First Express Homework
Practice the Basics of Express
Learning Objectives
- Set up some express servers for practice
- make some get routes
- use url/query parameters
Prerequisites
- Nodejs
- npm packages
- Introduction to expressjs
- Request/response/ how the internet works basics
- Basic understanding of routing
- JavaScript, HTML fundamentals
Technical Requirements
- Must be able run without syntax errors (ok if it breaks after the user tries to do something, though do try to comment on the code that isn't working)
- Must get functionality required for each section working
Learning Objectives
- Practice setting up express applications.
- Practice creating custom routes.
- Practice using parameters from a request.
Getting Started
In your homework directory for today, create a Javascript file server.js. Write your answers inside this one js file.
npm init -y. You should receive apackage.json.
Install express. npm i express. Check your files.
:elephant: Hint: You can check to make sure your installation was successful in one of the following places:
- Your
package.jsonfile should haveexpresslisted in the dependencies. - You could also check in your
node_modulesfolder to see anexpressfolder. - Require
expressand set theapp. (look back to the markdown from today if you need more help on how to do this). - Tell the server where to listen for requests (the port).
Greetings
- Make a route
'/greeting'that sends a generic greeting to the screen like "Hello, stranger". - Give the
greetingroute a param/:name - When hitting the route, the page should display a message such as "Hello,
", or "What's up, <name>", or "<name>! It's so great to see you!" (ex. hitting'/greeting/Jimmy-boy'should displayWow! Hello there, Jimmy-boyon the page).
🔴 Commit
"Greeting express application created."
Tip Calculator
- Your app should have a route of
'/tip'and it should expect 2 params. One should betotaland one should betipPercentage. - When hitting the route, the page should display how much your tip will be based on the total amount of the bill and the tip percentage. (ex. hitting
'/tip/100/20'should display20on the page).
🔴 Commit
"Tip Calculator express application created."
Magic 8 Ball
- Create a route of
'/magic'that should expect a phrase in the URL that ask the Magic 8 ball a question. - So if the user hits that route and asks a question of "Will I be a Millionaire" (ex.
'/magic/Will%20I%20Be%20A%20Millionaire') he should have return to him his question AND a random Magic 8 ball response (see the array below) on the screen. - We can't use spaces in the url, so we use
%20to express a space in the url. - So if the user hits that route and asks a question of "Will I be a Millionaire" he should get his question asked and a random Magic 8 ball quote on the screen.
- Send the magic 8 ball response back between html
<h1>tags - Use this array of Magic 8 ball responses.....
["It is certain", "It is decidedly so", "Without a doubt", "Yes definitely","You may rely on it", "As I see it yes", "Most likely", "Outlook good","Yes", "Signs point to yes", "Reply hazy try again", "Ask again later","Better not tell you now", "Cannot predict now", "Concentrate and ask again","Don't count on it", "My reply is no", "My sources say no","Outlook not so good", "Very doubtful"]🔴 Commit
"Magic 8 Ball express application created."
Hungry for more?
Fibonacci
Back in your main app:
- Add
Fibonnacias a comment in your application. - Create a route 'fibonacci'
- This route will take one param, the number we will operate on.
- If the number param is not a fibonacci number, print out "I can tell this is not a fibonacci number."
- If the number is a Fibonacci number print out "Very good. It is Fibonacci."
🔴 Commit
"Fibonacci."
HackerRank
Sign up for HackerRank. Solve a few of the problems (this will help get you prepared for interviews! A lot of companies use this site for pre-screening interviews.). Some companies use hackarrank as part of an interview process, so getting familiar with the interface can be a good move