From 535e5e30536b5ff9837de746936cff0ee13873c8 Mon Sep 17 00:00:00 2001
From: Tpt <thomaspt@hotmail.fr>
Date: Sat, 15 Aug 2020 22:51:01 +0200
Subject: [PATCH] Adds .update() and .dump() to JavaScript bindings

---
 js/README.md     | 28 ++++++++++++++++++++++++++++
 js/src/store.rs  | 36 ++++++++++++++++++++++++++++++++++++
 js/test/store.js | 37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 101 insertions(+)

diff --git a/js/README.md b/js/README.md
index d679c948..641982a2 100644
--- a/js/README.md
+++ b/js/README.md
@@ -135,6 +135,14 @@ if (store.query("ASK { ?s ?s ?s }")) {
 }
 ```
 
+#### `MemoryStore.prototype.update(String query)`
+Executes a [SPARQL 1.1 Update](https://www.w3.org/TR/sparql11-update/).
+
+Example of update:
+```js
+store.update("DELETE WHERE { <http://example.com/s> ?p ?o }")
+```
+
 ### `MemoryStore.prototype.load(String data, String mimeType, NamedNode|String? baseIRI, NamedNode|BlankNode|DefaultGraph? toNamedGraph)`
 
 Loads serialized RDF triples or quad into the store.
@@ -157,6 +165,26 @@ store.load("<http://example.com> <http://example.com> <> .", "text/turtle", "htt
 ```
 
 
+### `MemoryStore.prototype.dump(String mimeType, NamedNode|BlankNode|DefaultGraph? fromNamedGraph)`
+
+Returns serialized RDF triples or quad from the store.
+The method arguments are:
+1. `mimeType`: the MIME type of the serialization. See below for the supported mime types.
+2. `fromNamedGraph`: for triple serialization formats, the name of the named graph the triple should be loaded from.
+
+The available formats are:
+* [Turtle](https://www.w3.org/TR/turtle/): `text/turtle`
+* [TriG](https://www.w3.org/TR/trig/): `application/trig`
+* [N-Triples](https://www.w3.org/TR/n-triples/): `application/n-triples`
+* [N-Quads](https://www.w3.org/TR/n-quads/): `application/n-quads`
+* [RDF/XML](https://www.w3.org/TR/rdf-syntax-grammar/): `application/rdf+xml`
+
+Example of building a Turtle file from the named graph `<http://example.com/graph>`:
+```js
+store.dump("text/turtle", store.dataFactory.namedNode("http://example.com/graph"));
+```
+
+
 ## How to contribute
 
 The Oxigraph bindings are written in Rust using [the Rust WASM toolkit](https://rustwasm.github.io/docs.html).
diff --git a/js/src/store.rs b/js/src/store.rs
index 3b50772f..0fdf4728 100644
--- a/js/src/store.rs
+++ b/js/src/store.rs
@@ -137,6 +137,10 @@ impl JsMemoryStore {
         Ok(output)
     }
 
+    pub fn update(&self, update: &str) -> Result<(), JsValue> {
+        self.store.update(update).map_err(to_err)
+    }
+
     pub fn load(
         &self,
         data: &str,
@@ -185,4 +189,36 @@ impl JsMemoryStore {
             Err(format_err!("Not supported MIME type: {}", mime_type))
         }
     }
+
+    pub fn dump(&self, mime_type: &str, from_graph_name: &JsValue) -> Result<String, JsValue> {
+        let from_graph_name =
+            if let Some(graph_name) = self.from_js.to_optional_term(from_graph_name)? {
+                Some(graph_name.try_into()?)
+            } else {
+                None
+            };
+
+        let mut buffer = Vec::new();
+        if let Some(graph_format) = GraphFormat::from_media_type(mime_type) {
+            self.store
+                .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));
+        }
+        String::from_utf8(buffer).map_err(to_err)
+    }
 }
diff --git a/js/test/store.js b/js/test/store.js
index 80a1ccae..aca406a7 100644
--- a/js/test/store.js
+++ b/js/test/store.js
@@ -79,6 +79,26 @@ describe('MemoryStore', function () {
     })
   })
 
+  describe('#update()', function () {
+    it('INSERT DATA', function () {
+      const store = new MemoryStore()
+      store.update('INSERT DATA { <http://example.com> <http://example.com> <http://example.com> }')
+      assert.strictEqual(1, store.size)
+    })
+
+    it('DELETE DATA', function () {
+      const store = new MemoryStore([dataFactory.triple(ex, ex, ex)])
+      store.update('DELETE DATA { <http://example.com> <http://example.com> <http://example.com> }')
+      assert.strictEqual(0, store.size)
+    })
+
+    it('DELETE WHERE', function () {
+      const store = new MemoryStore([dataFactory.triple(ex, ex, ex)])
+      store.update('DELETE WHERE { ?v ?v ?v }')
+      assert.strictEqual(0, store.size)
+    })
+  })
+
   describe('#load()', function () {
     it('load NTriples in the default graph', function () {
       const store = new MemoryStore()
@@ -110,4 +130,21 @@ describe('MemoryStore', function () {
       assert(store.has(dataFactory.quad(ex, ex, ex, ex)))
     })
   })
+
+  describe('#dump()', function () {
+    it('dump dataset content', function () {
+      const store = new MemoryStore([dataFactory.quad(ex, ex, ex, ex)])
+      assert.strictEqual('<http://example.com> <http://example.com> <http://example.com> <http://example.com> .\n', store.dump('application/n-quads'))
+    })
+
+    it('dump named graph content', function () {
+      const store = new MemoryStore([dataFactory.quad(ex, ex, ex, ex)])
+      assert.strictEqual('<http://example.com> <http://example.com> <http://example.com> .\n', store.dump('application/n-triples', ex))
+    })
+
+    it('dump default graph content', function () {
+      const store = new MemoryStore([dataFactory.quad(ex, ex, ex, ex)])
+      assert.strictEqual('', store.dump('application/n-triples'))
+    })
+  })
 })