Example Coding Challenge

This application demonstrates one solution to the coding challenge below. The challenge is to write a javascript web application that takes user entry data and makes API calls showing the results.

This version uses:

• Svelte - A JavaScript library for building user interfaces.

It is considerably lighter than the equivalent NextJS/React version.

The solution is a single page web app (SPA).

Application

The application is compiled by svelte into the public/index.html file and a bundle.js file. The whole package is 15k. ( yes 15k!)

The main entry point is the App component. It is a Svelte component.

The page displays the EntryForm. When credentials are entered A GET request is made to the API to retrieve the user's data. The data are shown in the Repo Component. Data fetching is handled by plain browser fetch and does not take place until submit is clicked.

getRepoDetails is a function that takes the EntryForm values and sends a GET request to get the current Repo details. The data are then displayed in the Repo Component.

updateRepoURL is a function that takes the RepoForm url and calls the PATCH API to update the server record. It also calls the getRepoDetails function to revalidate the local data.

Components

Hero

<Hero title='Title' />

A simple header component that accepts a title prop.

Repo

<Repo repo={data} />

A display box for a GitHub repository. Titled with the user's email address and annotated with the created and modified dates of the record.

Forms

EntryForm

<EntryForm initialValues={creds} onChange={setCreds} />

The EntryForm shows a form with text inputs for the user to enter their email address, and secret and a button to submit the form, both fields are required. The form is validated - checking the email address format. On Submit the form data is stored in the parent creds state.

The parent calls the API with the credentials to retrieve the current settings record - including the id field. The result is shown using the Repo component. If the API call fails an error is shown and the user is offered a Registration button to create a new record.

RepoForm

<RepoForm url={data.repoURL} onSubmit={handleSubmit} />

The Repo form shows a single text input for the user to enter the URL of the repository. The form is validated - checking the URL format. On Submit the form data is stored in the parent data state and then the PATCH API is called to update the record.

Requirements

Your application must provide a GUI that allows a registered user to (without coding):

• Enter their email address and secret at the start of a session
• Modify their repository URL associated with their email address multiple times in the session.
• Confirm that their URL has been modified

You are welcome to use a tool like Postman to experiment with the API, but be aware that you need to finish working two hours after you register.

You may like to:

• Incorporate your name somewhere in the UI of the application
• Structure your code well and comment it where appropriate – we will look at it if your application seems to work.
• Let the user query the elapsed time since they registered and the date that the registration was last modified
• Query the repository URL currently registered for their email address
• Let the user register themselves initially through the application (it’s optional)
• Style the GUI in a way that is tasteful and clear and helpful to the user

Please do not:

• Get someone else to write the application for you – if you are interviewed we will ask you to talk us through your code and your design decisions.

API

1. To submit the URL of your code

PATCH to the URL https://tweakplan.com/JavaScriptDemoSubmission-1.0/candidates/:id (use the "id for subsequent calls" above in the URL)

Put the JSON {"repoURL":"{the URL of your git repository}","secret":"{your secret}"}

in the body of the request. repoURL: this is the URL of a public code repository containg your JavaScript client Example PATCH body {"repoURL":"https://github.com/goldleaf/alpha","secret":" Split the atom "}

You can call this endpoint as many times as you like.

It will return the updated details and update the “last modified” time each time.

2. To confirm that everything has registered as intended

GET https:///candidates?email=&secret=

You can call this as many times as you like.

It will return the updated details without changing the “last modified” time.

You can use it to retrieve your id number, or to check that you have succeeded in updating your repository URL.

svelte app

This is a project template for Svelte apps. It lives at https://github.com/sveltejs/template.

To create a new project based on this template using degit:

npx degit sveltejs/template svelte-app
cd svelte-app

Note that you will need to have Node.js installed.

Get started

Install the dependencies...

cd svelte-app
npm install

...then start Rollup:

npm run dev

Navigate to localhost:5000. You should see your app running. Edit a component file in src, save it, and reload the page to see your changes.

By default, the server will only respond to requests from localhost. To allow connections from other computers, edit the sirv commands in package.json to include the option --host 0.0.0.0.

If you're using Visual Studio Code we recommend installing the official extension Svelte for VS Code. If you are using other editors you may need to install a plugin in order to get syntax highlighting and intellisense.

Building and running in production mode

To create an optimised version of the app:

npm run build

You can run the newly built app with npm run start. This uses sirv, which is included in your package.json's dependencies so that the app will work when you deploy to platforms like Heroku.

Single-page app mode

By default, sirv will only respond to requests that match files in public. This is to maximise compatibility with static fileservers, allowing you to deploy your app anywhere.

If you're building a single-page app (SPA) with multiple routes, sirv needs to be able to respond to requests for any path. You can make it so by editing the "start" command in package.json:

"start": "sirv public --single"

Using TypeScript

This template comes with a script to set up a TypeScript development environment, you can run it immediately after cloning the template with:

node scripts/setupTypeScript.js

Or remove the script via:

rm scripts/setupTypeScript.js

If you want to use baseUrl or path aliases within your tsconfig, you need to set up @rollup/plugin-alias to tell Rollup to resolve the aliases. For more info, see this StackOverflow question.

Deploying to the web

With Vercel

Install vercel if you haven't already:

npm install -g vercel

Then, from within your project folder:

cd public
vercel deploy --name my-project

With surge

Install surge if you haven't already:

npm install -g surge

Then, from within your project folder:

npm run build
surge public my-project.surge.sh