Create a Podcast Player with React and AG Grid

In this post we will create a simple Podcast listening app using React. The main GUI for the app will be AG Grid so you can see how simple it is to get a prototype application up and running, leaning on the React Data Grid to do much of the heavy lifting for us. We'll build in small increments: Create a basic Data Grid Load and render an RSS Feed in the Grid Add an Audio Control to Play the podcast using a custom cell renderer Allow the user to add the Podcast URL Adding Sorting, Filtering, including filtering on data not displayed on the grid. Each increment allows us to expand on our knowledge of AG Grid and with one or two small code changes we can add a lot of value very quickly to the user. Along the way we will see some of the decision processes involved in designing the app, and learn about Controlled and Uncontrolled Components in React. This is what we will be building: Let's Create a Simple Podcast Listener in React with AG Grid You can find the source code for this project at: https://github.com/ag-grid/react-data-grid In the folder. podcast-player The root of the folder has the current version of the app, and you can run it with: podcast-player npm install npm start You do need to have as a pre-requisite. node.js installed The project contains sub-folders for the different stages listed in this post e.g. folder 'v1' is the code for the 'Version 1' section. To run any of the intermediate versions, into the subfolder and run followed by . cd npm install npm start Getting Started I created the project using . Create React App npx create-react-app podcast-player cd podcast-player This creates a bunch of extra files that I won't be using, but I tend not to delete any of these on the assumption that even if I am prototyping an application, I can go back later and add unit tests. I'm going to use the community edition of AG Grid and the AG Grid React UI and add those to my project using npm install npm install --save ag-grid-community ag-grid-react These are the basic setup instructions that you can find on the . AG Grid React Getting Started Page Version 1 - Create a Grid to Render Podcasts The first iteration of my application is designed to de-risk the technology. I want to make sure that I can create a running application that displays a page to the user with a React Data Grid containing the information I want to display. Building in small increments means that I can identify any issues early and more easily because I haven't added a lot of code to my project. We'll start by creating all the scaffolding necessary to render a grid, ready to display a Podcast. I have in mind a Data Grid that shows all the episodes in the grid with the: Title Date Playable MP3 I will amend the generated by so that it renders a , and we'll work on the during through this tutorial. App.js create-react-app PodcastGrid PodcastGrid Specify the React Data Grid Interface The temptation at this point could be to directly use the component at my level, but I want to create a simple re-usable component that cuts down on the configuration options available. AgGridReact App And this Data Grid is going to be special since it will take an as a property. To keep things simple, I'm hardcoding the RSS feed. rssfeed import './App.css'; import {PodcastGrid} from './PodcastGrid';

function App() { return ( Podcast Player ); }

export default App; Because I'm using React, and passing in the feed URL as a property, the will have the responsibility to load the RSS feed and populate the grid. PodcastGrid I'm also choosing to configure the and of the grid via properties. height width This code obviously won't work since I haven't created the component yet. But I've specified what I want the interface of the component to look and act like, so the next step is to implement it. PodcastGrid Create a React Data Grid Component I will create a file for our React Grid Component which will render podcasts. PodcastGrid.js Initially, this will just be boilerplate code necessary to compile and render a simple grid with test data. While I know that my Grid will be created with a property for the RSS Feed, I'm going to ignore that technicality at the moment and render the Grid with hardcoded data because I don't want to have to code an RSS parser before I've even rendered a Grid on the screen. I'll start simple and incrementally build the application. I'll start with the basic boilerplate for a React component, just so that everything compiles, and when I run at the command line I can see a running application and implementation of the Grid. npm start The basic React boilerplate for a component is: import React and , I usually import at the same time useState useEffect import so that I can use AG Grid as my Data Grid AgGridReact import some CSS styling for the grid import React, {useEffect, useState} from 'react'; import {AgGridReact} from 'ag-grid-react';

import 'ag-grid-community/dist/styles/ag-grid.css'; import 'ag-grid-community/dist/styles/ag-theme-alpine.css';

