Adopt new I/O API for serialization

js/src/store.rs

@@ -4,7 +4,7 @@ use crate::format_err;
 use crate::model::*;
 use crate::utils::to_err;
 use js_sys::{Array, Map};
-use oxigraph::io::{DatasetFormat, GraphFormat};
+use oxigraph::io::{DatasetFormat, GraphFormat, RdfFormat};
 use oxigraph::model::*;
 use oxigraph::sparql::QueryResults;
 use oxigraph::store::Store;
@@ -191,34 +191,22 @@ impl JsStore {
     }
 
     pub fn dump(&self, mime_type: &str, from_graph_name: &JsValue) -> Result<String, JsValue> {
+        let Some(format) = RdfFormat::from_media_type(mime_type) else {
+            return Err(format_err!("Not supported MIME type: {mime_type}"));
+        };
         let from_graph_name =
             if let Some(graph_name) = FROM_JS.with(|c| c.to_optional_term(from_graph_name))? {
-                Some(graph_name.try_into()?)
+                Some(GraphName::try_from(graph_name)?)
             } else {
                 None
             };
-
         let mut buffer = Vec::new();
-        if let Some(graph_format) = GraphFormat::from_media_type(mime_type) {
+        if let Some(from_graph_name) = &from_graph_name {
-            self.store
+            self.store.dump_graph(&mut buffer, format, from_graph_name)
-                .dump_graph(
-                    &mut buffer,
-                    graph_format,
-                    &from_graph_name.unwrap_or(GraphName::DefaultGraph),
-                )
-                .map_err(to_err)?;
-        } else if let Some(dataset_format) = DatasetFormat::from_media_type(mime_type) {
-            if from_graph_name.is_some() {
-                return Err(format_err!(
-                    "The target graph name parameter is not available for dataset formats"
-                ));
-            }
-            self.store
-                .dump_dataset(&mut buffer, dataset_format)
-                .map_err(to_err)?;
         } else {
-            return Err(format_err!("Not supported MIME type: {mime_type}"));
+            self.store.dump_dataset(&mut buffer, format)
         }
+        .map_err(to_err)?;
         String::from_utf8(buffer).map_err(to_err)
     }
 }

lib/src/io/mod.rs

@@ -7,6 +7,7 @@ pub mod write;
 
 pub use self::format::{DatasetFormat, GraphFormat};
 pub use self::read::{DatasetParser, GraphParser};
+#[allow(deprecated)]
 pub use self::write::{DatasetSerializer, GraphSerializer};
 pub use oxrdfio::{
     FromReadQuadReader, ParseError, RdfFormat, RdfParser, RdfSerializer, SyntaxError,

lib/src/io/write.rs

@@ -1,3 +1,5 @@
+#![allow(deprecated)]
+
 //! Utilities to write RDF graphs and datasets.
 
 use crate::io::{DatasetFormat, GraphFormat};
@@ -28,6 +30,7 @@ use std::io::{self, Write};
 /// assert_eq!(buffer.as_slice(), "<http://example.com/s> <http://example.com/p> <http://example.com/o> .\n".as_bytes());
 /// # Result::<_,Box<dyn std::error::Error>>::Ok(())
 /// ```
+#[deprecated(note = "Use RdfSerializer instead")]
 pub struct GraphSerializer {
     inner: RdfSerializer,
 }
@@ -110,6 +113,7 @@ impl<W: Write> TripleWriter<W> {
 /// assert_eq!(buffer.as_slice(), "<http://example.com/s> <http://example.com/p> <http://example.com/o> <http://example.com/g> .\n".as_bytes());
 /// # Result::<_,Box<dyn std::error::Error>>::Ok(())
 /// ```
+#[deprecated(note = "Use RdfSerializer instead")]
 pub struct DatasetSerializer {
     inner: RdfSerializer,
 }

