I recently fabricated this 'Tag-Text-Search' functionality for my blog. So, here is a little article just about it.

BTW, the source code for the blog is public and you can surely go check it here.

In this blog, we'll be using Context API to make the setup work. So, go ahead if you have a basic understanding of it and if not, you can definitely go have a look at my article on Using React Context API Like a Pro

Hope you enjoy :)

Setup

Run the following commands to have an initial setup to work on.

npx create-react-app tag-text-search
cd tag-text-search
yarn start

Final File Structure

The Side Bar

I think it is better to start with creating a side bar that shall contain the search bar and the tags.

src/sideBar/sideBar.js

import SearchBar from './searchBar';
import TagSection from './tagSection';
import styles from '../../styles/sideBar.module.css';

export default function SideBar() {
  return (
    <div className={styles.stickyContainer}>
      <div className={styles.container}>
        <SearchBar />
        <TagSection />
      </div>
    </div>
  );
}

We'll be creating the sideBar.module.css in a moment. But let's first finish off the SerachBar and the TagSection

Wait, no! As a matter of fact, let's be done with all the styling right now right here.
Here you go, paste the code below in src/styles/sideBar.module.css

.stickyContainer {
  position: -webkit-sticky;
  position: sticky;
  top: 0px;
  height: 0;
  z-index: 20;
  width: 30%;
  max-width: 30%;
}

.container {
  position: absolute;
  z-index: 20;
  display: inline-block;
  height: 100vh;
  left: 20px;
  padding: 1rem;
  top: 0;
  background: var(--baseLight);
  border-radius: 2px;
  z-index: 10;
  transition: 0.8s;
}

.sb__container {
  background: var(--base);
  border-radius: 2px;
  transition: 0.4s;
  margin: 2rem 0;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  border: 2px solid transparent;
  width: 100%;
}

.sb__container:focus-within {
  background: var(--baseLight);
  border: 2px solid var(--primary);
}

.sb__container svg {
  margin-left: 0.5rem;
  padding-top: 0.2rem;
}

.sb__input {
  font-family: Antonio;
  background: var(--base);
  outline: none;
  color: var(--primary);
  font-size: 1rem;
  letter-spacing: 0.5px;
  width: 100%;
  padding: 5px;
  border: none;
  transition: 0.4s;
}

.sb__input:focus-within {
  background: var(--baseLight);
}

.sb__input::placeholder {
  color: var(--primary);
}

.ts__flexContainer {
  position: relative;
  display: flex;
  justify-content: center;
  width: 100%;
  flex-direction: column;
}

.ts__heading {
  text-transform: capitalize;
  font-size: 1.7rem;
}

.ts_selectedTagContainer {
  margin-bottom: 1.5rem;
  margin-top: 0.3rem;
}

.ts__unselectedTagContainer {
  overflow-y: auto;
  height: 100%;
  margin-top: 0.3rem;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.ts__selectedTag {
  cursor: pointer;
  margin: 0.2rem 0;
  margin-right: 0.4rem;
  position: relative;
  color: black;
  border: 2px solid var(--primary);
  padding: 5px 15px;
  overflow: hidden;
  transition: 1s all ease;
  background: transparent;
  font-family: Antonio;
  font-weight: bold;
  letter-spacing: 0.04em;
  border-radius: 2px;
  outline: none;
  background: var(--primary);
  font-size: 1rem;
}

.ts__unselectedTag {
  cursor: pointer;
  margin: 0.5rem 0;
  position: relative;
  color: var(--primary);
  border: 2px solid var(--primary);
  padding: 5px 15px;
  overflow: hidden;
  transition: 1s all ease;
  background: transparent;
  font-family: Antonio;
  font-weight: bold;
  letter-spacing: 0.04em;
  border-radius: 2px;
  outline: none;
  background: var(--base);
  font-size: 1rem;
}

This has all the styles we would be needing for the SideBar , the SearchBar, and the TagSection.

