A progressive search experience in Next

In this article I will explore the idea of a progressively enhanced approach for a search experience, using the browser's native behavior first, giving control back to JavaScript only when needed.

We will see how using the web platform as a base is a great option to write less code on the client while providing a good experience for users, even without JavaScript enabled.

# A world with no JavaScript

It sounds horrifying, isn't it? But don't worry, JavaScript is going nowhere.

And it shouldn't, it’s one of the reasons why building on the web is great today, but it's not the only tool we have available and it's usually a pretty critical one.

Nevertheless, we keep building sites and implementing new features with the thought that JavaScript will always be there. I remember talking about this with Harry Roberts and he said:

I’m willing to bet you have more IE6 visitors than disabled-JavaScript-on-purpose visitors. Your IE6 policy is probably ‘forget it’, so why would your disabled-JavaScript-on-purpose policy be any different?

Harry Roberts

There are a lot of chances this is true for most of the projects out there, and it makes you question why we should even bother to support a JavaScript-disabled scenario. Later, he closes his quote with this:

All your users are non-JavaScript while they are downloading your JavaScript’. So while I don’t think we should build or optimize for visitors who have disabled JavaScript, we shouldn’t make too many assumptions that our JavaScript will always work as we expect.

Jake Archibald

We do rely more and more on client code, and it's a trend that seems to not stop soon. It gave me a lot of thinking as someone who started coding when frameworks weren't a big thing.

What if we lean back on the platform while still using them only to fill the gaps and improve things? Will that strategy translate into less and even better code or will this negatively impact the user experience?

# Back to the progressive mindset

When I became a web developer, there were two terms which got repeated pretty often, like mantras to have present every time you were building something.

One was graceful degradation, a concept in computing and electronic systems where they are still useful or functional even if some parts are not working correctly or have been removed.

The second one was progressive enhancement, a strategy of prioritizing web content delivery first and start adding improvements to the experience as the user could afford them or as they were supported.

Keeping these two concepts close, let's dive into a search application with form submission, data fetching, paged results, and URL persistence.

To start, let's disable JavaScript in the browser.

# Form submission and accessibility

As a first building block, I'm choosing Next, a framework built on top of React. Since I won't have JavaScript available on the client I need a stack that gives me control on the server-side.

On the index page, we start with the basic set of elements to get input from the user and fetch data later. If we forget about our premise in this article and assume JavaScript is there, we only need an input element and a button.

import React, { useState } from 'react';

const Index = () => {
  const [search, setSearch] = useState('');

  function onSubmit(search) {}

  return (
    <>
      <input value={search} onChange={(evt) => setSearch(evt.target.value)} />
      <button onClick={() => onSubmit(search)}>Search</button>
    </>
  );
};

export default Index;

Is the name attribute in our input necessary? Do we need to wrap everything in a form? What about setting the action on the form? The short answer is, to fetch data with JavaScript, you don't need any of those.

But in the same way you have to write back all the native functionality of a button element when using a div, writing a semantically correct form will save you from a lot of heavy lifting while enabling a better and more accessible experience at the same time.

import React, { useState } from 'react';

function onSubmit() {}

const Index = () => {
  const [search, setSearch] = useState('');

  return (
    <form action="?" onSubmit={onSubmit}>
      <input
        name="search"
        value={search}
        onChange={(evt) => setSearch(evt.target.value)}
      />
      <button type="submit">Search</button>
    </form>
  );
};

export default Index;

See this example in action

A button alone does nothing without JavaScript, like in the first code example.

In the second one, things are different. Users can submit by clicking, and even by using a keyboard. More importantly, we moved from an inert application to one that does something, all without a single line of code on the client.

Right now our application does one thing, after the user submits the page refreshes but now with the search value appended to the URL, which gives us back the control on the server-side.

We can see now the importance of the name and action attributes.

# Fetching data on the server side

After a search submission, a page request hits the server. There we can inspect the new parameters in the URL to know what data to fetch.

For this, we are going to use a method called getInitialProps provided by Next, really convenient as it runs on each page request but also on route changes, useful to enhance the experience for users with JavaScript.

Index.getInitialProps = async ({ query }) => {
  const currentSearch = query.search;
};

getInitialProps receives a context argument, this object holds a collection of properties including the query section of the URL, which here contains the information from the form submitted by the user.

We use the search value of the query to request data from another service and return an object with the result, Next passes this object to the page component as props.

As an example, we use the Open Movie Database API service.

import unfetch from 'isomorphic-unfetch';

Index.getInitialProps = async ({ query }) => {
  const currentSearch = query.search;

  if (!currentSearch) return {};

  const searchUrl = `//www.omdbapi.com/?s=${currentSearch}`;
  const response = await unfetch(searchUrl);
  const results = await response.json();

  return {
    currentSearch,
    pageResults: results.Search
  };
};

An undefined search value indicates we aren’t coming from a form submission, so we return an empty object.