lib/src/sparql/error.rs

@@ -1,4 +1,4 @@
-use crate::io::read::ParseError;
+use crate::io::{ParseError, SyntaxError};
 use crate::storage::StorageError;
 use std::convert::Infallible;
 use std::error;
@@ -14,10 +14,10 @@ pub enum EvaluationError {
     /// An error from the storage.
     Storage(StorageError),
     /// An error while parsing an external RDF file.
-    GraphParsing(ParseError),
+    GraphParsing(SyntaxError),
     /// An error while parsing an external result file (likely from a federated query).
     ResultsParsing(sparesults::ParseError),
-    /// An error returned during store IOs or during results write.
+    /// An error returned during store or results I/Os.
     Io(io::Error),
     /// An error returned during the query evaluation itself (not supported custom function...).
     Query(QueryError),
@@ -132,7 +132,10 @@ impl From<io::Error> for EvaluationError {
 impl From<ParseError> for EvaluationError {
     #[inline]
     fn from(error: ParseError) -> Self {
-        Self::GraphParsing(error)
+        match error {
+            ParseError::Syntax(error) => Self::GraphParsing(error),
+            ParseError::Io(error) => Self::Io(error),
+        }
     }
 }
 

lib/src/sparql/model.rs

@@ -1,5 +1,4 @@
-use crate::io::GraphFormat;
+use crate::io::{RdfFormat, RdfSerializer};
-use crate::io::GraphSerializer;
 use crate::model::*;
 use crate::sparql::error::EvaluationError;
 use oxrdf::{Variable, VariableRef};
@@ -96,7 +95,7 @@ impl QueryResults {
     ///
     /// ```
     /// use oxigraph::store::Store;
-    /// use oxigraph::io::GraphFormat;
+    /// use oxigraph::io::{RdfFormat, GraphFormat};
     /// use oxigraph::model::*;
     ///
     /// let graph = "<http://example.com> <http://example.com> <http://example.com> .\n";
@@ -105,19 +104,19 @@ impl QueryResults {
     /// store.load_graph(graph.as_bytes(), GraphFormat::NTriples, GraphNameRef::DefaultGraph, None)?;
     ///
     /// let mut results = Vec::new();
-    /// store.query("CONSTRUCT WHERE { ?s ?p ?o }")?.write_graph(&mut results, GraphFormat::NTriples)?;
+    /// store.query("CONSTRUCT WHERE { ?s ?p ?o }")?.write_graph(&mut results, RdfFormat::NTriples)?;
     /// assert_eq!(results, graph.as_bytes());
     /// # Result::<_,Box<dyn std::error::Error>>::Ok(())
     /// ```
     pub fn write_graph(
         self,
         write: impl Write,
-        format: GraphFormat,
+        format: impl Into<RdfFormat>,
     ) -> Result<(), EvaluationError> {
         if let Self::Graph(triples) = self {
-            let mut writer = GraphSerializer::from_format(format).triple_writer(write);
+            let mut writer = RdfSerializer::from_format(format.into()).serialize_to_write(write);
             for triple in triples {
-                writer.write(&triple?)?;
+                writer.write_triple(&triple?)?;
             }
             writer.finish()?;
             Ok(())

lib/src/sparql/update.rs

@@ -1,5 +1,4 @@
-use crate::io::read::ParseError;
+use crate::io::{RdfFormat, RdfParser};
-use crate::io::{GraphFormat, GraphParser};
 use crate::model::{GraphName as OxGraphName, GraphNameRef, Quad as OxQuad};
 use crate::sparql::algebra::QueryDataset;
 use crate::sparql::dataset::DatasetView;
@@ -166,7 +165,7 @@ impl<'a, 'b: 'a> SimpleUpdateEvaluator<'a, 'b> {
             from.as_str(),
             "application/n-triples, text/turtle, application/rdf+xml",
         )?;
-        let format = GraphFormat::from_media_type(&content_type).ok_or_else(|| {
+        let format = RdfFormat::from_media_type(&content_type).ok_or_else(|| {
             EvaluationError::msg(format!(
                 "Unsupported Content-Type returned by {from}: {content_type}"
             ))
@@ -175,15 +174,17 @@ impl<'a, 'b: 'a> SimpleUpdateEvaluator<'a, 'b> {
             GraphName::NamedNode(graph_name) => graph_name.into(),
             GraphName::DefaultGraph => GraphNameRef::DefaultGraph,
         };
-        let mut parser = GraphParser::from_format(format);
+        let mut parser = RdfParser::from_format(format)
+            .rename_blank_nodes()
+            .without_named_graphs()
+            .with_default_graph(to_graph_name);
         if let Some(base_iri) = &self.base_iri {
-            parser = parser
+            parser = parser.with_base_iri(base_iri.as_str()).map_err(|e| {
-                .with_base_iri(base_iri.as_str())
+                EvaluationError::msg(format!("The LOAD IRI '{base_iri}' is invalid: {e}"))
-                .map_err(|e| ParseError::invalid_base_iri(base_iri, e))?;
+            })?;
         }
-        for t in parser.read_triples(body) {
+        for q in parser.parse_read(body) {
-            self.transaction
+            self.transaction.insert(q?.as_ref())?;
-                .insert(t?.as_ref().in_graph(to_graph_name))?;
         }
         Ok(())
     }

