使用JavaScript完成网页开发

Getting Started – gitlab.cse.unsw.edu.au
You must store all work on the assignment as you complete it in a repository at gitlab.cse.unsw.edu.au.
Don’t panic this is easy to do and will ensure you have a complete backup of all work on your assignment and can return to its state at any stage.
And hopefully assignment 1 has left you familiar for git.
It will also allow your tutor to check you are progressing on the assignment as they can access your gitlab repository You need to add your CSE ssh key to your gitlab.cse.unsw.edu.au account. Here is how you do that:
1. First print your CSE ssh key. If you have one, this command should should work.
$ cat ~/.ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAyNSzIDylSPAAGLzUXdw359UhO+tlN6wWpr SBc9gu6t3IQ1rvHhPoD6wcRXnonY6ytb00GpS4XRFuhCghx2JNVkXFykJYt3XNr1xkPItM mXr/DRIYrtxTs5sn9el3hHZIgELY8jJZpgIo303kgnF0MsB7XpqCzg7Iv6JGkv7aEoYC/M Nr07hXE8iQjYIHDMdO9HxGI80GyMqb1hF+RSpQTNvXQvH56juu9VXt5OwJjOqSVa4SfsEI Cqdn+3k9w8Z4EaD93Eeog3hz0RoTrme8h/sJenXydJ0w9ZOs0By4fjqKFYPsYEs1K6SHma +kPByZM9COgKHZwOZHH1m24HOITQ== [email protected]
2. If you couldn’t print an ssh key with the above command, you need to generate a new ssh key. You can do it like this (just hit return for each question).
$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/import/kamen/3/z5555555/.ssh/id_ rsa):
Created directory ‘/import/kamen/3/z5555555/.ssh’.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /import/kamen/3/z5555555/.ssh/id _rsa.
Your public key has been saved in /import/kamen/3/z5555555/.ssh/id_rs a.pub.
The key fingerprint is: b8:02:31:8b:bf:f5:56:fa:b0:1c:36:89:ad:e1:cb:ad [email protected]
The key’s randomart image is:
…
3. Now add your ssh key to gitlab:
4. Go to https://gitlab.cse.unsw.edu.au/profile/keys/
5. In the field labelled UNSW Username enter your zid (e.g. z5555555)
6. In the field labelled Password enter your zpass
Sign in
8. Cut-and-paste your ssh-key (the entire 200+ character line printed by cat ~/.ssh/id_rsa.pub) into the “Key” field. Don’t cut-and paste z5555555’s ssh key above – cut-and-paste your ssh-key!
9. At this point, your screen should look something like this:10. click the green Add key button
A repository has been created for your assignment on gitlab.cse.unsw.edu.au. You need to add your CSE ssh key to your gitlab.cse.unsw.edu.au.
After you have done that create a git repository for the assignment in your CSE account. These commands will create a copy of the gitlab repository in your CSE account.
Make sure you replace 5555555 below by your student number!
Getting Started – Cloning the Assignment Repo
You should first clone your gitlab.cse.unsw.edu.au repository for this assignment
$ git clone [email protected]:z5555555/19T2-comp2041-ass2 . Cloning into ‘.’…
….
If the git clone above fails – redo the instructions above for adding your ssh key to gitlab.
And if that fail try with a https url instead (again replacing 5555555 with your zid) – and supplying your zid/zpass when requested:
Username for ‘https://gitlab.cse.unsw.edu.au’:
Password for ‘https://[email protected]’:
Updating The Supplied Files
Run this command to make sure you have the latest version of the supplied files:
$ git pull starting_files
Pushing Your work to gitlab.cse.unsw.edu.au
Every time you complete some work on the assignment you should commit to your git rep and push this to gitlab, for example:Seddit – Introduction
JavaScript is used increasingly to provide a native-like application experience in the web. One major avenue of this has been in

the use of Single Page Applications or SPAs. SPAs are generated, rendered, and updated using JavaScript. Because SPAs don’t require a user to navigate away from a page to do anything, they retain a degree of user and application state.
There are millions of websites that utilise SPAs in part of, or all of their web applications.
The assignment intends to teach students to build a simple SPA which can fetch dynamic data from a HTTP/S API. Your task will be to provide an implemention of a SPA that can provide a number of key features.
Some of the skills/concepts this assignment aims to test (and build upon):
Simple event handling (buttons) Advanced Mouse Events (Swipe) Fetching data from an API Infinite scroll
CSS Animations
Web Workers
Push Notifications (Polling)
Offline Support
Routing (URL fragment based routing)
API
The backend server will be where you’ll be getting your data. Don’t touch the code in the backend; although we’ve provided the source, it’s meant to be a black box. Final testing will be done with our own backend so don’t assume any single piece of data will be there. Use the instructions provided in the backend/README.md to get it started.
For the full docs on the API, start the backend server and navigate to the root (very likely to be localhost:5000, the exact url will be printed when you run the backend, see backend/README.md for more info). You’ll see all the endpoints, descriptions and expected responses.
A Working Product
Your application should be compatible with ‘modern’ Chrome, Safari, and Mozilla browsers. We will assume your browser has JavaScript enabled, and supports ES6 syntax.
Writing HTML – Restrictions
You are not permitted to edit the HTML provided in frontend/index.html except you may change the <head></head> section to add your own styles and scripts.
You are not permitted to add HTML files.
You must create the HTML entirely via your JavaScript scripts. Your task is to manipulate and control your application entirely dynamically!
Also please use .innerHTML sparingly. Using .innerHTML amounts to the same thing as hardcoding your HTML. You’ll be penalised if you rely on this method. Ask in the forum if you require more information.
