Improves documentation

lib/src/lib.rs

@@ -1,3 +1,13 @@
+//! This crate is a work in progress of implementation of an RDF and SPARQL software stack in Rust.
+//!
+//! Its goal is to provide a compliant, safe and fast implementation of W3C specifications.
+//!
+//! It currently provides:
+//! * Basic RDF data structures in the `model` package
+//! * Parsers for XML, Turtle and N-Triples syntaxes in the `rio` package
+//! * A memory based and a disk based stores in the `store` package
+//! * A work in progress SPARQL implementation in the `sparql` package
+
 #![cfg_attr(
     feature = "cargo-clippy",
     warn(

lib/src/model/dataset.rs

@@ -122,7 +122,8 @@ pub trait NamedGraph: Graph {
 /// assert_eq!(vec![triple.in_graph(None)], results);
 /// ```
 ///
-/// The implementation backed by RocksDB could be built using `RocksDbDataset::open` and works just like its in-memory equivalent:
+/// The implementation backed by RocksDB if disabled by default and requires the `"rocksdb"` feature to be activated.
+/// A `RocksDbDataset` could be built using `RocksDbDataset::open` and works just like its in-memory equivalent:
 /// ```ignore
 /// use rudf::store::RocksDbDataset;
 /// let dataset = RocksDbDataset::open("foo.db");

lib/src/model/literal.rs

@@ -131,7 +131,7 @@ impl Literal {
     }
 
     /// The literal [lexical form](https://www.w3.org/TR/rdf11-concepts/#dfn-lexical-form)
-    pub fn value(&self) -> Cow<String> {
+    pub fn value(&self) -> Cow<str> {
         match self.0 {
             LiteralContent::SimpleLiteral(ref value)
             | LiteralContent::String(ref value)

lib/src/rio/ntriples/mod.rs

@@ -1,4 +1,4 @@
-///Implements https://www.w3.org/TR/n-triples/
+//! Implementation of [N-Triples](https://www.w3.org/TR/n-triples/) RDF syntax
 
 mod grammar {
     #![cfg_attr(
@@ -67,7 +67,7 @@ impl<R: Read> Iterator for NTriplesIterator<R> {
     }
 }
 
-/// Reads a N-Triples file from a Rust `Read` and returns an iterator on the read `Triple`s
+/// Reads a [N-Triples](https://www.w3.org/TR/n-triples/) file from a Rust `Read` and returns an iterator of the read `Triple`s
 pub fn read_ntriples<'a, R: Read + 'a>(source: R) -> impl Iterator<Item = Result<Triple>> {
     NTriplesIterator {
         buffer: String::default(),

lib/src/rio/turtle/mod.rs

@@ -1,4 +1,4 @@
-/// Implements https://www.w3.org/TR/turtle/
+//! Implementation of [Turtle](https://www.w3.org/TR/turtle/) RDF syntax
 
 mod grammar {
     #![cfg_attr(
@@ -39,9 +39,10 @@ mod grammar {
         }
     }
 
-    /// Reads a Turtle file from a Rust `Read` and returns an iterator on the read `Triple`s
+    /// Reads a [Turtle](https://www.w3.org/TR/turtle/) file from a Rust `Read` and returns an iterator on the read `Triple`s
     ///
-    /// Warning: this implementation has not been optimized yet and stores all the found triples in memory
+    /// Warning: this implementation has not been optimized yet and stores all the found triples in memory.
+    /// This implementation also requires that blank node ids are valid UTF-8
     pub fn read_turtle<'a, R: Read + 'a>(
         source: R,
         base_uri: impl Into<Option<Url>>,

lib/src/rio/xml.rs

@@ -1,3 +1,5 @@
+//! Implementation of [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/) syntax
+
 use model::vocab::rdf;
 use model::Triple;
 use model::*;
@@ -12,7 +14,9 @@ use std::str::FromStr;
 use url::Url;
 use Result;
 