lib/src/storage/error.rs

@@ -1,4 +1,4 @@
-use crate::io::read::ParseError;
+use crate::io::{read::ParseError, RdfFormat};
 use std::error::Error;
 use std::fmt;
 use std::io;
@@ -179,6 +179,8 @@ pub enum SerializerError {
     Io(io::Error),
     /// An error raised during the lookup in the store.
     Storage(StorageError),
+    /// A format compatible with [RDF dataset](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-dataset) is required.
+    DatasetFormatExpected(RdfFormat),
 }
 
 impl fmt::Display for SerializerError {
@@ -187,6 +189,10 @@ impl fmt::Display for SerializerError {
         match self {
             Self::Io(e) => e.fmt(f),
             Self::Storage(e) => e.fmt(f),
+            Self::DatasetFormatExpected(format) => write!(
+                f,
+                "A RDF format supporting datasets was expected, {format} found"
+            ),
         }
     }
 }
@@ -197,6 +203,7 @@ impl Error for SerializerError {
         match self {
             Self::Io(e) => Some(e),
             Self::Storage(e) => Some(e),
+            Self::DatasetFormatExpected(_) => None,
         }
     }
 }
@@ -221,6 +228,9 @@ impl From<SerializerError> for io::Error {
         match error {
             SerializerError::Storage(error) => error.into(),
             SerializerError::Io(error) => error,
+            SerializerError::DatasetFormatExpected(_) => {
+                io::Error::new(io::ErrorKind::InvalidInput, error.to_string())
+            }
         }
     }
 }

lib/src/store.rs

@@ -24,9 +24,7 @@
 //! # Result::<_, Box<dyn std::error::Error>>::Ok(())
 //! ```
 use crate::io::read::ParseError;
-use crate::io::{
+use crate::io::{DatasetFormat, DatasetParser, GraphFormat, GraphParser, RdfFormat, RdfSerializer};
-    DatasetFormat, DatasetParser, DatasetSerializer, GraphFormat, GraphParser, GraphSerializer,
-};
 use crate::model::*;
 use crate::sparql::{
     evaluate_query, evaluate_update, EvaluationError, Query, QueryExplanation, QueryOptions,
@@ -612,13 +610,13 @@ impl Store {
     /// ```
     pub fn dump_graph<'a>(
         &self,
-        writer: impl Write,
+        write: impl Write,
-        format: GraphFormat,
+        format: impl Into<RdfFormat>,
         from_graph_name: impl Into<GraphNameRef<'a>>,
     ) -> Result<(), SerializerError> {
-        let mut writer = GraphSerializer::from_format(format).triple_writer(writer);
+        let mut writer = RdfSerializer::from_format(format.into()).serialize_to_write(write);
         for quad in self.quads_for_pattern(None, None, None, Some(from_graph_name.into())) {
-            writer.write(quad?.as_ref())?;
+            writer.write_triple(quad?.as_ref())?;
         }
         writer.finish()?;
         Ok(())
@@ -642,12 +640,16 @@ impl Store {
     /// ```
     pub fn dump_dataset(
         &self,
-        writer: impl Write,
+        write: impl Write,
-        format: DatasetFormat,
+        format: impl Into<RdfFormat>,
     ) -> Result<(), SerializerError> {
-        let mut writer = DatasetSerializer::from_format(format).quad_writer(writer);
+        let format = format.into();
+        if !format.supports_datasets() {
+            return Err(SerializerError::DatasetFormatExpected(format));
+        }
+        let mut writer = RdfSerializer::from_format(format).serialize_to_write(write);
         for quad in self.iter() {
-            writer.write(&quad?)?;
+            writer.write_quad(&quad?)?;
         }
         writer.finish()?;
         Ok(())

