Promisify ldp#exists

Author: rubensworks

lib/handlers/allow.js

@@ -6,7 +6,7 @@ const debug = require('../debug.js').ACL
 const LegacyResourceMapper = require('../legacy-resource-mapper')
 
 function allow (mode) {
-  return function allowHandler (req, res, next) {
+  return async function allowHandler (req, res, next) {
     const ldp = req.app.locals.ldp || {}
     if (!ldp.webid) {
       return next()
@@ -27,37 +27,41 @@ function allow (mode) {
       : req.path
 
     // Check whether the resource exists
-    ldp.exists(req.hostname, reqPath, (err, ret) => {
-      // Ensure directories always end in a slash
-      const stat = err ? null : ret.stream
-      if (!reqPath.endsWith('/') && stat && stat.isDirectory()) {
-        reqPath += '/'
-      }
+    let stat
+    try {
+      const ret = await ldp.exists(req.hostname, reqPath)
+      stat = ret.stream
+    } catch (err) {
+      stat = null
+    }
 
-      // Obtain and store the ACL of the requested resource
-      req.acl = new ACL(rootUrl + reqPath, {
-        origin: req.get('origin'),
-        host: req.protocol + '://' + req.get('host'),
-        fetch: fetchFromLdp(mapper, ldp),
-        fetchGraph: (uri, options) => {
-          // first try loading from local fs
-          return ldp.getGraph(uri, options.contentType)
-            // failing that, fetch remote graph
-            .catch(() => ldp.fetchGraph(uri, options))
-        },
-        suffix: ldp.suffixAcl,
-        strictOrigin: ldp.strictOrigin,
-        originsAllowed: ldp.originsAllowed
-      })
+    // Ensure directories always end in a slash
+    if (!reqPath.endsWith('/') && stat && stat.isDirectory()) {
+      reqPath += '/'
+    }
 
-      // Ensure the user has the required permission
-      const userId = req.session.userId
-      req.acl.can(userId, mode)
-        .then(() => next(), err => {
-          debug(`${mode} access denied to ${userId || '(none)'}`)
-          next(err)
-        })
+    // Obtain and store the ACL of the requested resource
+    req.acl = new ACL(rootUrl + reqPath, {
+      origin: req.get('origin'),
+      host: req.protocol + '://' + req.get('host'),
+      fetch: fetchFromLdp(mapper, ldp),
+      fetchGraph: (uri, options) => {
+        // first try loading from local fs
+        return ldp.getGraph(uri, options.contentType)
+        // failing that, fetch remote graph
+          .catch(() => ldp.fetchGraph(uri, options))
+      },
+      suffix: ldp.suffixAcl,
+      strictOrigin: ldp.strictOrigin
     })
+
+    // Ensure the user has the required permission
+    const userId = req.session.userId
+    req.acl.can(userId, mode)
+      .then(() => next(), err => {
+        debug(`${mode} access denied to ${userId || '(none)'}`)
+        next(err)
+      })
   }
 }
 

lib/handlers/index.js

@@ -5,14 +5,15 @@ const debug = require('debug')('solid:index')
 const utils = require('../utils')
 const Negotiator = require('negotiator')
 
-function handler (req, res, next) {
+async function handler (req, res, next) {
   const indexFile = 'index.html'
   const ldp = req.app.locals.ldp
   const negotiator = new Negotiator(req)
   const requestedType = negotiator.mediaType()
   const filename = utils.reqToPath(req)
 
-  ldp.stat(filename).then(stats => {
+  try {
+    const stats = await ldp.stat(filename)
     if (!stats.isDirectory()) {
       return next()
     }
@@ -27,13 +28,11 @@ function handler (req, res, next) {
     debug('Looking for index in ' + req.path)
 
     // Check if file exists in first place
-    ldp.exists(req.hostname, path.join(req.path, indexFile), function (err) {
-      if (err) {
-        return next()
-      }
-      res.locals.path = path.join(req.path, indexFile)
-      debug('Found an index for current path')
-      return next()
-    })
-  }, () => next())
+    await ldp.exists(req.hostname, path.join(req.path, indexFile))
+    res.locals.path = path.join(req.path, indexFile)
+    debug('Found an index for current path')
+    return next()
+  } catch (e) {
+    next()
+  }
 }

lib/handlers/post.js

@@ -8,7 +8,7 @@ const patch = require('./patch')
 const error = require('../http-error')
 const { extensions } = require('mime-types')
 
-function handler (req, res, next) {
+async function handler (req, res, next) {
   const ldp = req.app.locals.ldp
   const contentType = req.get('content-type')
   debug('content-type is ', contentType)
@@ -26,29 +26,28 @@ function handler (req, res, next) {
   }
 
   // Check if container exists
-  ldp.exists(req.hostname, containerPath, function (err, ret) {
-    if (err) {
-      return next(error(err, 'Container not valid'))
-    }
-
-    let stats
+  let stats
+  try {
+    const ret = await ldp.exists(req.hostname, containerPath)
     if (ret) {
       stats = ret.stream
     }
+  } catch (err) {
+    return next(error(err, 'Container not valid'))
+  }
 
-    // Check if container is a directory
-    if (stats && !stats.isDirectory()) {
-      debug('Path is not a container, 405!')
-      return next(error(405, 'Requested resource is not a container'))
-    }
+  // Check if container is a directory
+  if (stats && !stats.isDirectory()) {
+    debug('Path is not a container, 405!')
+    return next(error(405, 'Requested resource is not a container'))
+  }
 
-    // Dispatch to the right handler
-    if (req.is('multipart/form-data')) {
-      multi()
-    } else {
-      one()
-    }
-  })
+  // Dispatch to the right handler
+  if (req.is('multipart/form-data')) {
+    multi()
+  } else {
+    one()
+  }
 
   function multi () {
     debug('receving multiple files')

lib/ldp.js

@@ -262,13 +262,10 @@ class LDP {
     })
   }
 
-  exists (hostname, path, callback) {
+  async exists (hostname, path) {
     const options = { hostname, path, includeBody: false }
-    if (callback) {
-      return this.get(options).then((data) => callback(null, data), callback)
-    } else {
-      return this.get(options).then(() => true)
-    }
+    await this.get(options)
+    return true
   }
 
   /**

lib/models/account-manager.js

@@ -107,16 +107,12 @@ class AccountManager {
    *
    * @return {Promise<boolean>}
    */
-  accountUriExists (accountUri, accountResource = '/') {
-    return new Promise((resolve, reject) => {
-      this.store.exists(accountUri, accountResource, (err, result) => {
-        if (err && err.status === 404) {
-          return resolve(false)
-        }
-
-        resolve(!!result)
-      })
-    })
+  async accountUriExists (accountUri, accountResource = '/') {
+    try {
+      return await this.store.exists(accountUri, accountResource)
+    } catch (err) {
+      return false
+    }
   }
 
   /**