As you can see we are using a couple of CSS variables so we better create them as well.

Paste this code in src/index.css

:root {
  --base: #e3e3e3;
  --baseLight: #c8c7c7;
  --primary: #f1762d;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

code {
  font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New',
    monospace;
}

Search Bar

I do have a blog that is just based on this search functionality, in case you want to check that out. Implement Search Bar in React for Ecommerce Website

Alright now, let's code the SearchBar. It is pretty straightforward as opposed to the TagSection

Just copy the code below in src/components/sideBar/serachBar.js

import { useContext } from 'react';
import { SearchContext } from '../../store/search-context';
import styles from '../../styles/sideBar.module.css';

const SearchBar = () => {
  const { query, searchHandler } = useContext(SearchContext);

  return (
    <div className={styles.sb__container}>
      <svg
        width='16'
        height='16'
        viewBox='0 0 16 16'
        fill='none'
        xmlns='http://www.w3.org/2000/svg'
      >
        <path
          d='M10.9167 9.66667H10.2583L10.025 9.44166C10.8417 8.49166 11.3333 7.25833 11.3333 5.91667C11.3333 2.925 8.90833 0.5 5.91667 0.5C2.925 0.5 0.5 2.925 0.5 5.91667C0.5 8.90833 2.925 11.3333 5.91667 11.3333C7.25833 11.3333 8.49166 10.8417 9.44166 10.025L9.66667 10.2583V10.9167L13.8333 15.075L15.075 13.8333L10.9167 9.66667ZM5.91667 9.66667C3.84167 9.66667 2.16667 7.99167 2.16667 5.91667C2.16667 3.84167 3.84167 2.16667 5.91667 2.16667C7.99167 2.16667 9.66667 3.84167 9.66667 5.91667C9.66667 7.99167 7.99167 9.66667 5.91667 9.66667Z'
          fill='#F1762D'
        />
      </svg>
      <input
        className={styles.sb__input}
        placeholder='Search'
        type='text'
        onChange={e => searchHandler(e.target.value)}
        value={query}
      />
      <span>
        <i></i>
      </span>
    </div>
  );
};

export default SearchBar;

Now, we still have one thing that we need to create to make this work, SearchContext. So let's get on with it.

Search Context

The idea is, you define a state and the setState function in the Context and now you can essentially 'get the state' or 'update the state' from any of the components wrapped in the Context (whole application mostly :))

Paste the code below in src/store/search-context.js

import { useState, createContext } from 'react';

export const SearchContext = createContext({
  query: '',
  searchHandler: () => {},
});

const SearchContextProvider = props => {
  const [query, setQuery] = useState('');

  const searchHandler = query => {
    setQuery(query.toLowerCase());
  };

  return (
    <SearchContext.Provider
      value={{ query: query, searchHandler: searchHandler }}
    >
      {props.children}
    </SearchContext.Provider>
  );
};

export default SearchContextProvider;

Time to look at searchBar.js and serach-context.js simultaneously.

The state that is being updated by the onChange function on the input in the serachBar.js is the state defined in the context, i.e. query, and the function that is updating the state is also coming from the context, i.e. searchHandler.

We are all set but one thing. We never wrapped our application with the context. The way I like to do this is by creating an index.js in src/store and export a component named Context.

Here, paste the code below in src/store/index.js

import SearchContextProvider from './search-context';

export default function Context({ children }) {
  return (
    <SearchContextProvider>
      {children}
    </SearchContextProvider>
  );
}

The reason I like to do this is because I can create multiple contexts in multiple files and then combine them all in this file. (You'll see this later when we create the filter-context.js for tag filtering functionality)

Finally, we need to wrap our application with this context.

Paste this code in src/App.js

import SideBar from './components/sideBar/sideBar';
import Context from './store';

function App() {
  return (
    <Context>
      <SideBar />
    </Context>
  );
}

export default App;

Tag Section

Alright now! Let me lay out the concept behind this functionality.