export function PodcastGrid(props) {

return ( ) } At this point, my Grid won't display anything, but it should be visible on the screen and I know that I have correctly added AG Grid into my React project. If anything fails, I will check my React installation, and possibly work through the or . AG Grid React Getting Started Documentation Tutorial Blog Post Rendering Data on the Grid The next step of working iteratively for me is to create a grid that will render some data, using the columns that I specified earlier. Title Date Playable MP3 I'm not going to name them like that though, I'm going to show the headings on the grid as: Episode Title Published Episode In AG Grid, I configure the columns using an array of Column Definition objects. var columnDefs = [ { headerName: 'Episode Title', field: 'title', }, { headerName: 'Published', field: 'pubDate', }, { headerName: 'Episode', field: 'mp3', } ]; And then add them to the Grid as properties. At this point, my Grid will now have headers, but will still say because I haven't supplied the Grid with any data to show in the rows. I'll hard code some data for the rows and use to store the data. [loading...] useState const [rowData, setRowData] = useState([ {title: "my episode", pubDate: new Date(), mp3: "https://mypodcast/episode.mp3"}]); My data uses the names that I added in the as the names of the properties in my . field columnDefs rowData I've added as a object to make sure that AG Grid will render the date, the title is just a and my is also just a but it represents a . pubDate Date String mp3 String Url I've created data in the format that I expect to receive it when I parse a podcast RSS feed. I'm making sure that my grid can handle the basic data formats that I want to work with as early as I can. The next thing to do is to add the data into the grid, which I can do by adding a property to the Grid. rowData My Grid will now show the hardcoded that I created, and use the column headers that I configured in the . If anything went wrong at this point I'll double-check that my were using the same names as I created as properties in my . rowData columnDefs columnDefs field rowData The benefit of doing this with hard-coded data is that when I dynamically load the data, should something go wrong, then I know it is related to the array of data dynamically generated, and not my Grid configuration. The full version of , after following these steps looks like the code below: PodcastGrid import React, {useEffect, useState} from 'react'; import {AgGridReact} from 'ag-grid-react';

import 'ag-grid-community/dist/styles/ag-grid.css'; import 'ag-grid-community/dist/styles/ag-theme-alpine.css';

export function PodcastGrid(props) {

const [rowData, setRowData] = useState([ {title: "my episode", pubDate: new Date(), mp3: "https://mypodcast/episode.mp3"}]);

var columnDefs = [ { headerName: 'Episode Title', field: 'title', }, { headerName: 'Published', field: 'pubDate', }, { headerName: 'Episode', field: 'mp3', } ];

return ( ) } The next step is to move from hard-coded data, to dynamically loading the data from an RSS Feed. version 1 code .dev version 1 code live deployed version At this point our player is very simple: Version 2 - Render an RSS feed in AG Grid The next thing I want to do is load an RSS feed into the grid. What is the Podcast RSS Format? RSS is a standard format to specify syndication data e.g. for a blog, or a podcast. The RSS feed is an XML document. See https://validator.w3.org/feed/docs/rss2.html This is a very flexible standard and has been adapted for use with Podcasts, e.g. Google has a page describing the RSS Podcast format https://support.google.com/podcast -publishers/answer/9889544 Apple also provides an RSS specification: . We can open the RSS feed that we have been using in a browser and it will render the RSS for us - https://podcasters.apple.com/support/823-podcast-requirements https://feeds.simplecast.com/tOjNXec5 This is the RSS feed for the . A podcast covering real-world experiences using JavaScript and Modern Web Development. By looking at the podcast feed in the browser we can see that, to fill the Grid, we need to pull out all the elements in the RSS feed, and then the , and details: WebRush podcast pubDate enclosure my episode Thu, 16 Sep 2021 10:00:00 +0000 The code snippet above removes most of the data from the RSS feed that we are not interested in to demonstrate the basic structure of a Podcast RSS feed. There are more fields in the data so it is worth reading the specification and looking at the raw feeds. Then you can see data that would be easy to add to the Grid when you experiment with the source code. Parsing XML in the Browser with JavaScript XML often seems painful to work with, and it might be more convenient to look for a JSON feed, but not every podcast offers a JSON feed. But XML parsing is built into most browsers, given that HTML is basically XML. We can use the from the object. You can read about the . It provides a method which will parse a String of XML or HTML and allow us to use normal operations to find the data. DOMParser window DOMParser in the MDN Web Docs parseFromString querySelector e.g. if I create a DOMParser const parser = new window.DOMParser(); I can parse an RSS feed, stored in a called . String rssfeed const data = parser.parseFromString(rssfeed, 'text/xml')) Then use normal DOM search methods to navigate the XML. I could return all the elements in the RSS feed with. item const itemList = data.querySelectorAll('item'); And from each of the s in the array, I could retrive the data: item title const aTitle = itemList[0].querySelector('title').innerHTML; I'm using the to get the value from the element. innerHTML And I can get an attribute using the normal method. getAttribute const mp3Url = itemList[0].querySelector('enclosure').getAttribute('url'); We don't need a very sophisticated parsing approach to get the data from an RSS Podcast feed. Fetching and Parsing RSS Feed Data I will want to the URL, and then parse it: fetch fetch(props.rssfeed) .then(response => response.text()) .then(str => new window.DOMParser(). parseFromString(str, 'text/xml')) This would then return an object which I can apply to: querySelector fetch(props.rssfeed) .then(response => response.text()) .then(str => new window.DOMParser(). parseFromString(str, 'text/xml')) .then(data => { const itemList = data.querySelectorAll('item'); ... Because I'm using React, I'll wrap all of this in a method which would trigger when the in the props changes. useEffect rssfeed useEffect(()=>{