You are not permitted to use Javascript written by other people.
You are not permitted to use NPM to install packages.
You are not permitted to use frameworks (React, Angular, Vue …)
You are permitted to use small snippets of general purpose code from external sources such as Stack Overflow with proper attribution.
Getting StartedClone the repository provided. It has a whole bunch of code, documentation, and a whole working server you’ll need for developing your frontend applicaiton.
Please read the relevant docs for setup in the folders /backend and /frontend of the provided repository. Each folder outlines basic steps to get started. There are also some comments provided in the frontend source code.
Milestones
Level 0 focuses on the basic user interface and interaction with of the site. There is no need to implement any integration with the backend for this level. When demonstrating the functionality included in level 0, you are not required to prevent access to login- protected pages – all pages may be accessible by changing the URL.
Level 0
Login
The site presents a login form where a user can present their credentials. Since we do not need to interact with the backend for level 0, all attempts to log in would fail. Thus, you should allow the site to inform the user that authentication has failed.
Registration
An option to register for “Seddit” should be presented on the home page. This option will allow the user to create an account by entering a set of credentials (username and password) which they can then use to sign up to “Seddit”. Again, since we are not required to interact with the backend for level 0, all attempts to create a new account will fail. You must perform basic input validation (think about the format of the user input you may receive) and handle cases where the input credentials should be rejected in the case of user error or (eventual) server rejection due to conflicting credential details.
Feed Interface
The application should present a “feed” of user content on the home page derived from the sample feed.json provided. The posts should be displayed in reverse chronological order (most recent posts first). You can hardcode how this works for this milestone.
Although this is not a graphic design exercise you should produce pages with a common and somewhat distinctive look-and-feel. You may find CSS useful for this.
Each post must include: 1. who the post was made by (must include data-id-author) 2. when it was posted 3. The image itself, if there is one present 4. How many upvotes it has (or none) (must include data-id-upvotes) 5. The post title (must include data- id-title) 6. The post description text 7. How many comments the post has 8. What suseddit this was posted to i,e /s/meme
While completing these tasks for level 0, consider the future inclusion of HTTP requests when designing your code – this will be helpful for future levels.
Level 1
Level 1 focuses on fetching data from the API.Assignment 2 – Seddit
Login The login form now communicates with the backend (POST /login) after input validation to verify whether the provided credentials are valid for an existing user. Once the user has logged in, they should see their own news feed (the home page).
NB. This is slightly different to what they will see as a non-logged in user. A non-logged in user should still see posts from GET /post/public.
Registration The option to register for “Seddit” (implemented in level 0) should now accept a set of credentials (a username / password pair). This user information is then POSTed to the backend to create the user in the database (POST /signup).
Feed Interface The content shown in the user’s feed is sourced from the backend (GET /user/feed). Contrary to the existing popular system which “Seddit” is based off, there is only one location where all posts are to appear at this level of functionality. In the actual system called reddit posts are organised into similar groups called “sub-reddits” so all posts about plants are grouped under r/plants allowing plant lovers to only see those posts. seddit copies this by letting users specify the subseddit of a post when creating
it so people can make posts under s/plants but the feed we are asking you to implement aggregates all posts regardless of which subseddit they were posted to.
In level 4 you will implement multiple subseddits where posts are organised into groups much like reddit.
Level 2
Level 2 focuses on a richer UX and will require some further backend interaction.
Show Upvotes Allow an option for a user to see a list of all users who have upvoted a post. Possibly a modal but the design is up to you.
Show Comments Allow an option for a user to see all the comments on a post. Same as above.
Upvote user generated content A logged in user can upvote a post on their feed and trigger a api request (PUT /post/vote) For
now it’s ok if the upvote doesn’t show up until the page is refreshed.
Post new content Users can upload and post new content from a modal or seperate page via (POST /post). The uploaded content can either be text, an image, or a combination of both.
Pagination Users can page between sets of results in the feed using the position token with (GET /user/feed). Note users can ignore this if they properly implement Level 3’s Infinite Scroll.
Profile Users can see their own profile information such as username, number of posts, number of upvotes across all posts, profile pic. Get this information from (GET /user)
Level 3
Level 3 focuses on more advanced features that will take time to implement and will involve a more rigourously designed app to execute.
Infinite Scroll Instead of pagination, users an infinitely scroll through the “subseddit” they are viewing. For infinite scroll to be properly implemented you need to progressively load posts as you scroll.
Comments Users can write comments on “posts” via (POST /post/comment)
Live Update If a user upvotes a post or comments on a post, the posts upvotes and comments should update without requiring a page
reload/refresh.
Update Profile Users can update their personal profile via (PUT /user) E.g: * Update email address * Update their profile picture * Update password
User Pages Let a user click on a user’s name/picture from a post and see a page with the users name, profile pic, and other info. The user should also see on this page all posts made by that person across all “subseddits”. The user should be able to see their own page as well.
This can be done as a modal or as a separate page (url fragmentation can be implemented if wished.)
Follow Let a user follow/unfollow another user too add/remove their posts to their feed via (PUT user/follow) Add a list of everyone
a user follows in their profile page. Add just the count of followers / follows to everyones public user page Delete/Update Post Let a user update a post they made or delete it via (DELETE /post) or (PUT /post)
Search functionality Let a user search for a post, user or subseddit. You’ll have to potentially combine a few different endpoint responses to allow this.
Level 4
This set of tasks is an extension beyond the previous levels and should only be attempted once the previous levels have been completed.