Cyber4 segz

01-making-promises/answers.js

@@ -5,8 +5,11 @@
  * 
  * @returns {Promise<3>}
  */
-function makePromiseResolveWith3(){
-  /* IMPLEMENT ME! */
+function makePromiseResolveWith3() {
+  return new Promise((resolve) => {
+    resolve(3);
+
+  });
 }
 
 /**
@@ -15,8 +18,11 @@ function makePromiseResolveWith3(){
  * 
  * @returns {Promise<,"Boo!">}
  */
-function makePromiseRejectWithBoo(){
-  /* IMPLEMENT ME! */
+function makePromiseRejectWithBoo() {
+  return new Promise((resolve, reject) => {
+    reject('Boo!');
+
+  });
 }
 
 /**
@@ -27,10 +33,13 @@ function makePromiseRejectWithBoo(){
  * @returns {Promise<undefined, undefined>}
  */
 
-function makePromiseWithConstructor(itShouldResolve){
+function makePromiseWithConstructor(itShouldResolve) {
   return new Promise((resolve, reject) => {
-    /* If itShouldResolve is true, call resolve */
-    /* If itShouldResolve is false, call reject */
+    if (itShouldResolve == true) {
+      resolve('truthy');
+    } else {
+      reject('falsy');
+    }
   });
 }
 
@@ -42,8 +51,12 @@ function makePromiseWithConstructor(itShouldResolve){
  * @param {number} delayInMs 
  * @return {Promise<any>} - A promise that will resolve with the value after delayInMs milliseconds
  */
-function makeDelayPromise(value, delayInMs){
-  /* Return a promise that resolves with the value after delayInMs */
+function makeDelayPromise(value, delayInMs) {
+  return new Promise((resolve) => {
+    setTimeout(() => {
+      resolve(value);
+    }, delayInMs);
+  });
 }
 
 module.exports = {

01-making-promises/test.js

@@ -39,10 +39,10 @@ describe('Promise constructor "new Promise((resolve, reject) => void) => Promise
       return makePromiseWithConstructor(false)
         .then(() => {
           assert.fail('This should have failed.');
-        }, () => {});
+        }, () => { });
     });
   });
-  describe('#makeDelayPromise: (A, number) => Promise<A>', () =>{
+  describe('#makeDelayPromise: (A, number) => Promise<A>', () => {
     it('returns a promise that resolves with the value', () => {
       const start = new Date();
       return makeDelayPromise('Hello', 0)

02-consuming-promises/answers.js

@@ -6,8 +6,10 @@
  * @param {thunk} action
  * 
  */
-function waitForPromise(promise, action){
-  /* IMPLEMENT ME */
+function waitForPromise(promise, action) {
+  return promise.then(() => {
+    action();
+  });
 }
 /**
  * 
@@ -17,8 +19,12 @@ function waitForPromise(promise, action){
  * @param {consumer} consumer 
  * @param {handler} handler 
  */
-function consumePromise(promise, consumer, handler){
-  /* IMPLEMENT ME! */
+function consumePromise(promise, consumer, handler) {
+  promise.then((value) => {
+    return consumer(value);
+  }).catch((error) => {
+    return handler(error);
+  });
 }
 
 /**

03-transforming-promises/answers.js

@@ -6,9 +6,13 @@
  * @param {*} transformer 
  * @returns {Promise}
  */
-function mapPromise(promise, transformer){
+function mapPromise(promise, transformer) {
   return new Promise((resolve, reject) => {
-    /* IMPLEMENT ME!! */
+    promise
+      .then(value => transformer(value))
+      .then(value => resolve(value))
+      .catch(error => reject(error))
+      .catch(error => reject(error));
   });
 }
 
@@ -19,9 +23,19 @@ function mapPromise(promise, transformer){
  * @param {Promise<number | string>} numberPromise 
  * @returns {Promise<number>}
  */
-function squarePromise(numberPromise){
+function squarePromise(numberPromise) {
   return numberPromise
-    .then(/* IMPLEMENT ME! */);
+    .then(response => {
+      return new Promise((resolve, reject) => {
+        if (!isNaN(response)) {
+          resolve(response * response);
+        } else {
+          reject(`Cannot convert '${response}' to a number!`);
+        }
+
+      });
+
+    });
 }
 
