Refactored storage services abstract implementation

The implementation now expects an rdflib.js IndexedFormula to be the interface with the storage services. a db.read operation asynchronously returns an IndexedFormula for the resource.

Author: Jim Amsden

jsonld.js

@@ -22,11 +22,12 @@ function define(name, value) {
     Object.defineProperty(exports, name, {
         value:      value,
         enumerable: true
-    });
+    })
 }
 
-define('turtle', 'text/turtle');
-define('text', 'text/plain');
-define('n3', 'text/n3');
-define('jsonld', 'application/ld+json');
-define('json', 'application/json');
+define('turtle', 'text/turtle')
+define('text', 'text/plain')
+define('n3', 'text/n3')
+define('jsonld', 'application/ld+json')
+define('json', 'application/json')
+define('rdfxml', 'application/rdf+xml')

media.js

@@ -8,13 +8,14 @@
   "contributors": "Jim Amsden <jamsden@us.ibm.com>",
   "dependencies": {
     "express": "~4.16.3",
-    "n3": "~0.11.3",
     "jsonld": "~1.0.1",
+    "ldp-service-jena": "file:~/Developer/LDP/ldp-service-jena",
     "mongodb": "~3.0.7",
-    "ldp-service-mongodb": ""
+    "n3": "~1.0.0-alpha",
+    "rdflib": "^0.17.0"
   },
   "engines": {
-    "node": "~5.1.0"
+    "node": "~8.11.1"
   },
   "repository": {
     "type": "git",

package-lock.json

@@ -49,30 +49,52 @@ function ensureIndex() {
 }
 
 /*
- * Initialize the database
+ * Initialize the database. This could be done using
+ * the facilities of the DBMS and may not need to be implemented
+ * in all cases. It does provide a way to specify the env.dbName
+ * for the database you want to use, and makes sure the database
+ * exists and is initialized, possibly with at least one root
+ * container graph.
  */
 exports.init = function init(env, callback) {
-	throw "storage method init(env, callback) not implemented"
+	console.log("storage method init(env, callback) not implemented")
 }
 
+/*
+ * Drop an initialized database. This could be done using
+ * the facilities of the DBMS and may not need to be implemented
+ * in all cases. Implement this if you want init/drop to be able
+ * to dynamically create and remove databases. Don't implement
+ * it if you want the database to be already implemented outside
+ * the app.
+ */
 exports.drop = function drop(callback) {
-	throw "storage method drop(callback) not implemented"
+	console.log("storage method drop(callback) not implemented")
 }
 
+/*
+ * Used in create methods to reserve a URI for subsequent update. 
+ * Simply creates an empty graph.
+ */
 exports.reserveURI = function reserveURI(uri, callback) {
 	throw "storage method reserveURI(uri, callback) not implemented"
 }
 
+/*
+ * Releases a reserved URI that is no longer needed (i.e., the update
+ * will never be done)
+ */
 exports.releaseURI = function releaseURI(uri) {
 	throw "storage method releaseURI(uri) not implemented"
 }
 
-exports.put = function put(resource, callback) {
-	throw "storage method put(resource, callback) not implemented"
+
+exports.update = function update(resource, callback) {
+	throw "storage method uptate(resource, callback) not implemented"
 }
 
-exports.get = function get(uri, callback) {
-	throw "storage method get(uri, callback) not implemented"
+exports.read = function read(uri, callback) {
+	throw "storage method read(uri, callback) not implemented"
 }
 
 exports.remove = function remove(uri, callback) {

package.json

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2014 IBM Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Initializes the ldp-server and opens a client view for 
+ * accessing LDP resouces and displaying a graph of their links
+ */
+
+var express = require('express')
+var ldpService = require('../../ldp-service')
+
+// define a simple environment for testing
+var env = {
+	"scheme": "http",
+	"host": "localhost",
+	"port": 3000,
+	"context": "/r",
+	"storageImpl": "ldp-service-jena",
+	"jenaURL": "http://localhost:3030/mrm/",
+}
+
+// setup LDP middleware
+var app = express()
+app.use(express.static(__dirname + '/public'))
+
+// initialize database and set up LDP services and viz when ready
+app.use(ldpService(env))
+
+// error handling (developer centric)
+app.use(function(err, req, res, next){
+	console.error(err.stack)
+	res.send(500, 'Something broke!')
+})
+
+// Start server
+app.listen(env.port, env.host)
+console.log('App started on port ' + env.port)