Essentially there are two lists

1. Unselected Tags
2. Selected Tags

Initially, we put all the tags in the 'Unselected Tags' list and keep the 'Selected Tags' list empty.

Then we create two functions namely, selectTagHandler and unselectTagHandler. The selectTagHandler puts the selected tag into the 'Selected Tags' list and removes it from the 'Unselected Tags' list, and the unselectTagsHandler does exactly the opposite.

Finally, both of these functions update the fillter-contenxt (that we'll be creating shortly) with the 'Selected Tags' list for us to access later and use to filter articles. But more on that later. Okay, enough formulation! Let's jump right into creating the Tag Section

At first, let's have the TAGS array.

Paste this into src/data/data.js

export const TAGS = [
  'react',
  'books-notes',
  'web-dev',
  'design',
  'javascript',
  'reactnative',
  'mobile-dev',
];

Paste the code below into src/components/sideBar/tagSection.js

import { useState } from 'react';
import { TAGS } from '../../data/data';
import styles from '../../styles/sideBar.module.css';

export default function TagSection() {
    // 1.
  const [unselectedTags, setUnselectedTags] = useState(TAGS);
  const [selectedTags, setSelectedTags] = useState([]);

    // 2.
  const selectTagHandler = tag => {
    const updatedSelectedTags = selectedTags.concat(tag);
    setSelectedTags(updatedSelectedTags);
    setUnselectedTags(
      unselectedTags.filter(unselectedTag => unselectedTag !== tag)
    );
  };

// 3.
  const unselectTagHandler = tag => {
    setUnselectedTags(unselectedTags.concat(tag));
    const updatedSelectedTags = selectedTags.filter(
      selectedTag => selectedTag !== tag
    );
    setSelectedTags(updatedSelectedTags);
  };

  const selectedTagsList = selectedTags.map(tag => (
    <button
      className={styles.ts__selectedTag}
      key={tag}
      onClick={() => unselectTagHandler(tag)}
    >
      #{tag}
    </button>
  ));

  const unselectedTagsList = unselectedTags.map(tag => (
    <button
      key={tag}
      className={styles.ts__unselectedTag}
      onClick={() => selectTagHandler(tag)}
    >
      #{tag}
    </button>
  ));

  return (
    <div className={styles.ts__flexContainer}>
      <div className={styles.ts__flexContainer}>
        <h2 className={styles.ts__heading}>You Selected</h2>
        <div className={styles.ts_selectedTagContainer}>{selectedTagsList}</div>
      </div>
      <div className={styles.ts__flexContainer}>
        <h2 className={styles.ts__heading}>To Select From</h2>
        <div className={styles.ts__unselectedTagContainer}>
          {unselectedTagsList}
        </div>
      </div>
    </div>
  );
}

Let's break it down.

1. Firstly we create two arrays (or lists), unselectedTags and selectedTags. You'll notice that the unselectedTags is prepopulated with the TAGS array just like we planned, and the selectedTags is empty.
2. selectTagHandler takes an argument tag and uses that to populate selectedTags array using the .concat method that comes with the JS Arrays. Now we also need to remove the selected tag from the unselectedTags array and for that, we use the .filter method, again, that comes with the JS Arrays.
3. unselectTagHandler does exactly the opposite of the function we just discussed, i.e. selectTagHandler. Takes an argument, named tag - updates the unselectedTags array with it - remove it out from the selectedTags array.

Creating the filter context

As you have witnessed all the logic related to state management is right here in the TagSection component. But, in order to filter out articles based on the selected tags we need access to the selectedTags array. To achieve this we create the filter-context in which we basically keep a copy of selectedTags array. So when we update the selectedTags array in the TagSection we also update the state in our filter context.

I'll show you how!

