new paginated functionality added in GET /tasks

controllers/tasks.js

@@ -35,8 +35,10 @@ const addNewTask = async (req, res) => {
  * @param res {Object} - Express response object
  */
 const fetchTasks = async (req, res) => {
+  const { limit, offset } = req.query;
+
   try {
-    const allTasks = await tasks.fetchTasks();
+    const allTasks = await tasks.fetchTasks(limit, offset);
     return res.json({
       message: "Tasks returned successfully!",
       tasks: allTasks.length > 0 ? allTasks : [],

models/tasks.js

@@ -44,9 +44,17 @@ const updateTask = async (taskData, taskId = null) => {
  *
  * @return {Promise<tasks|Array>}
  */
-const fetchTasks = async () => {
+const fetchTasks = async (limit, offset) => {
+  let lastDoc;
+  if (offset) {
+    lastDoc = await tasksModel.doc(offset).get();
+    lastDoc = lastDoc.data();
+  }
+  const limitDocuments = Number(limit);
+
   try {
-    const tasksSnapshot = await tasksModel.get();
+    const tasksSnapshotQuery = tasksModel.orderBy("startedOn", "desc").startAfter(lastDoc ? lastDoc.startedOn : "");
+    const tasksSnapshot = limit ? await tasksSnapshotQuery.limit(limitDocuments).get() : await tasksSnapshotQuery.get();
     const tasks = buildTasks(tasksSnapshot);
     const promises = tasks.map(async (task) => fromFirestoreData(task));
     const updatedTasks = await Promise.all(promises);

test/integration/tasks.test.js

@@ -135,6 +135,57 @@ describe("Tasks", function () {
             expect(taskWithParticipants.assignee).to.equal(appOwner.username);
           }
 
+          return done();
+        });
+    });
+    it("Should get all the list of tasks by paginated", function (done) {
+      const limit = 1;
+      const chaiRequester = chai.request(app).keepOpen();
+      chaiRequester
+        .get("/tasks")
+        .query({ limit })
+        .end((err, res) => {
+          if (err) {
+            return done(err);
+          }
+
+          expect(res).to.have.status(200);
+          expect(res.body).to.be.a("object");
+          expect(res.body.tasks).to.be.a("array");
+          const offset = { ...res.body.tasks[0] };
+
+          chaiRequester
+            .get("/tasks")
+            .query({ offset: offset.id })
+            .end((err, res) => {
+              if (err) {
+                return done(err);
+              }
+              expect(res).to.have.status(200);
+              expect(res.body.tasks).to.be.a("array");
+              const taskWithParticipants = res.body.tasks;
+              expect(taskWithParticipants[0]).not.to.equal(offset);
+              return chaiRequester.close();
+            });
+          return done();
+        });
+    });
+    it("Should get all the list of tasks limited in number by the 'limit' passed in query", function (done) {
+      const limit = 1;
+      const chaiRequester = chai.request(app);
+      chaiRequester
+        .get("/tasks")
+        .query({ limit })
+        .end((err, res) => {
+          if (err) {
+            return done(err);
+          }
+
+          expect(res).to.have.status(200);
+          expect(res.body).to.be.a("object");
+          expect(res.body.tasks).to.be.a("array");
+          expect(res.body.tasks.length).to.equal(limit);
+
           return done();
         });
     });