Allow linksHandler to map resources that do (not) exist yet

Author: rubensworks

lib/header.js

@@ -43,7 +43,19 @@ function addLinks (res, fileMetadata) {
 
 async function linksHandler (req, res, next) {
   const ldp = req.app.locals.ldp
-  const { path: filename } = await ldp.resourceMapper.mapUrlToFile(req)
+  let filename
+  try {
+    // Hack: createIfNotExists is set to true for PUT or PATCH requests
+    // because the file does not exist yet at this point.
+    // But it will be created afterwards.
+    // This should be improved with the new server architecture.
+    ({ path: filename } = await ldp.resourceMapper
+      .mapUrlToFile({ url: req, createIfNotExists: req.method === 'PUT' || req.method === 'PATCH' }))
+  } catch (e) {
+    // Silently ignore errors here
+    // Later handlers will error as well, but they will be able to given a more concrete error message (like 400 or 404)
+    return next()
+  }
 
   if (path.extname(filename) === ldp.suffixMeta) {
     debug.metadata('Trying to access metadata file as regular file.')