Use same patch logic regardless of content type.

Author: RubenVerborgh

lib/handlers/patch.js

@@ -4,11 +4,14 @@ var mime = require('mime-types')
 var debug = require('../debug').handlers
 var utils = require('../utils.js')
 var error = require('../http-error')
-const sparqlPatch = require('./patch/sparql-patcher.js')
-const sparqlUpdatePatch = require('./patch/sparql-update-patcher.js')
 
 const DEFAULT_CONTENT_TYPE = 'text/turtle'
 
+const PATCHERS = {
+  'application/sparql': require('./patch/sparql-patcher.js'),
+  'application/sparql-update': require('./patch/sparql-update-patcher.js')
+}
+
 function handler (req, res, next) {
   req.setEncoding('utf8')
   req.text = ''
@@ -37,26 +40,16 @@ function patchHandler (req, res, next) {
 
   debug('PATCH -- Content-type ' + patchContentType + ' patching target ' + targetContentType + ' <' + targetURI + '>')
 
-  if (patchContentType === 'application/sparql') {
-    sparqlPatch(filename, targetURI, req.text, function (err, result) {
-      if (err) {
-        return next(err)
-      }
-      res.json(result)
-      return next()
-    })
-  } else if (patchContentType === 'application/sparql-update') {
-    return sparqlUpdatePatch(filename, targetURI, req.text, function (err, patchKB) {
-      if (err) {
-        return next(err)
-      }
-
-      // subscription.publishDelta(req, res, patchKB, targetURI)
-      debug('PATCH -- applied OK (sync)')
-      res.send('Patch applied OK\n')
-      return next()
-    })
-  } else {
+  const patch = PATCHERS[patchContentType]
+  if (!patch) {
     return next(error(400, 'Unknown patch content type: ' + patchContentType))
   }
-} // postOrPatch
+  patch(filename, targetURI, req.text, function (err, result) {
+    if (err) {
+      next(err)
+    } else {
+      res.send(result)
+      next()
+    }
+  })
+}

lib/handlers/patch/sparql-patcher.js

@@ -56,7 +56,7 @@ function patch (filename, targetURI, text, callback) {
 
     var onDone = function () {
       debug('PATCH -- Query done, no. bindings: ' + bindingsArray.length)
-      return callback(null, {
+      const result = {
         'head': {
           'vars': query.vars.map(function (v) {
             return v.toNT()
@@ -65,7 +65,8 @@ function patch (filename, targetURI, text, callback) {
         'results': {
           'bindings': bindingsArray
         }
-      })
+      }
+      callback(null, JSON.stringify(result))
     }
 
     var fetcher = new $rdf.Fetcher(targetKB, 10000, true)

lib/handlers/patch/sparql-update-patcher.js

@@ -71,7 +71,7 @@ function patch (filename, targetURI, text, callback) {
               return cb(error(500, 'Failed to write file back after patch: ' + err))
             }
             debug('PATCH -- applied OK (sync)')
-            return cb(null, patchKB)
+            return cb(null, 'Patch applied OK\n')
           })
         })
       })