fetch(props.rssfeed) ... },[props.rssfeed]); During the final of the I'll build up an array of objects which matches the test data used earlier and then to add the data to the Grid. then fetch setRowData const itemList = data.querySelectorAll('item');

const items=[]; itemList.forEach(el => { items.push({ pubDate: new Date(el.querySelector('pubDate').textContent), title: el.querySelector('title').innerHTML, mp3: el.querySelector('enclosure').getAttribute('url') }); });

setRowData(items) That's the basic theory. Now to implement it. Rendering RSS Feed in React Data Grid So I'll remove my test data: const [rowData, setRowData] = useState([]); The basic steps to loading an RSS Feed into AG Grid are: load from an RSS feed, parse the feed using DOMParser find all the elements and store in an array of item itemList iterate over the list to extract the , , and url title pubDate mp3 then add all the data into an array called items which I use to setRowData As you can see below: useEffect(()=>{

fetch(props.rssfeed) .then(response => response.text()) .then(str => new window.DOMParser().parseFromString(str, 'text/xml')) .then(data => { const itemList = data.querySelectorAll('item');

const items=[]; itemList.forEach(el => { items.push({ pubDate: new Date(el.querySelector('pubDate').textContent), title: el.querySelector('title').innerHTML, mp3: el.querySelector('enclosure').getAttribute('url') }); });

setRowData(items) });

},[props.rssfeed]); This would actually be enough to load the planned data into the Grid. Formatting the Grid And when I do I can see that it would be useful to format the grid columns. The Episode Title can be quite long so I want to make the text wrap, and format the cell height to allow all of the to render. I can configure this with some additional column definition properties. title wrapText: true, autoHeight: true, I also want the column to be resizable to give the user the option to control the rendering. Again this is a boolean property on the column definition. resizable: true, I think it would be useful to allow the user to sort the grid to find the most recent podcast. I can implement this using a property on the column. pubDate sortable: true, And then to control the column sizes, relative to each other, I will use the property to make both the and twice the size of the flex title mp3 date flex: 2, The full column definitions are below to enable, sizing, resizing and sorting. var columnDefs = [ { headerName: 'Episode Title', field: 'title', wrapText: true, autoHeight: true, flex: 2, resizable: true, }, { headerName: 'Published', field: 'pubDate', sortable: true, }, { headerName: 'Episode', field: 'mp3', flex: 2, } ]; At this point I can't play podcasts, I've actually built a very simple RSS Reader which allows sorting by published episode data. Here's the code for version 2 in : PodcastGrid.js import React, {useEffect, useState} from 'react'; import {AgGridReact} from 'ag-grid-react';

import 'ag-grid-community/dist/styles/ag-grid.css'; import 'ag-grid-community/dist/styles/ag-theme-alpine.css';

export function PodcastGrid(props) {

const [rowData, setRowData] = useState([]);

useEffect(()=>{

fetch(props.rssfeed) .then(response => response.text()) .then(str => new window.DOMParser().parseFromString(str, 'text/xml')) .then(data => { const itemList = data.querySelectorAll('item'); const items=[]; itemList.forEach(el => { items.push({ pubDate: new Date(el.querySelector('pubDate').textContent), title: el.querySelector('title').innerHTML, mp3: el.querySelector('enclosure').getAttribute('url') }); });

setRowData(items) });