lib/tests/store.rs

@@ -1,4 +1,4 @@
-use oxigraph::io::{DatasetFormat, GraphFormat};
+use oxigraph::io::{DatasetFormat, GraphFormat, RdfFormat};
 use oxigraph::model::vocab::{rdf, xsd};
 use oxigraph::model::*;
 use oxigraph::store::Store;
@@ -211,11 +211,7 @@ fn test_dump_graph() -> Result<(), Box<dyn Error>> {
     }
 
     let mut buffer = Vec::new();
-    store.dump_graph(
+    store.dump_graph(&mut buffer, RdfFormat::NTriples, GraphNameRef::DefaultGraph)?;
-        &mut buffer,
-        GraphFormat::NTriples,
-        GraphNameRef::DefaultGraph,
-    )?;
     assert_eq!(
         buffer.into_iter().filter(|c| *c == b'\n').count(),
         NUMBER_OF_TRIPLES
@@ -231,7 +227,7 @@ fn test_dump_dataset() -> Result<(), Box<dyn Error>> {
     }
 
     let mut buffer = Vec::new();
-    store.dump_dataset(&mut buffer, DatasetFormat::NQuads)?;
+    store.dump_dataset(&mut buffer, RdfFormat::NQuads)?;
     assert_eq!(
         buffer.into_iter().filter(|c| *c == b'\n').count(),
         NUMBER_OF_TRIPLES

python/src/io.rs

@@ -3,8 +3,9 @@
 use crate::model::{PyQuad, PyTriple};
 use oxigraph::io::read::{ParseError, QuadReader, TripleReader};
 use oxigraph::io::{
-    DatasetFormat, DatasetParser, DatasetSerializer, GraphFormat, GraphParser, GraphSerializer,
+    DatasetFormat, DatasetParser, GraphFormat, GraphParser, RdfFormat, RdfSerializer,
 };
+use oxigraph::model::QuadRef;
 use pyo3::exceptions::{PyIOError, PySyntaxError, PyValueError};
 use pyo3::prelude::*;
 use pyo3::types::PyBytes;
@@ -120,34 +121,34 @@ pub fn parse(
 /// b'<http://example.com> <http://example.com/p> "1" .\n'
 #[pyfunction]
 pub fn serialize(input: &PyAny, output: PyObject, mime_type: &str, py: Python<'_>) -> PyResult<()> {
+    let Some(format) = RdfFormat::from_media_type(mime_type) else {
+        return Err(PyValueError::new_err(format!(
+            "Not supported MIME type: {mime_type}"
+        )));
+    };
     let output = if let Ok(path) = output.extract::<PathBuf>(py) {
         PyWritable::from_file(&path, py).map_err(map_io_err)?
     } else {
         PyWritable::from_data(output)
     };
-    if let Some(graph_format) = GraphFormat::from_media_type(mime_type) {
+    let mut writer = RdfSerializer::from_format(format).serialize_to_write(output);
-        let mut writer = GraphSerializer::from_format(graph_format).triple_writer(output);
     for i in input.iter()? {
-            writer
+        let i = i?;
-                .write(&*i?.extract::<PyRef<PyTriple>>()?)
+        if let Ok(triple) = i.extract::<PyRef<PyTriple>>() {
-                .map_err(map_io_err)?;
+            writer.write_triple(&*triple)
+        } else {
+            let quad = i.extract::<PyRef<PyQuad>>()?;
+            let quad = QuadRef::from(&*quad);
+            if !quad.graph_name.is_default_graph() && !format.supports_datasets() {
+                return Err(PyValueError::new_err(
+                    "The {format} format does not support named graphs",
+                ));
             }
-        writer.finish().map_err(map_io_err)?;
+            writer.write_quad(quad)
-        Ok(())
-    } else if let Some(dataset_format) = DatasetFormat::from_media_type(mime_type) {
-        let mut writer = DatasetSerializer::from_format(dataset_format).quad_writer(output);
-        for i in input.iter()? {
-            writer
-                .write(&*i?.extract::<PyRef<PyQuad>>()?)
-                .map_err(map_io_err)?;
         }
-        writer.finish().map_err(map_io_err)?;
+        .map_err(map_io_err)?;
-        Ok(())
-    } else {
-        Err(PyValueError::new_err(format!(
-            "Not supported MIME type: {mime_type}"
-        )))
     }
+    writer.finish().map_err(map_io_err)
 }
 