Paste the code below in src/store/filter-context.js

import { useState, createContext } from 'react';

export const FilterContext = createContext({
  tags: [],
  tagSelector: () => {},
});

const FilterContextProvider = props => {
  const [tags, setTags] = useState([]);

  const tagSelector = tagsList => {
    setTags(tagsList);
  };

  return (
    <FilterContext.Provider value={{ tags: tags, tagSelector: tagSelector }}>
      {props.children}
    </FilterContext.Provider>
  );
};

export default FilterContextProvider;

Pretty straightforward, right. Whatever you pass (essentially a list) to the tagSelector function, is used to update the state tags. This is the state that we'll be using later in another component to filter out articles.

But this is not done yet, firstly we shall wrap our application with this context.

Paste the code below into src/store/index.js

import SearchContextProvider from './search-context';
import FilterContextProvider from './filter-context';

export default function Context({ children }) {
  return (
    <SearchContextProvider>
      <FilterContextProvider>{children}</FilterContextProvider>
    </SearchContextProvider>
  );
}

And secondly we need to add an extra bit of logic to our happy little rainbow-colored TagSection component.

Just paste the whole code into src/components/sideBar/tagSection.js and I'll explain the added lines just below it.

import { useState, useContext } from 'react';
import { TAGS } from '../../data/data';
import { FilterContext } from '../../store/filter-context';
import styles from '../../styles/sideBar.module.css';

export default function TagSection() {
    // 1.
  const filterContext = useContext(FilterContext);

  const [unselectedTags, setUnselectedTags] = useState(TAGS);
  const [selectedTags, setSelectedTags] = useState([]);

  const selectTagHandler = tag => {
    const updatedSelectedTags = selectedTags.concat(tag);
    setSelectedTags(updatedSelectedTags);
    setUnselectedTags(
      unselectedTags.filter(unselectedTag => unselectedTag !== tag)
    );
        // 2.
    filterContext.tagSelector(updatedSelectedTags);
  };

  const unselectTagHandler = tag => {
    setUnselectedTags(unselectedTags.concat(tag));
    const updatedSelectedTags = selectedTags.filter(
      selectedTag => selectedTag !== tag
    );
    setSelectedTags(updatedSelectedTags);
    // 3.
    filterContext.tagSelector(updatedSelectedTags);
  };

  const selectedTagsList = selectedTags.map(tag => (
    <button
      className={styles.ts__selectedTag}
      key={tag}
      onClick={() => unselectTagHandler(tag)}
    >
      #{tag}
    </button>
  ));

  const unselectedTagsList = unselectedTags.map(tag => (
    <button
      key={tag}
      className={styles.ts__unselectedTag}
      onClick={() => selectTagHandler(tag)}
    >
      #{tag}
    </button>
  ));

  return (
    <div className={styles.ts__flexContainer}>
      <div className={styles.ts__flexContainer}>
        <h2 className={styles.ts__heading}>You Selected</h2>
        <div className={styles.ts_selectedTagContainer}>{selectedTagsList}</div>
      </div>
      <div className={styles.ts__flexContainer}>
        <h2 className={styles.ts__heading}>To Select From</h2>
        <div className={styles.ts__unselectedTagContainer}>
          {unselectedTagsList}
        </div>
      </div>
    </div>
  );
}

Let's break it down

1. Here we are storing the object returned by the FilterContext in a constant named filterContext.
2. And, now we are passing the same exact array to the filterContext.tagSelector function that we passed to setSeletectTagsarray. Hence this makes a copy of the array selectedTags in the filter-context, namely tags array.

Phew! we are almost done. Only thing left to do is, Creating an articles array - Creating a component to render those articles - And before that, filtering them using tags and the search query.

Main Content

Alright now, this will probably feel less overwhelming so let's be done with it.

Styling first, shall we?

