add app.grantsRequired

lib/apis.js

@@ -157,6 +157,44 @@ module.exports.create = function (xconfx, apiFactories, apiDeps) {
         myApp = express();
         myApp.handlePromise = require('./common').promisableRequest;
         myApp.handleRejection = require('./common').rejectableRequest;
+        myApp.grantsRequired = function (grants) {
+          if (!Array.isArray(grants)) {
+            throw new Error("Usage: app.grantsRequired([ 'name|altname|altname2', 'othergrant' ])");
+          }
+
+          if (!grants.length) {
+            return function (req, res, next) {
+              next();
+            };
+          }
+
+          return function (req, res, next) {
+            if (!(req.oauth3 || req.oauth3.token)) {
+              // TODO some error generator for standard messages
+              res.send({ error: { message: "You must be logged in", code: "E_NO_AUTHN" } });
+              return;
+            }
+            if ('string' !== req.oauth3.token.scp) {
+              res.send({ error: { message: "Token must contain a grants string in 'scp'", code: "E_NO_GRANTS" } });
+              return;
+            }
+
+            // every grant in the array must be present
+            if (!grants.every(function (grant) {
+              var scopes = grant.split(/\|/g);
+              return scopes.some(function (scp) {
+                return req.oauth3.token.scp.split(/[,\s]+/mg).some(function (s) {
+                  return scp === s;
+                });
+              });
+            })) {
+              res.send({ error: { message: "Token does not contain valid grants: '" + grants + "'", code: "E_NO_GRANTS" } });
+              return;
+            }
+
+            next();
+          };
+        };
 
         var _getOauth3Controllers = pkgDeps.getOauth3Controllers = require('oauthcommon/example-oauthmodels').create(
           { sqlite3Sock: xconfx.sqlite3Sock, ipcKey: xconfx.ipcKey }