feat(server): unsubscribe from topic

WIP, to be completed with API overhaul

src/server/handlers.js

@@ -81,10 +81,26 @@ const createHandlers = (adapter, storage, bot) => {
       return getTopics()
     },
 
+    removeTopic: async topic => {
+      const formerSubscribers = await storage.getSubscribers(topic)
+      const cancelSubscriptionTasks = formerSubscribers.map(user => {
+        return () => storage.cancelSubscription(user, topic)
+      })
+      await Promise.all(cancelSubscriptionTasks)
+      await storage.removeTopic(topic)
+      return getTopics()
+    },
+
     forceSubscription: async (user, topic) => {
       await storage.subscribe(user, topic)
       const subscribers = await storage.getSubscribers(topic)
       return subscribers
+    },
+
+    cancelSubscription: async (user, topic) => {
+      await storage.cancelSubscription(user, topic)
+      const currentSubscribers = await storage.getSubscribers(topic)
+      return currentSubscribers
     }
   }
 }

src/server/restify-server.js

@@ -17,7 +17,7 @@ const ensureTopic = req =>
 
 /**
  * restify server in charge of:
- *  - routing to handler functions
+ *  - routing to handler functions (delegating all business-logic)
  *  - logging requests and responses
  *  - extracting input from request (parsing)
  *  - handle HTTP status codes
@@ -31,7 +31,9 @@ const createRestifyServer = ({
   getUsers,
   getTopics,
   createTopic,
-  forceSubscription
+  removeTopic,
+  forceSubscription,
+  cancelSubscription
 }) => {
   const server = restify.createServer({ log })
   server.use(restify.plugins.queryParser())
@@ -54,41 +56,6 @@ const createRestifyServer = ({
     next()
   })
 
-  server.get('/api/v1/users', async (_, res, next) => {
-    const users = await getUsers()
-    res.send(200, users)
-    next()
-  })
-
-  server.get('/api/v1/topics', async (_, res, next) => {
-    const topics = await getTopics()
-    res.send(200, topics)
-    next()
-  })
-
-  server.post('/api/v1/topics', async (req, res, next) => {
-    const topic = req.body ? req.body.name : undefined
-    if (!topic) {
-      const err = new BadRequestError("required: 'name'")
-      return next(err)
-    }
-    const topics = await createTopic(topic)
-    res.send(200, topics)
-    next()
-  })
-
-  server.put('/api/v1/topics/:topic', async (req, res, next) => {
-    const user = req.body ? req.body.user : undefined
-    if (!user) {
-      const err = new BadRequestError("required: 'user'")
-      return next(err)
-    }
-    const topic = req.params.topic
-    const subscribers = await forceSubscription(user, topic)
-    res.send(200, { subscribers })
-    next()
-  })
-
   /** Resolves 202: Accepted */
   server.post('/api/v1/messages', async (req, res, next) => {
     await processMessage(req, res)
@@ -136,6 +103,69 @@ const createRestifyServer = ({
     }
   })
 
+  server.get('/api/v1/admin', (_, res, next) => {
+    const { routes } = server.getDebugInfo()
+    res.send(200, routes)
+  })
+
+  server.get('/api/v1/admin/users', async (_, res, next) => {
+    const users = await getUsers()
+    res.send(200, users)
+    next()
+  })
+
+  server.get('/api/v1/admin/topics', async (_, res, next) => {
+    const topics = await getTopics()
+    res.send(200, topics)
+    next()
+  })
+
+  server.post('/api/v1/admin/topics', async (req, res, next) => {
+    const topic = req.body ? req.body.name : undefined
+    if (!topic) {
+      const err = new BadRequestError("required: 'name'")
+      return next(err)
+    }
+    const topics = await createTopic(topic)
+    res.send(200, topics)
+    next()
+  })
+
+  server.del('/api/v1/topics/:topic', async (req, res, next) => {
+    const topic = req.body ? req.body.name : undefined
+    try {
+      const topics = await removeTopic(topic)
+      res.send(200, topics)
+      next()
+    } catch (err) {
+      next(err)
+    }
+  })
+
+  server.put('/api/v1/topics/:topic/subscribers', async (req, res, next) => {
+    const user = req.body ? req.body.user : undefined
+    if (!user) {
+      const err = new BadRequestError("required: 'user'")
+      return next(err)
+    }
+    const topic = req.params.topic
+    const subscribers = await forceSubscription(user, topic)
+    res.send(200, { subscribers })
+    next()
+  })
+
+  // server.del('/api/v1/topics/:topic', async (req, res, next) => {
+  //   const user = req.body ? req.body.user : undefined
+  //   if (!user) {
+  //     const err = new BadRequestError("required: 'user'")
+  //     return next(err)
+  //   }
+  //   const topic = req.params.topic
+  //   const subscribers = await cancelSubscription(user, topic)
+  //   res.send(200, { subscribers })
+  //   next()
+  // })
+
   return {
     /**
      * @param {object=} param0

src/server/restify-server.test.js

@@ -20,9 +20,14 @@ const mockedHandlers = {
     orange: ['[email protected]', '[email protected]'],
     tangerine: []
   }),
+  removeTopic: jest.fn().mockResolvedValue({
+    banana: ['[email protected]'],
+    tangerine: []
+  }),
   forceSubscription: jest
     .fn()
-    .mockResolvedValue(['[email protected]', '[email protected]'])
+    .mockResolvedValue(['[email protected]', '[email protected]']),
+  cancelSubscription: jest.fn().mockResolvedValue(['[email protected]'])
 }
 
 describe('createRestifyServer()', () => {
@@ -107,6 +112,21 @@ describe('createRestifyServer()', () => {
     })
   })
 