},[props.rssfeed]);

var columnDefs = [ { headerName: 'Episode Title', field: 'title', wrapText: true, autoHeight: true, flex: 2, resizable: true, }, { headerName: 'Published', field: 'pubDate', sortable: true, }, { headerName: 'Episode', field: 'mp3', flex: 2, } ];

return ( ) }; The next step is to support playing the podcast. version 2 code live deployed version 2 We are now displaying the RSS details Version 3 - Play The Podcast For Version 3, to allow people to play the podcast audio, I'm going to do this as simply as possible and create a custom cell renderer for the mp3 field. AG Grid allows us to use full React Components to render cells, but rather than starting there, I will start by adding an inline to the field. cellRenderer mp3 A allows us to create custom HTML that will render in the cell. cellRenderer So instead of showing the URL text, I will display an HTML5 audio element. e.g. The simplest way to implement this is to use a directly in the column definition, and I will provide a little styling to adjust the height and vertical positioning. cellRenderer cellRenderer: ((params)=>` `) And I add this to the column definition. cellRenderer mp3 { headerName: 'Episode', field: 'mp3', flex: 2, autoHeight: true, cellRenderer: ((params)=>` `) } Making the grid now a functional Podcast player. version 3 code .dev version 3 code live deployed version 3 After adding the audio player: Version 4 - Customising the RSS Feed The RSS Feed is still hardcoded, so the next step is to allow the feed URL to be customized. Once again, I'll do the simplest thing that will work so I'll add a text field with a default value in the . App.js My first step is to 'reactify' the App and have the RSS URL stored as state. I'll add the necessary React imports: import React, {useState} from 'react'; Then set the state to our hardcoded default. const [rssFeed, setRssFeed] = useState("https://feeds.simplecast.com/tOjNXec5"); And use the rssFeed state in the JSX to setup the property for the : PodcastGrid <PodcastGrid rssfeed = {rssFeed} Giving me an that looks like this: App.js import './App.css'; import React, {useState} from 'react'; import {PodcastGrid} from './PodcastGrid';

function App() {

const [rssFeed, setRssFeed] = useState("https://feeds.simplecast.com/tOjNXec5");

return ( Podcast Player ); }

export default App; The simplest way I can think of to make this configurable is to add an input field, with a button to trigger loading the feed. RSS Feed URL: Load Feed Note that I'm using in the JSX so that once the value has been set by React, the DOM is then allowed to manage it from then on. If I had used then I would have to take control over the change events. By using I'm doing the simplest thing that will work to add the basic feature. defaultValue value defaultValue Also, when working with JSX I have to use instead of in the element. htmlFor for label And to handle the button click: const handleLoadFeedClick = ()=>{ const inputRssFeed = document.getElementById("rssFeedUrl").value; setRssFeed(inputRssFeed); } Now I have the ability to: Type in a Podcast RSS Feed URL Click a button Load the feed into a React Data Grid Play the podcast episode Sort the feed to order the episodes For your reference: version 4 code .dev version 4 code live deployed version 4 Now with the ability to add a URL: Testing Library App.test.js One thing to do at this point is to amend the class. A full introduction to the is beyond the scope of this tutorial, but we can keep the default test created by working. App.test.js React Testing Library create-react-app By default the creates a single test for the component. This is in the file. Having changed if we run we will be told that our project is failing to pass its test. create-react-app App.js App.test.js App.js npm test This is because the default test checks the header displayed on the screen. import { render, screen } from '@testing-library/react'; import App from './App';