 #[pyclass(name = "TripleReader", module = "pyoxigraph")]

python/src/sparql.rs

@@ -1,4 +1,4 @@
-use crate::io::{allow_threads_unsafe, map_io_err, map_parse_error};
+use crate::io::{allow_threads_unsafe, map_io_err};
 use crate::map_storage_error;
 use crate::model::*;
 use oxigraph::model::Term;
@@ -234,7 +234,7 @@ pub fn map_evaluation_error(error: EvaluationError) -> PyErr {
         EvaluationError::Parsing(error) => PySyntaxError::new_err(error.to_string()),
         EvaluationError::Storage(error) => map_storage_error(error),
         EvaluationError::Io(error) => map_io_err(error),
-        EvaluationError::GraphParsing(error) => map_parse_error(error),
+        EvaluationError::GraphParsing(error) => PySyntaxError::new_err(error.to_string()),
         EvaluationError::Query(error) => PyValueError::new_err(error.to_string()),
         _ => PyRuntimeError::new_err(error.to_string()),
     }

python/src/store.rs

@@ -3,7 +3,7 @@
 use crate::io::{allow_threads_unsafe, map_io_err, map_parse_error, PyReadable, PyWritable};
 use crate::model::*;
 use crate::sparql::*;
-use oxigraph::io::{DatasetFormat, GraphFormat};
+use oxigraph::io::{DatasetFormat, GraphFormat, RdfFormat};
 use oxigraph::model::{GraphName, GraphNameRef};
 use oxigraph::sparql::Update;
 use oxigraph::store::{self, LoaderError, SerializerError, StorageError, Store};
@@ -522,10 +522,10 @@ impl PyStore {
     /// :type output: io(bytes) or str or pathlib.Path
     /// :param mime_type: the MIME type of the RDF serialization.
     /// :type mime_type: str
-    /// :param from_graph: if a triple based format is requested, the store graph from which dump the triples. By default, the default graph is used.
+    /// :param from_graph: the store graph from which dump the triples. Required if the serialization format does not support named graphs. If it does supports named graphs the full dataset is written.
     /// :type from_graph: NamedNode or BlankNode or DefaultGraph or None, optional
     /// :rtype: None
-    /// :raises ValueError: if the MIME type is not supported or the `from_graph` parameter is given with a quad syntax.
+    /// :raises ValueError: if the MIME type is not supported or the `from_graph` parameter is not given with a syntax not supporting named graphs.
     /// :raises IOError: if an I/O error happens during a quad lookup
     ///
     /// >>> store = Store()
@@ -547,34 +547,23 @@ impl PyStore {
         } else {
             PyWritable::from_data(output)
         };
+        let Some(format) = RdfFormat::from_media_type(mime_type) else {
+            return Err(PyValueError::new_err(format!(
+                "Not supported MIME type: {mime_type}"
+            )));
+        };
         let from_graph_name = if let Some(graph_name) = from_graph {
             Some(GraphName::from(&PyGraphNameRef::try_from(graph_name)?))
         } else {
             None
         };
         py.allow_threads(|| {
-            if let Some(graph_format) = GraphFormat::from_media_type(mime_type) {
+            if let Some(from_graph_name) = &from_graph_name {
-                self.inner
+                self.inner.dump_graph(output, format, from_graph_name)
-                    .dump_graph(
-                        output,
-                        graph_format,
-                        &from_graph_name.unwrap_or(GraphName::DefaultGraph),
-                    )
-                    .map_err(map_serializer_error)
-            } else if let Some(dataset_format) = DatasetFormat::from_media_type(mime_type) {
-                if from_graph_name.is_some() {
-                    return Err(PyValueError::new_err(
-                        "The target graph name parameter is not available for dataset formats",
-                    ));
-                }
-                self.inner
-                    .dump_dataset(output, dataset_format)
-                    .map_err(map_serializer_error)
             } else {
-                Err(PyValueError::new_err(format!(
+                self.inner.dump_dataset(output, format)
-                    "Not supported MIME type: {mime_type}"
-                )))
             }
+            .map_err(map_serializer_error)
         })
     }
 
