) -> RdfParser

Renames the blank nodes ids from the ones set in the serialization to random ids.

This allows to avoid id conflicts when merging graphs together.

use oxrdfio::{RdfFormat, RdfParser};

let file = "_:a <http://example.com/p> <http://example.com/o> .";

let result1 = RdfParser::from_format(RdfFormat::NQuads)
    .rename_blank_nodes()
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;
let result2 = RdfParser::from_format(RdfFormat::NQuads)
    .rename_blank_nodes()
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;
assert_ne!(result1, result2);

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pub fn unchecked(self) -> RdfParser

Assumes the file is valid to make parsing faster.

It will skip some validations.

Note that if the file is actually not valid, broken RDF might be emitted by the parser.

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pub fn for_reader<R>(self, reader: R) -> ReaderQuadParser<R> ⓘ
where R: Read,

Parses from a Read implementation and returns an iterator of quads.

Reads are buffered.

use oxrdfio::{RdfFormat, RdfParser};

let file = "<http://example.com/s> <http://example.com/p> <http://example.com/o> .";

let quads = RdfParser::from_format(RdfFormat::NTriples)
    .for_reader(file.as_bytes())
    .collect::<Result<Vec<_>, _>>()?;

assert_eq!(quads.len(), 1);
assert_eq!(quads[0].subject.to_string(), "<http://example.com/s>");

Source

pub fn for_slice(self, slice: &[u8]) -> SliceQuadParser<'_> ⓘ

Parses from a byte slice and returns an iterator of quads.

use oxrdfio::{RdfFormat, RdfParser};

let file = b"<http://example.com/s> <http://example.com/p> <http://example.com/o> .";

let quads = RdfParser::from_format(RdfFormat::NTriples)
    .for_slice(file)
    .collect::<Result<Vec<_>, _>>()?;

assert_eq!(quads.len(), 1);
assert_eq!(quads[0].subject.to_string(), "<http://example.com/s>");