+  describe('[DELETE] /api/v1/topics', () => {
+    it('[200] routes to removeTopic()', done => {
+      // @ts-ignore
+      client.del('/api/v1/topics', (_, __, res, data) => {
+        expect(res.statusCode).toEqual(200)
+        expect(data).toEqual({
+          banana: ['[email protected]'],
+          tangerine: []
+        })
+        expect(mockedHandlers.removeTopic).toHaveBeenCalledWith('')
+        done()
+      })
+    })
+  })
+
   describe('[PUT] /api/v1/topics/{topic}', () => {
     it("[400] requires 'user'", done => {
       client.put(
@@ -255,7 +275,11 @@ describe('createRestifyServer()', () => {
     it('[202] routes to broadcast() (considering topic creation)', done => {
       client.post(
         '/api/v1/broadcast',
-        { topic: 'orange', message: 'orange event', createTopicIfNotExists: true },
+        {
+          topic: 'orange',
+          message: 'orange event',
+          createTopicIfNotExists: true
+        },
         // @ts-ignore
         (_, __, res, data) => {
           expect(mockedHandlers.broadcast).toHaveBeenCalledWith(

src/storage/mysql.js

@@ -99,9 +99,30 @@ const ensureTopic = async topic => {
 const registerTopic = async topic =>
   ensureTopic(topic).then(instance => !!instance)
 
+/**
+ * @param {string} topic
+ * @return {Promise<boolean>}
+ */
+const removeTopic = async topic => {
+  log.debug(`[db] removing topic: "${topic}"`)
+  return Topics.destroy({ where: { name: topic } })
+    .then(affectedRows => {
+      if (affectedRows === 1) {
+        log.debug(`[db] removed topic "${topic}"`)
+        return true
+      }
+      log.warn(`[db] unexpected affected rows removing topic "${topic}"`)
+      return false
+    })
+    .catch(err => {
+      log.error(`[db] unable to remove topic "${topic}"`, err)
+      return false
+    })
+}
+
 /**
  * @param {string} user
- * @return {Promise<{userInstance: any, topics: string[]|null}>}
+ * @return {Promise<{userInstance: any, topics: string[]}|null>}
  */
 const getAllUserInfo = async user => {
   log.debug(`[db] reading subscriptions for user "${user}"`)
@@ -157,6 +178,15 @@ const subscribe = async (user, topic) => {
     })
 }
 
+/**
+ * @param {string} user
+ * @param {string} topic
+ * @return {Promise<boolean>}
+ */
+const cancelSubscription = async (user, topic) => {
+
+}
+
 /**
  * @param {string} topic
  * @return {Promise<string[]|null>}
@@ -268,7 +298,9 @@ const storage = {
   saveConversation,
   getConversation,
   registerTopic,
+  removeTopic,
   subscribe,
+  cancelSubscription,
   getSubscribedTopics,
   getSubscribers,
   listUsers,

types.d.ts

@@ -22,9 +22,13 @@ declare namespace Types {
     /** @return success flag (independently of actual operation - e.g. already existing entry) */
     registerTopic: (topic: string) => Promise<boolean>;
 
+    removeTopic: (topic: string) => Promise<boolean>;
+
     /** @return success flag (independently of actual operation - e.g. already existing entry) */
     subscribe: (user: string, topic: string) => Promise<boolean>;
 
+    cancelSubscription: (user: string, topic: string) => Promise<boolean>;
+
     /** @return null if err */
     getSubscribedTopics: (user: string) => Promise<string[] | null>;
 
@@ -50,6 +54,8 @@ declare namespace Types {
     ensureTopic?: boolean;
   }
 
+  type TopicsDictionary = { [topic: string]: string[] };
+
   interface Handlers {
     /* bot-SDK entry point */
     processMessage: (
@@ -76,14 +82,18 @@ declare namespace Types {
     /* debugging */
 
     getUsers: () => Promise<string[]>;
-    getTopics: () => Promise<{ [topic: string]: string[] }>;
+    getTopics: () => Promise<TopicsDictionary>;
 
     /* ops */
 
     /** @return topics */
-    createTopic: (topic: string) => Promise<{ [topic: string]: string[] }>;
+    createTopic: (topic: string) => Promise<TopicsDictionary>;
+    /** @return topics */
+    removeTopic: (topic: string) => Promise<TopicsDictionary>;
     /** @return subscribers */
     forceSubscription: (user: string, topic: string) => Promise<string[]>;
+    /** @return subscribers */
+    cancelSubscription: (user: string, topic: string) => Promise<string[]>;
   }
 
   interface ICard {