@@ -878,6 +867,7 @@ pub fn map_serializer_error(error: SerializerError) -> PyErr {
     match error {
         SerializerError::Storage(error) => map_storage_error(error),
         SerializerError::Io(error) => PyIOError::new_err(error.to_string()),
+        SerializerError::DatasetFormatExpected(_) => PyValueError::new_err(error.to_string()),
     }
 }
 

python/tests/test_store.py

@@ -321,8 +321,10 @@ class TestStore(unittest.TestCase):
         )
 
     def test_dump_with_io_error(self) -> None:
+        store = Store()
+        store.add(Quad(foo, bar, bar))
         with self.assertRaises(OSError) as _, TemporaryFile("rb") as fp:
-            Store().dump(fp, mime_type="application/rdf+xml")
+            store.dump(fp, mime_type="application/trig")
 
     def test_write_in_read(self) -> None:
         store = Store()

server/src/main.rs

@@ -1,10 +1,10 @@
 #![allow(clippy::print_stderr, clippy::cast_precision_loss, clippy::use_debug)]
-use anyhow::{anyhow, bail, Context, Error};
+use anyhow::{anyhow, bail, ensure, Context, Error};
 use clap::{Parser, Subcommand};
 use flate2::read::MultiGzDecoder;
 use oxhttp::model::{Body, HeaderName, HeaderValue, Method, Request, Response, Status};
 use oxhttp::Server;
-use oxigraph::io::{DatasetFormat, DatasetSerializer, GraphFormat, GraphSerializer};
+use oxigraph::io::{DatasetFormat, GraphFormat, RdfFormat, RdfSerializer};
 use oxigraph::model::{
     GraphName, GraphNameRef, IriParseError, NamedNode, NamedNodeRef, NamedOrBlankNode,
 };
@@ -424,9 +424,9 @@ pub fn main() -> anyhow::Result<()> {
                     .ok_or_else(|| anyhow!("The --location argument is required"))?,
             )?;
             let format = if let Some(format) = format {
-                GraphOrDatasetFormat::from_str(&format)?
+                rdf_format_from_name(&format)?
             } else if let Some(file) = &file {
-                GraphOrDatasetFormat::from_path(file)?
+                rdf_format_from_path(file)?
             } else {
                 bail!("The --format option must be set when writing to stdout")
             };
@@ -554,34 +554,25 @@ pub fn main() -> anyhow::Result<()> {
                         }
                     }
                     QueryResults::Graph(triples) => {
-                        let format = if let Some(name) = results_format {
+                        let format = if let Some(name) = &results_format {
-                            if let Some(format) = GraphFormat::from_extension(&name) {
+                            rdf_format_from_name(name)
-                                format
-                            } else if let Some(format) = GraphFormat::from_media_type(&name) {
-                                format
-                            } else {
-                                bail!("The file format '{name}' is unknown")
-                            }
                         } else if let Some(results_file) = &results_file {
-                            format_from_path(results_file, |ext| {
+                            rdf_format_from_path(results_file)
-                                GraphFormat::from_extension(ext)
-                                    .ok_or_else(|| anyhow!("The file extension '{ext}' is unknown"))
-                            })?
                         } else {
                             bail!("The --results-format option must be set when writing to stdout")
-                        };
+                        }?;
+                        let serializer = RdfSerializer::from_format(format);
                         if let Some(results_file) = results_file {
-                            let mut writer = GraphSerializer::from_format(format)
+                            let mut writer = serializer
-                                .triple_writer(BufWriter::new(File::create(results_file)?));
+                                .serialize_to_write(BufWriter::new(File::create(results_file)?));
                             for triple in triples {
-                                writer.write(triple?.as_ref())?;
+                                writer.write_triple(triple?.as_ref())?;
                             }
                             writer.finish()?;
                         } else {
-                            let mut writer =
+                            let mut writer = serializer.serialize_to_write(stdout().lock());
-                                GraphSerializer::from_format(format).triple_writer(stdout().lock());
                             for triple in triples {
-                                writer.write(triple?.as_ref())?;
+                                writer.write_triple(triple?.as_ref())?;
                             }
                             writer.finish()?;
                         }
@@ -670,22 +661,15 @@ fn bulk_load(
 fn dump(
     store: &Store,
     writer: impl Write,
-    format: GraphOrDatasetFormat,
+    format: RdfFormat,
     to_graph_name: Option<GraphName>,
 ) -> anyhow::Result<()> {
-    match format {
+    ensure!(format.supports_datasets() || to_graph_name.is_some(), "The --graph option is required when writing a format not supporting datasets like NTriples, Turtle or RDF/XML");
-        GraphOrDatasetFormat::Graph(format) => store.dump_graph(
+    if let Some(to_graph_name) = &to_graph_name {
-            writer,
+        store.dump_graph(writer, format, to_graph_name)
-            format,
+    } else {
-            &to_graph_name.ok_or_else(|| anyhow!("The --graph option is required when writing a graph format like NTriples, Turtle or RDF/XML"))?,
+        store.dump_dataset(writer, format)
-        )?,
+    }?;
-        GraphOrDatasetFormat::Dataset(format) => {
-            if to_graph_name.is_some() {
-                bail!("The --graph option is not allowed when writing a dataset format like NQuads or TriG");
-            }
-            store.dump_dataset(writer, format)?
-        }
-    }
     Ok(())
 }
 