-/// Reads a RDF/XML file from a Rust `Read` and returns an iterator on the read `Triple`s
+/// Reads a [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/) file from a Rust `Read` and returns an iterator on the read `Triple`s
+///
+/// Warning: The `rdf:parseType="Literal"` and `rdf:parseType="Collection"` options are not supported yet
 pub fn read_rdf_xml(
     source: impl BufRead,
     base_uri: impl Into<Option<Url>>,

lib/src/sparql/algebra.rs

@@ -1,3 +1,5 @@
+//! [SPARQL 1.1 Query Algebra](https://www.w3.org/TR/sparql11-query/#sparqlQuery) AST
+
 use model::*;
 use std::collections::BTreeMap;
 use std::collections::BTreeSet;

lib/src/sparql/mod.rs

@@ -1,5 +1,27 @@
-//! SPARQL 1.1 implementation.
+//! [SPARQL](https://www.w3.org/TR/sparql11-overview/) implementation.
-//! This is a work in progress!!!
+//!
+//! The support of RDF Dataset and SPARQL 1.1 specific features is not done yet.
+//!
+//! This module adds query capabilities to the `rudf::model::Dataset` implementations.
+//!
+//! Usage example:
+//! ```
+//! use rudf::model::*;
+//! use rudf::store::MemoryDataset;
+//! use rudf::sparql::SparqlDataset;
+//! use rudf::sparql::PreparedQuery;
+//! use rudf::sparql::algebra::QueryResult;
+//! use std::str::FromStr;
+//!
+//! let dataset = MemoryDataset::default();
+//! let ex = NamedNode::from_str("http://example.com").unwrap();
+//! dataset.insert(&Quad::new(ex.clone(), ex.clone(), ex.clone(), None));
+//! let prepared_query = dataset.prepare_query("SELECT ?s WHERE { ?s ?p ?o }".as_bytes()).unwrap();
+//! let results = prepared_query.exec().unwrap();
+//! if let QueryResult::Bindings(results) = results {
+//!     assert_eq!(results.into_values_iter().next().unwrap().unwrap()[0], Some(ex.into()));
+//! }
+//! ```
 
 use model::Dataset;
 use sparql::algebra::Query;
@@ -21,12 +43,21 @@ pub mod parser;
 mod plan;
 pub mod xml_results;
 
+/// An extension of the `rudf::model::Dataset` trait to allow SPARQL operations on it.
+///
+/// It is implemented by all stores provided by Rudf
 pub trait SparqlDataset: Dataset {
     type PreparedQuery: PreparedQuery;
+
+    /// Prepares a [SPARQL 1.1](https://www.w3.org/TR/sparql11-query/) query and returns an object that could be used to execute it
+    ///
+    /// The implementation is a work in progress, RDF Dataset and SPARQL 1.1 specific features are not implemented yet.
     fn prepare_query(&self, query: impl Read) -> Result<Self::PreparedQuery>;
 }
 
+/// A prepared [SPARQL 1.1](https://www.w3.org/TR/sparql11-query/) query
 pub trait PreparedQuery {
+    /// Evaluates the query and returns its results
     fn exec(&self) -> Result<QueryResult>;
 }
 
@@ -34,11 +65,11 @@ impl<S: EncodedQuadsStore> SparqlDataset for StoreDataset<S> {
     type PreparedQuery = SimplePreparedQuery<S>;
 