Paste this code in src/styles/mainContent.module.css

.container {
  width: 70%;
  margin-left: auto;
}

.thumbnailContainer {
  padding: 2rem 2rem;
  background-color: gray;
  border-radius: 10px;
  margin: 2rem;
  display: inline-block;
  width: 200px;
}

Now, let's create an ARTICLES array. Paste the code below in src/data/data.js

export const ARTICLES = [
  {
    id: '1',
    title: 'Using React Context API Like a Pro',
    body: 'If you\'ve been hearing the term "Context API" and feel totally confused about it (like me, some days ago) or you have no clue what this even means, look no further! I\'ve got you covered (for the most part, I believe)',
    tags: ['react', 'web-dev', 'javascript'],
  },
  {
    id: '2',
    title: 'Never Split the difference - Book Notes',
    body: 'If you\'ve been hearing the term "Context API" and feel totally confused about it (like me, some days ago) or you have no clue what this even means, look no further! I\'ve got you covered (for the most part, I believe)',
    tags: ['books-notes'],
  },
  {
    id: '3',
    title: 'Design in React',
    body: 'If you\'ve been hearing the term "Context API" and feel totally confused about it (like me, some days ago) or you have no clue what this even means, look no further! I\'ve got you covered (for the most part, I believe)',
    tags: ['design', 'react', 'javascript', 'web-dev'],
  },
  {
    id: '4',
    title: 'Design in React Native',
    body: 'If you\'ve been hearing the term "Context API" and feel totally confused about it (like me, some days ago) or you have no clue what this even means, look no further! I\'ve got you covered (for the most part, I believe)',
    tags: ['design', 'react', 'reactnative', 'javascript', 'mobile-dev'],
  },
];

export const TAGS = [
  'react',
  'books-notes',
  'web-dev',
  'design',
  'javascript',
  'reactnative',
  'mobile-dev',
];

Alright, we are almost done. Paste the code below into src/components/mainContent.js

import { useContext } from 'react';
import { SearchContext } from '../store/search-context';
import { FilterContext } from '../store/filter-context';
import styles from '../styles/mainContent.module.css';

export default function MainContent({ articles }) {
  const searchContext = useContext(SearchContext);
  const { tags } = useContext(FilterContext);
  let filteredArticles = null;
  if (articles) {
    // 1. Tag Search
    filteredArticles = articles.filter(article => {
      if (tags.length === 0) {
        return article;
      }
      if (tags.some(val => article.tags.includes(val))) {
        return article;
      } else {
        return null;
      }
    });

    // 2. Text Search
    filteredArticles = filteredArticles.filter(article => {
      if (article.title.toLowerCase().includes(searchContext.query)) {
        return article;
      } else {
        return null;
      }
    });
  }

  return (
    <div className={styles.container}>
      {filteredArticles !== null &&
        filteredArticles.map(article => {
          return (
            <div className={styles.thumbnailContainer} key={article.id}>
              <h2>{article.title}</h2>
            </div>
          );
        })}
    </div>
  );
}

Let's break it down. We are calling both our contexts and retrieving both the querystate and tags state.

1. Firstly, we filter the articles using tags. If tags.length === 0, in other words, if no tag is selected → return all the articles. if tags.some(val => article.tags.includes(val)), i.e. if any of the tags selected are there in the tags array associated with the article object → return that article otherwise → return nothing.
2. Secondly, we are further filtering the articles based on the search query. If (article.title.toLowerCase().includes(searchContext.query)), in other words, if a part of the title of the article matches with the search query (no matter the casing) → return that article otherwise → return nothing.

Alright, let's import this component into App.js, pass the articles and finish the remaining coffee (at least for me :)).

Paste the code below in App.js

import SideBar from './components/sideBar/sideBar';
import Context from './store';
import MainContent from './components/mainContent';
import { ARTICLES } from './data/data';

function App() {
  return (
    <Context>
      <SideBar />
      <MainContent articles={ARTICLES} />
    </Context>
  );
}

export default App;

There you have it. An ugly-looking but working 'tag-text-search' functionality. If you want to see it in action, do visit my blog (in case you aren't already on it :)

Thank you for reading!

Would love to hear you thoughts on this!