@@ -761,6 +745,23 @@ impl FromStr for GraphOrDatasetFormat {
     }
 }
 
+fn rdf_format_from_path(path: &Path) -> anyhow::Result<RdfFormat> {
+    format_from_path(path, |ext| {
+        RdfFormat::from_extension(ext)
+            .ok_or_else(|| anyhow!("The file extension '{ext}' is unknown"))
+    })
+}
+
+fn rdf_format_from_name(name: &str) -> anyhow::Result<RdfFormat> {
+    if let Some(t) = RdfFormat::from_extension(name) {
+        return Ok(t);
+    }
+    if let Some(t) = RdfFormat::from_media_type(name) {
+        return Ok(t);
+    }
+    bail!("The file format '{name}' is unknown")
+}
+
 fn serve(store: Store, bind: String, read_only: bool, cors: bool) -> anyhow::Result<()> {
     let mut server = if cors {
         Server::new(cors_middleware(move |request| {
@@ -917,8 +918,9 @@ fn handle_request(
         (path, "GET") if path.starts_with("/store") => {
             if let Some(target) = store_target(request)? {
                 assert_that_graph_exists(&store, &target)?;
-                let format = graph_content_negotiation(request)?;
+                let format = rdf_content_negotiation(request)?;
-                let triples = store.quads_for_pattern(
+
+                let quads = store.quads_for_pattern(
                     None,
                     None,
                     None,
@@ -927,14 +929,14 @@ fn handle_request(
                 ReadForWrite::build_response(
                     move |w| {
                         Ok((
-                            GraphSerializer::from_format(format).triple_writer(w),
+                            RdfSerializer::from_format(format).serialize_to_write(w),
-                            triples,
+                            quads,
                         ))
                     },
-                    |(mut writer, mut triples)| {
+                    |(mut writer, mut quads)| {
-                        Ok(if let Some(t) = triples.next() {
+                        Ok(if let Some(q) = quads.next() {
-                            writer.write(&t?.into())?;
+                            writer.write_triple(&q?.into())?;
-                            Some((writer, triples))
+                            Some((writer, quads))
                         } else {
                             writer.finish()?;
                             None
@@ -943,17 +945,22 @@ fn handle_request(
                     format.media_type(),
                 )
             } else {
-                let format = dataset_content_negotiation(request)?;
+                let format = rdf_content_negotiation(request)?;
+                if !format.supports_datasets() {
+                    return Err(bad_request(format!(
+                        "It is not possible to serialize the full RDF dataset using {format} that does not support named graphs"
+                    )));
+                }
                 ReadForWrite::build_response(
                     move |w| {
                         Ok((
-                            DatasetSerializer::from_format(format).quad_writer(w),
+                            RdfSerializer::from_format(format).serialize_to_write(w),
                             store.iter(),
                         ))
                     },
                     |(mut writer, mut quads)| {