     fn prepare_query(&self, query: impl Read) -> Result<SimplePreparedQuery<S>> {
-        Ok(match read_sparql_query(query, None)? {
+        Ok(SimplePreparedQuery(match read_sparql_query(query, None)? {
             Query::Select { algebra, dataset } => {
                 let store = self.encoded();
                 let (plan, variables) = PlanBuilder::build(&*store, &algebra)?;
-                SimplePreparedQuery::Select {
+                SimplePreparedQueryOptions::Select {
                     plan,
                     variables,
                     evaluator: SimpleEvaluator::new(store),
@@ -47,7 +78,7 @@ impl<S: EncodedQuadsStore> SparqlDataset for StoreDataset<S> {
             Query::Ask { algebra, dataset } => {
                 let store = self.encoded();
                 let (plan, _) = PlanBuilder::build(&*store, &algebra)?;
-                SimplePreparedQuery::Ask {
+                SimplePreparedQueryOptions::Ask {
                     plan,
                     evaluator: SimpleEvaluator::new(store),
                 }
@@ -59,7 +90,7 @@ impl<S: EncodedQuadsStore> SparqlDataset for StoreDataset<S> {
             } => {
                 let store = self.encoded();
                 let (plan, variables) = PlanBuilder::build(&*store, &algebra)?;
-                SimplePreparedQuery::Construct {
+                SimplePreparedQueryOptions::Construct {
                     plan,
                     construct: PlanBuilder::build_graph_template(&*store, &construct, variables)?,
                     evaluator: SimpleEvaluator::new(store),
@@ -68,16 +99,19 @@ impl<S: EncodedQuadsStore> SparqlDataset for StoreDataset<S> {
             Query::Describe { algebra, dataset } => {
                 let store = self.encoded();
                 let (plan, _) = PlanBuilder::build(&*store, &algebra)?;
-                SimplePreparedQuery::Describe {
+                SimplePreparedQueryOptions::Describe {
                     plan,
                     evaluator: SimpleEvaluator::new(store),
                 }
             }
-        })
+        }))
     }
 }
 
-pub enum SimplePreparedQuery<S: EncodedQuadsStore> {
+/// An implementation of `PreparedQuery` for internal use
+pub struct SimplePreparedQuery<S: EncodedQuadsStore>(SimplePreparedQueryOptions<S>);
+
+enum SimplePreparedQueryOptions<S: EncodedQuadsStore> {
     Select {
         plan: PlanNode,
         variables: Vec<Variable>,
@@ -100,19 +134,21 @@ pub enum SimplePreparedQuery<S: EncodedQuadsStore> {
 
 impl<S: EncodedQuadsStore> PreparedQuery for SimplePreparedQuery<S> {
     fn exec(&self) -> Result<QueryResult> {
-        match self {
+        match &self.0 {
-            SimplePreparedQuery::Select {
+            SimplePreparedQueryOptions::Select {
                 plan,
                 variables,
                 evaluator,
             } => evaluator.evaluate_select_plan(&plan, &variables),
-            SimplePreparedQuery::Ask { plan, evaluator } => evaluator.evaluate_ask_plan(&plan),
+            SimplePreparedQueryOptions::Ask { plan, evaluator } => {
-            SimplePreparedQuery::Construct {
+                evaluator.evaluate_ask_plan(&plan)
+            }
+            SimplePreparedQueryOptions::Construct {
                 plan,
                 construct,
                 evaluator,
             } => evaluator.evaluate_construct_plan(&plan, &construct),
-            SimplePreparedQuery::Describe { plan, evaluator } => {
+            SimplePreparedQueryOptions::Describe { plan, evaluator } => {
                 evaluator.evaluate_describe_plan(&plan)
             }
         }

lib/src/store/rocksdb.rs

@@ -20,6 +20,8 @@ use Result;
 
 /// `rudf::model::Dataset` trait implementation based on the [RocksDB](https://rocksdb.org/) key-value store
 ///
+/// To use it, the `"rocksdb"` feature need to be activated.
+///
 /// Usage example:
 /// ```
 /// use rudf::store::RocksDbDataset;

lib/src/utils.rs

@@ -2,13 +2,7 @@ pub trait Escaper {
     fn escape(&self) -> String;
 }
 
-impl<'a> Escaper for &'a str {
+impl Escaper for str {
-    fn escape(&self) -> String {
-        self.chars().flat_map(EscapeRDF::new).collect()
-    }
-}
-
-impl Escaper for String {
     fn escape(&self) -> String {
         self.chars().flat_map(EscapeRDF::new).collect()
     }