Inside our Index page component we inspect the value of the current search passed by the getInitialProps method and iterate over the data to show the results.

import React, { useState } from 'react';
import Link from 'next/link';

function onSubmit() {}

const Index = (props) => {
  const { pageResults, currentSearch } = props;
  const [search, setSearch] = useState('');

  return (
    <>
      <form action="?" onSubmit={onSubmit}>
        <input
          name="search"
          value={search}
          onChange={(evt) => setSearch(evt.target.value)}
        />
        <button type="submit">Search</button>
      </form>
      {currentSearch && (
        <ul>
          {pageResults.map((result) => (
            <li>
              <Link key={result.id} href={`/movie/${result.id}`}>
                {result.Title}
              </Link>
            </li>
          ))}
        </ul>
      )}
    </>
  );
};

Enhancing this for JavaScript-ready users is surprisingly straight-forward.

Because we have the logic already set in place, instead of re-implementing everything again we prevent the submit default behavior, serialize the form data and push a route change, getInitialProps handles the rest.

import Router from 'next/router';

function onSubmit(evt) {
  evt.preventDefault();
  const formData = new FormData(evt.target);
  const searchQuery = formData.get('search');
  const url = `/?search=${searchQuery}`;
  Router.push(url);
}

Relying completely on the event dispatching and its target, which both come built-in, and delegating the navigation to Next’s router keeps the client side of the code minimal.

The web does the heavy lifting, our client code is there to enhance the experience

Approaches like these aren’t seen much because we tend to build solutions with JavaScript first in mind. Shifting that initial approach changes drastically the outcome in code for similar or identical tasks, tasks as common as fetching data and URL persistence.

# Pagination of data results

Similar to how we look up inside the context parameter to extract the search query, to enable specific page results we need to inspect this object and look for a page key.

Back inside getInitialProps we check for this value in the query property and construct the correct URL to hit the service.

Index.getInitialProps = async ({ query }) => {
  const currentSearch = query.search;

  if (!currentSearch) return {};

  const currentPage = query.page ? +query.page : 1;

  const searchUrl = `//www.omdbapi.com/?s=${currentSearch}&page=${currentPage}`;

  const response = await unfetch(searchUrl);
  const results = await response.json();

  const RESULTS_PER_PAGE = 10;
  const hasNextPage = RESULTS_PER_PAGE * currentPage < results.totalResults;
  const hasPrevPage = currentPage > 1;

  return {
    pageResults,
    totalResults: results.totalResults,
    currentSearch,
    nextPage: hasNextPage ? currentPage + 1 : null,
    prevPage: hasPrevPage ? currentPage - 1 : null
  };
};

By making page an optional key we still support our initial flow as we obtain the same result with ?search=batman and ?search=batman&page=1, later in the method we use the totalResults number to determine if there’s a next page, and a previous page in case the current page is higher than one.

We use again the data returned by getInitialProps in the page component to construct those links to different results pages.

import Link from 'next/link';

const Index = (props) => {
  const { pageResults, currentSearch, prevPage, nextPage } = props;
  const [search, setSearch] = useState('');

  return (
    <>
      <form action="?" onSubmit={onSubmit}>
        <input
          name="search"
          value={search}
          onChange={(evt) => setSearch(evt.target.value)}
        />
        <button type="submit">Search</button>
      </form>
      {currentSearch && (
        <ul>
          {pageResults.map((result) => (
            <li>
              <Link key={result.id} href={`/movie/${result.id}`}>
                {result.Title}
              </Link>
            </li>
          ))}
        </ul>
      )}
      {prevPage && (
        <Link href={`/?search=${currentSearch}&page=${prevPage}`}>
          {`Page ${prevPage}`}
        </Link>
      )}
      {nextPage && (
        <Link href={`/?search=${currentSearch}&page=${nextPage}`}>
          {`Page ${nextPage}`}
        </Link>
      )}
    </>
  );
};

Link components are rendered as anchor elements, so navigation through page results will work perfectly without client code.

For users with JavaScript, links will trigger a route change in Next's router logic, passing through getInitialProps in a single page application experience.

# Wrap-up

One of the motivations for writing this was the constant battle I see around frameworks and their impact in accessibility and performance.

I don’t think frameworks are evil, though I do believe we need to advocate and educate more around the fundamentals of the web and how it works. This will help us developers make smarter decisions, write better code and create more accessible products.

Writing better HTML might help you by having to write less JavaScript in the end

Though it is a simplified case, the experience of tackling common features in a web application with a more incremental approach did produce better and simpler client code.

This as a starting point is better than breaking or reinventing web fundamentals and trying to patch them back again with even more client code.

I encourage you to explore its code base here in its repository or try the full application experience at muvi.now.sh, and to do it with JavaScript disabled.

It’s the web, built using a framework, and it just works.