 /**
@@ -30,9 +44,13 @@ function squarePromise(numberPromise){
  * @param {Promise<number | string>} numberPromise 
  * @returns {Promise<number>}
  */
-function squarePromiseOrZero(promise){
+function squarePromiseOrZero(promise) {
   return squarePromise(promise)
-    .catch(/* IMPLEMENT ME! */);
+    .catch(() => {
+      return new Promise((resolve) => {
+        resolve(0);
+      });
+    });
 }
 
 /**
@@ -41,8 +59,8 @@ function squarePromiseOrZero(promise){
  * @param {Promise} promise 
  * @returns {Promise}
  */
-function switcheroo(promise){
-  return promise.then(/* IMPLEMENT ME */);
+function switcheroo(promise) {
+  return promise.then(res => Promise.reject(res), res2 => Promise.resolve(res2));
 }
 
 /**

04-chaining-promises/answers.js

@@ -5,10 +5,16 @@
  * @param {Promise} promise 
  * @param {function} asyncTransformer 
  */
-function flatMapPromise(promise, asyncTransformer){
+function flatMapPromise(promise, asyncTransformer) {
   return new Promise((resolve, reject) => {
     promise
-      .then(/* IMPLEMENT ME! */);
+      .then(response => {
+        resolve(asyncTransformer(response));
+
+      })
+      .catch((error) => {
+        reject(error);
+      });
   });
 }
 
@@ -19,8 +25,10 @@ function flatMapPromise(promise, asyncTransformer){
  * @param {Promise} firstPromise 
  * @param {function} slowAsyncProcess 
  */
-function chainTwoAsyncProcesses(firstPromise, slowAsyncProcess){
-  return firstPromise.then(/* IMPLEMENT ME! */);
+function chainTwoAsyncProcesses(firstPromise, slowAsyncProcess) {
+  return firstPromise.then(response => {
+    return (slowAsyncProcess(response));
+  });
 }
 
 /**
@@ -30,9 +38,16 @@ function chainTwoAsyncProcesses(firstPromise, slowAsyncProcess){
  * @param {function} getUserById 
  * @param {function} getOrganizationById 
  */
-function makeGetUserByIdWithOrganization(getUserById, getOrganizationById){
-  return function getUserByIdWithOrganization(userId){
-    /* IMPLEMENT ME! */
+function makeGetUserByIdWithOrganization(getUserById, getOrganizationById) {
+  return function getUserByIdWithOrganization(userId) {
+    return getUserById(userId).then(userobj => {
+      if (userobj) {
+        return getOrganizationById(userobj.organizationId).then(orgobj => {
+          userobj.organization = orgobj;
+          return userobj;
+        });
+      }
+    });
   };
 }
 

05-callbacks/answers.js

@@ -3,9 +3,9 @@
  * @param {string} password 
  * @returns {User | undefined}
  */
-function passwordChecker(email, password){
-  if(email === '[email protected]' && password === 'jeff'){
-    return {name: 'Jeff Jeffries', email: '[email protected]'};
+function passwordChecker(email, password) {
+  if (email === '[email protected]' && password === 'jeff') {
+    return { name: 'Jeff Jeffries', email: '[email protected]' };
   }
   return undefined;
 }
@@ -15,9 +15,9 @@ function passwordChecker(email, password){
  * @param {string} password 
  * @param {nodeStyleCallback} cb 
  */
-function passwordCheckerCb(email, password, cb){
+function passwordCheckerCb(email, password, cb) {
   const user = passwordChecker(email, password);
-  if(user){
+  if (user) {
     cb(null, user);
   } else {
     setTimeout(() => {
@@ -34,10 +34,12 @@ function passwordCheckerCb(email, password, cb){
  * @param {string} password 
  * @returns {Promise<User, string>}
  */
-function passwordCheckerPrms(email, password){
+function passwordCheckerPrms(email, password) {
   return new Promise((resolve, reject) => {
     passwordCheckerCb(email, password, (error, user) => {
-      /* IMPLEMENT ME! */
+      if (!error) {
+        resolve(user);
+      } else { reject(error); }
     });
   });
 }
@@ -50,7 +52,14 @@ function passwordCheckerPrms(email, password){
  * @param {*} fnParams 
  * @return {Promise<any, any>}
  */
-function makePromiseFromFunctionWithCallback(fn, ...fnParams){
+function makePromiseFromFunctionWithCallback(fn, ...fnParams) {
+  return new Promise((resolve, reject) => {
+    fn(...fnParams, (error, user) => {
+      if (!error) {
+        resolve(user);
+      } else { reject(error); }
+    });
+  });
   /* 
   Return a promise that 
     - calls fn with the fnParams and a callback (like fn(...fnParams, cb))