Add patch functionality to lists

lib/routes/_lists.js

@@ -2,6 +2,7 @@
 
 const _ = require('lodash'),
   responses = require('../responses'),
+  controller = require('../services/lists'),
   { withAuthLevel, authLevels } = require('amphora-auth');
 
 /**
@@ -17,13 +18,24 @@ function onlyJSONLists(req, res, next) {
   }
 }
 
+/**
+ * Modify a list, return JSON
+ * @param {Object} req
+ * @param {Object} res
+ */
+function patchList(req, res) {
+  responses.expectJSON(() => controller.patchList(req.uri, req.body, res.locals), res);
+}
+
 function routes(router) {
   router.use(responses.varyWithoutExtension({varyBy: ['Accept']}));
   router.all('*', responses.acceptJSONOnly);
   router.all('/', responses.methodNotAllowed({allow: ['get']}));
   router.get('/', responses.list());
-  router.all('/:name', responses.methodNotAllowed({allow: ['get', 'put']}));
+  router.all('/:name', responses.methodNotAllowed({allow: ['get', 'put', 'patch']}));
   router.get('/:name', responses.getRouteFromDB);
+  router.patch('/:name', withAuthLevel(authLevels.WRITE));
+  router.patch('/:name', patchList);
   router.use('/:name', onlyJSONLists);
   router.put('/:name', withAuthLevel(authLevels.WRITE));
   router.put('/:name', responses.putRouteFromDB);
@@ -32,3 +44,4 @@ function routes(router) {
 
 module.exports = routes;
 module.exports.onlyJSONLists = onlyJSONLists;
+module.exports.patchList = patchList;

lib/routes/_lists.test.js

@@ -4,6 +4,7 @@ const _ = require('lodash'),
   filename = __filename.split('/').pop().split('.').shift(),
   lib = require('./' + filename),
   responses = require('../responses'),
+  controller = require('../services/lists'),
   sinon = require('sinon'),
   expect = require('chai').expect;
 
@@ -12,12 +13,24 @@ describe(_.startCase(filename), function () {
 
   beforeEach(function () {
     sandbox = sinon.sandbox.create();
+
+    sandbox.stub(controller, 'patchList');
   });
 
   afterEach(function () {
     sandbox.restore();
   });
 
+  describe('patchList', function () {
+    const fn = lib[this.title];
+
+    it('calls expectjson and lists.patchList', function () {
+      fn({}, { json: item => item });
+
+      expect(controller.patchList.called).to.equal(true);
+    });
+  });
+
   describe('onlyJSONLists', function () {
     const fn = lib[this.title];
 

lib/services/lists.js

@@ -0,0 +1,60 @@
+'use strict';
+
+const _isEqual = require('lodash/isEqual');
+
+let db = require('./db');
+
+/**
+ * Appends an entry to a list and returns the updated list.
+ * @param {Array<Object>} list
+ * @param {Array<Object>} data
+ * @returns {Array<Object>}
+ */
+function addToList(list, data) {
+  return list.concat(data);
+}
+
+/**
+ * Removes an entry from a list and returns the updated list.
+ * @param {Array<Object>} list
+ * @param {Array<Object>} data
+ * @returns {Array<Object>}
+ */
+function removeFromList(list, data) {
+  for (const deletion of data) {
+    list = list.filter(entry => !_isEqual(entry, deletion));
+  }
+
+  return list;
+}
+
+/**
+ * Add or Remove an item from a list
+ * @param {string} uri
+ * @param {Array<Object>} data
+ * @returns {Promise}
+ */
+function patchList(uri, data) {
+  if (!Array.isArray(data.add) && !Array.isArray(data.remove)) {
+    throw new Error('Bad Request. List PATCH requires `add` or `remove` to be an array.');
+  }
+
+  return db.get(uri).then(list => {
+    if (Array.isArray(data.add)) {
+      list = addToList(list, data.add);
+    }
+
+    if (Array.isArray(data.remove)) {
+      list = removeFromList(list, data.remove);
+    }
+
+    // db.put wraps result in an object `{ _value: list }`, return list only
+    // hopefully db.put never does anything to the data bc we're just returning list
+    return db.put(uri, list).then(() => list);
+  });
+}
+
+module.exports.patchList = patchList;
+
+// For testing
+module.exports.setDb = mock => db = mock;

lib/services/lists.test.js

@@ -0,0 +1,53 @@
+'use strict';
+
+const _ = require('lodash'),
+  filename = __filename.split('/').pop().split('.').shift(),
+  lib = require('./' + filename),
+  sinon = require('sinon'),
+  expect = require('chai').expect,
+  storage = require('../../test/fixtures/mocks/storage');
+
+describe(_.startCase(filename), function () {
+  let sandbox, db;
+
+  beforeEach(function () {
+    sandbox = sinon.sandbox.create();
+
+    db = storage();
+    lib.setDb(db);
+  });
+
+  afterEach(function () {
+    sandbox.restore();
+  });
+
+  describe('patchList', function () {
+    const fn = lib.patchList;
+
+    it('will throw if bad request body', function () {
+      try {
+        fn('domain.com/_lists/test', {});
+      } catch (e) {
+        expect(e.message).to.eql('Bad Request. List PATCH requires `add` or `remove` to be an array.');
+      }
+    });
+
+    it('adds to existing lists if has add property', function () {
+      db.get.resolves([]);
+      db.put.callsFake((uri, list) => Promise.resolve({ _value: list }));
+
+      return fn('domain.com/_lists/test', { add: [ 'hello' ] }).then(list => {
+        expect(list).to.eql([ 'hello' ]);
+      });
+    });
+
+    it('removes from existing lists if has remove property', function () {
+      db.get.resolves([ 'hello' ]);
+      db.put.callsFake((uri, list) => Promise.resolve({ _value: list }));
+
+      return fn('domain.com/_lists/test', { remove: [ 'hello' ] }).then(list => {
+        expect(list).to.eql([]);
+      });
+    });
+  });
+});

test/api/_lists/patch.js

@@ -0,0 +1,38 @@
+'use strict';
+
+const _ = require('lodash'),
+  apiAccepts = require('../../fixtures/api-accepts'),
+  endpointName = _.startCase(__dirname.split('/').pop()),
+  filename = _.startCase(__filename.split('/').pop().split('.')[0]),
+  sinon = require('sinon');
+
+describe(endpointName, function () {
+  describe(filename, function () {
+    let sandbox,
+      hostname = 'localhost.example.com',
+      acceptsJsonBody = apiAccepts.acceptsJsonBody(_.camelCase(filename)),
+      start = ['item1', 'item2'],
+      data = {
+        add: ['item3', 'item4'],
+        remove: ['item1']
+      },
+      end = ['item2', 'item3', 'item4'];
+
+    beforeEach(function () {
+      sandbox = sinon.sandbox.create();
+      return apiAccepts.beforeEachTest({ sandbox, hostname, pathsAndData: {'/_lists/valid': start} });
+    });
+
+    afterEach(function () {
+      sandbox.restore();
+    });
+
+    describe('/_lists/:name', function () {
+      const path = this.title;
+
+      // overrides existing data
+      acceptsJsonBody(path, {name: 'valid'}, data, 200, end);
+      acceptsJsonBody(path, {name: 'missing'}, data, 404);
+    });
+  });
+});