                         Ok(if let Some(q) = quads.next() {
-                            writer.write(&q?)?;
+                            writer.write_quad(&q?)?;
                             Some((writer, quads))
                         } else {
                             writer.finish()?;
@@ -1227,17 +1234,17 @@ fn evaluate_sparql_query(
                 .with_body(body))
         }
         QueryResults::Graph(triples) => {
-            let format = graph_content_negotiation(request)?;
+            let format = rdf_content_negotiation(request)?;
             ReadForWrite::build_response(
                 move |w| {
                     Ok((
-                        GraphSerializer::from_format(format).triple_writer(w),
+                        RdfSerializer::from_format(format).serialize_to_write(w),
                         triples,
                     ))
                 },
                 |(mut writer, mut triples)| {
                     Ok(if let Some(t) = triples.next() {
-                        writer.write(&t?)?;
+                        writer.write_triple(&t?)?;
                         Some((writer, triples))
                     } else {
                         writer.finish()?;
@@ -1403,26 +1410,26 @@ impl From<NamedGraphName> for GraphName {
     }
 }
 
-fn graph_content_negotiation(request: &Request) -> Result<GraphFormat, HttpError> {
+fn rdf_content_negotiation(request: &Request) -> Result<RdfFormat, HttpError> {
-    content_negotiation(
-        request,
-        &[
-            GraphFormat::NTriples.media_type(),
-            GraphFormat::Turtle.media_type(),
-            GraphFormat::RdfXml.media_type(),
-        ],
-        GraphFormat::from_media_type,
-    )
-}
-
-fn dataset_content_negotiation(request: &Request) -> Result<DatasetFormat, HttpError> {
     content_negotiation(
         request,
         &[
-            DatasetFormat::NQuads.media_type(),
+            "application/n-quads",
-            DatasetFormat::TriG.media_type(),
+            "application/n-triples",
+            "application/rdf+xml",
+            "application/trig",
+            "application/turtle",
+            "application/xml",
+            "application/x-trig",
+            "application/x-turtle",
+            "text/n3",
+            "text/nquads",
+            "text/plain",
+            "text/turtle",
+            "text/xml",
+            "text/x-nquads",
         ],
-        DatasetFormat::from_media_type,
+        RdfFormat::from_media_type,
     )
 }
 
@@ -1430,10 +1437,15 @@ fn query_results_content_negotiation(request: &Request) -> Result<QueryResultsFo
     content_negotiation(
         request,
         &[
-            QueryResultsFormat::Json.media_type(),
+            "application/json",
-            QueryResultsFormat::Xml.media_type(),
+            "application/sparql-results+json",
-            QueryResultsFormat::Csv.media_type(),
+            "application/sparql-results+xml",
-            QueryResultsFormat::Tsv.media_type(),
+            "application/xml",
+            "text/csv",
+            "text/json",
+            "text/tab-separated-values",
+            "text/tsv",
+            "text/xml",
         ],
         QueryResultsFormat::from_media_type,
     )