Add support for SPARQL

There's support for sending SPARQL queries and importing various sets
of the library at this time.  Mostly query and update should be of
interest.

Author: madnificent

Dockerfile

@@ -11,6 +11,9 @@ COPY . /usr/src/app
 RUN ln -s /app/app.js /usr/src/app/
 RUN npm install
 
+ENV MU_SPARQL_ENDPOINT 'http://database:8890/sparql'
+ENV MU_APPLICATION_GRAPH 'http://mu.semte.ch/application'
+
 CMD sh boot.sh
 
 ONBUILD ADD . /app/

helpers/mu/index.js

@@ -1,8 +1,15 @@
 import app from './server';
+import sparql from './sparql';
 
 const mu = {
-  app: app
+  app: app,
+  sparql: sparql,
+  SPARQL: sparql.sparql,
+  query: sparql.query,
+  update: sparql.update,
 }
 
-export { app };
+const SPARQL = mu.SPARQL, query = mu.query, update = mu.update;
+
+export { app , sparql, SPARQL, query, update };
 export default mu;

helpers/mu/sparql.js

@@ -0,0 +1,35 @@
+import SC2 from 'sparql-client-2';
+const { SparqlClient, SPARQL } = SC2;
+
+//==-- logic --==//
+
+// builds a new sparqlClient
+function newSparqlClient() {
+  return new SparqlClient( process.env.MU_SPARQL_ENDPOINT ).register({
+    mu: 'http://mu.semte.ch/vocabularies/',
+    muCore: 'http://mu.semte.ch/vocabularies/core/',
+    muExt: 'http://mu.semte.ch/vocabularies/ext/'
+  });
+}
+
+// executes a query (you can use the template syntax)
+function query( queryString ){
+  return newSparqlClient().query( queryString ).execute();
+};
+
+// executes an update query
+const update = query;
+
+
+//==-- exports --==//
+const exports = {
+  newSparqlClient: newSparqlClient,
+  SPARQL: SPARQL,
+  sparql: SPARQL,
+  query: query,
+  update: update
+}
+export default exports;
+
+export { query, update, SPARQL as SPARQL, SPARQL as sparql, newSparqlClient };
+

package.json

@@ -21,7 +21,8 @@
     "babel-preset-es2015": "^6.18.0",
     "babel-preset-es2016": "^6.16.0",
     "babel-preset-es2017": "^6.16.0",
-    "supervisor": "^0.12.0"
+    "supervisor": "^0.12.0",
+    "sparql-client-2": "^0.6.0"
   },
   "author": "Aad Versteden <[email protected]>",
   "license": "MIT",