Allow patch handler to map resources that do no exist yet

Author: rubensworks

lib/handlers/patch.js

@@ -16,14 +16,24 @@ const PATCH_PARSERS = {
   'text/n3': require('./patch/n3-patch-parser.js')
 }
 
+const DEFAULT_CONTENT_TYPE = 'text/turtle'
+
 // Handles a PATCH request
 async function patchHandler (req, res, next) {
   debug(`PATCH -- ${req.originalUrl}`)
   res.header('MS-Author-Via', 'SPARQL')
   try {
     // Obtain details of the target resource
     const ldp = req.app.locals.ldp
-    const { path, contentType } = await ldp.resourceMapper.mapUrlToFile({ url: req })
+    let path, contentType;
+    try {
+      // First check if the file already exists
+      ({ path, contentType } = await ldp.resourceMapper.mapUrlToFile({ url: req }))
+    } catch (err) {
+      // If the file doesn't exist, request one to be created with the default content type
+      ({ path, contentType } = await ldp.resourceMapper.mapUrlToFile(
+        { url: req, createIfNotExists: true, contentType: DEFAULT_CONTENT_TYPE }))
+    }
     const { url } = await ldp.resourceMapper.mapFileToUrl({ path, hostname: req.hostname })
     const resource = { path, contentType, url }
     debug('PATCH -- Target <%s> (%s)', url, contentType)