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oxigraph/lib/src/sparql/results.rs

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//! Utilities to read and write RDF results formats using [sparesults](https://crates.io/crates/sparesults).
//!
//! It supports [SPARQL Query Results XML Format (Second Edition)](https://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
//!
//! Usage example converting a JSON result file into a TSV result file:
//!
//! ```
//! use oxigraph::sparql::results::{QueryResultsFormat, QueryResultsParser, FromReadQueryResultsReader, QueryResultsSerializer};
//! use std::io::Result;
//!
//! fn convert_json_to_tsv(json_file: &[u8]) -> Result<Vec<u8>> {
//! let json_parser = QueryResultsParser::from_format(QueryResultsFormat::Json);
//! let tsv_serializer = QueryResultsSerializer::from_format(QueryResultsFormat::Tsv);
//! // We start to read the JSON file and see which kind of results it is
//! match json_parser.parse_read(json_file)? {
//! FromReadQueryResultsReader::Boolean(value) => {
//! // it's a boolean result, we copy it in TSV to the output buffer
//! tsv_serializer.serialize_boolean_to_write(Vec::new(), value)
//! }
//! FromReadQueryResultsReader::Solutions(solutions_reader) => {
//! // it's a set of solutions, we create a writer and we write to it while reading in streaming from the JSON file
//! let mut serialize_solutions_to_write = tsv_serializer.serialize_solutions_to_write(Vec::new(), solutions_reader.variables().to_vec())?;
//! for solution in solutions_reader {
//! serialize_solutions_to_write.write(&solution?)?;
//! }
//! serialize_solutions_to_write.finish()
//! }
//! }
//! }
//!
//! // Let's test with a boolean
//! assert_eq!(
//! convert_json_to_tsv(b"{\"boolean\":true}".as_slice()).unwrap(),
//! b"true"
//! );
//!
//! // And with a set of solutions
//! assert_eq!(
//! convert_json_to_tsv(b"{\"head\":{\"vars\":[\"foo\",\"bar\"]},\"results\":{\"bindings\":[{\"foo\":{\"type\":\"literal\",\"value\":\"test\"}}]}}".as_slice()).unwrap(),
//! b"?foo\t?bar\n\"test\"\t\n"
//! );
//! ```
pub use sparesults::{
FromReadQueryResultsReader, FromReadSolutionsReader, ParseError, QueryResultsFormat,
QueryResultsParser, QueryResultsSerializer, SyntaxError, TextPosition,
};