test('renders learn react link', () => { render( ); const linkElement = screen.getByText(/learn react/i); expect(linkElement).toBeInTheDocument(); }); The default test, shown above: Is called . renders learn react link Renders the component. App Gets the element on the screen which contains the text "learn react". Asserts that the element (linkElement) is present, and if not, fails the test. Because I changed the output from the , and even though I'm not doing TDD, I can still amend the test to keep the project build working. App.js I amended the test to be: test('renders the app', () => { render( ); const headerElement = screen.getByText(/Podcast Player/i); expect(headerElement).toBeInTheDocument(); }); This finds the header title and asserts that it is in the document. Admittedly it isn't much of a test, but it keeps the tests running until we are ready to expand them out to cover the application behavior. CORS This RSS reader will not work with all Podcast feeds. Cross-Origin Resource Sharing (CORS) has to be configured to allow other sites to the data from a browser. Some Podcasts may be on hosting services that do not allow browser-based JavaScript to access the feed. fetch If a feed does not load, then have a look in your browser console and if you see a message like then you know that the site has not been configured to allow websites to pull the RSS feed. blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. Most Podcast feed based applications are not browser based so they don't encounter this limitation. I've listed a few of our favorite JavaScript and technical podcast feeds below, so if you want to experiment with the Podcast player application, you don't have to hunt out a bunch of feed URLs. WebRush https://feeds.simplecast.com/tOjNXec5 The Change Log https://changelog.com/podcast/feed The Evil Tester Show https://feed.pod.co/the-evil-tester-show JS Party https://changelog.com/jsparty/feed Founders Talk https://changelog.com/founderstalk/feed Version 5 - Searching and Filtering Having used the app, I realized that I really wanted some sort of searching and filtering functionality to find episodes on a specific topic. The easiest way to add that quickly is to add a 'filter' to the columns. Filter on Title The is a so I can use an in-built AG Grid filter to allow me to text search and filter the data in the title column. The built-in text filter is called and I add it to the column definition as a property: title String agTextColumnFilter filter: `agGridTextFilter` The column definition now looks as follows: title var columnDefs = [ { headerName: 'Episode Title', field: 'title', wrapText: true, autoHeight: true, flex: 2, resizable: true, filter: `agGridTextFilter` }, This provides me with an out-of-the-box searching and filtering capability for the data in the title. Filter on Date Since it is no extra work for me, I'm going to add a . There is an inbuilt Date filter in AG Grid, the which I can add as a property to the column. filter to date agDateColumnFilter pubDate { headerName: 'Published', field: 'pubDate', sortable: true, filter: 'agDateColumnFilter' }, With this property added, the user now has the ability to search for podcasts for date ranges. Text Filter on Description The titles of podcasts don't contain as much information as the description. It would be useful to allow searching through the description as well. The easiest way to add that would be to create a description column and then allow filtering on the column. I iterated through a few experiments before finding one approach I liked. Display the full description from the RSS feed Use to display description HTML in the cell cellRenderer Strip HTML tags from RSS feed data Show a subset of data using a valueFormatter Use a Quick Filter Display the full description from the RSS feed I added an additional parsing query in the rss to create a property. fetch description description: el.querySelector('description') .textContent And then added a column to my Data Grid. While that worked, the problem is that the description can often be rather large and has embedded HTML formatting. Description { headerName: 'Description', field: 'description', wrapText: true, autoHeight: true, flex: 2, resizable: true, filter: `agGridTextFilter` }, The resulting Grid wasn't very aesthetic. Use to display HTML in the cell cellRenderer Since the data that is retrieved in the description is HTML, I could render the HTML directly in the table by creating a . By default, the cell shows the data values as text. The output from a is rendered as HTML. cellRenderer cellRenderer Adding a property causes the cell to render the supplied HTML, but this was often too large and had embedded images. cellRenderer cellRenderer: ((params)=>params.value) Strip HTML tags from RSS feed data My next thought was to strip all the HTML tags out of the description and render the raw text. I could do that by removing the and adding a regex when parsing the description field. cellRenderer descriptionTxt: el.querySelector('description') .textContent.replace(/( ]+)>)/gi, ''), This was the best option so far, but still showed too much text in the cell. Show a subset of data using a valueFormatter The filter for the columns operates on the rowData, not the displayed data, so I could still use a column filter and simply cut down on the data displayed to the user. I could do that by using a rather than a . valueFormatter cellRenderer A amends the value and returns it as a to display on the grid. The returns HTML. By showing only a trimmed version of the description, the cell in the Data Grid does not get too large but still gives me the ability to filter on the complete text. valueFormatter String cellRenderer valueFormatter: params => params.data.description.length>125 ? params.data.description.substr(0,125) + "..." : params.data.description This would give me a column definition of: description { headerName: 'Description', field: 'description', wrapText: true, autoHeight: true, flex: 2, resizable: true, filter: `agGridTextFilter`, valueFormatter: params => params.data.description.length>125 ? params.data.description.substr(0,125) + "..." : params.data.description }, Use a QuickFilter A quick filter is a filtering mechanism that matches any of the data in the Data Grid's row data. e.g. using would match any row with "testing" in the or field. The data does not even have to be rendered to the Data Grid itself, it just has to be present in the data. So I could remove the description column and just add an input field to search the contents. That would make the whole grid simpler and the user experience cleaner. api.setQuickFilter("testing"); title description I'll start by removing the from the , but keeping the description data in the , and I'll use the version with the HTML tags stripped because we are using a text search. description columnDefs rowData description: el .querySelector('description') .textContent.replace(/( ]+)>)/gi, ''), }); #App.js changes for QuickFilter I first need to make changes to the to add a 'search' input box. App.js Quick Filter: I then need to create the state for and write a function that will store the state when we change it in the input field. quickFilter handleFilterChange const [quickFilter, setQuickFilter] = useState(""); And then write the function. handleFilterChange const handleFilterChange = (event)=>{ setQuickFilter(event.target.value); } The next step is to pass the quick filter text to the as a new property. PodcastGrid Use QuickFilter API in React Data Grid The component has not yet needed to use the AG Grid API, everything has been achieved through properties on the Grid or the Column Definitions. To be able to access the API I need too hook into the Data Grid's event, and store the API access as state. PodcastGrid onGridReady I'll create the state variable first: const [gridApi, setGridApi] = useState(); Then amend the Grid declartion to hook into the callback. onGridReady The handler will store a reference to the Grid API: onGridReady const onGridReady = (params) => { setGridApi(params.api); } Finally, to use the props variable that has been passed in: quickFilter useEffect(()=>{ if(gridApi){ gridApi.setQuickFilter(props.quickFilter); } }, [gridApi, props.quickFilter]) And add the data, to the grid as a hidden column: description { field: 'description', hide: true }, When the has been set, and the property changes, we will call the method on the API to filter the Grid. This provides a very dynamic and clean way of identifying podcasts that include certain words in the description. gridApi quickFilter setQuickFilter Find online: version 5 code .dev version 5 code live deployed version 5 Ability to search and filter podcasts: Version 6 - Pagination After using the app I realized that with so many podcast episodes in a feed, having all of the episodes in a single table was useful but I would have preferred the ability to page through them, and I'd like to see a count of all of the podcast episodes that are available in the feed. Fortunately, we can get all of that functionality from a single AG Grid property. pagination The property applies to the Grid. I can add it in the Grid declaration: This immediately shows me the count of podcast episodes available and makes navigating through the list easier. I also want to take advantage of another feature of the AG Grid pagination and set the page size, the default page size is 100, and 10 seems better for this app: paginationPageSize={10} Or I could allow the Grid to choose the best page size for the data and the size of the grid: paginationAutoPageSize={true} Again, I've only added a few extra properties to the Data Grid, but have immediately made the application more usable, with the minimal development effort. Find online: version 6 code .dev version 6 code live deployed version 6 Pagination added: Version 7 - Podcast List I think it would be useful to create a list of podcasts that I listen to, so I don't have to type in the URL each time. Initially, this will be a hard-coded list, but longer-term it would add more benefit to the user if the list was persisted in some way, either in Local Storage or some online mechanism. But since this tutorial is about getting as much value out to the user with as little coding effort as we can, I'll start with a dropdown. My initial thought is to create a drop-down and then set the RSS Feed input with the value: Choose a podcast: WebRush The Evil Tester Show To do that I will need to change my app from using an , to a . uncontrolled component controlled component Editing Input Field Value with React The current implementation for the RSS Feed input is uncontrolled: Once loaded the state of the input field is managed by the browser through normal user interaction The value in the input field is set using . This is only available to programmatic control during initial setup. defaultValue We want the drop down selection to change the of the input field value To do that, we need to write the event handlers to manage the input field state. I'll create a state for to distinguish it from the which is set when the user clicks the button. inputFeedUrl rssFeed Load Feed const [inputFeedUrl, setInputFeedUrl] = useState("https://feeds.simplecast.com/tOjNXec5"); Then change the text input to a controlled component by setting the with the state, rather than the . value defaultValue The input field is now a controlled component and is read only because we haven't added any handling. onChange setInputFeedUrl(event.target.value)}/> The drop-down for Choose a podcast can now use the state handler to set the . inputFeedUrl setInputFeedUrl(event.target.value)}> Now we have an field controlled with React to allow the user to input an RSS Url, and which we can change the value of from a drop-down of hardcoded feed URLs. input Loading a Select element option from an Array It will be easier to maintain the drop-down if the values were taken from an array. This would also open up the application to amending the URLs more easily at run time. const [feedUrls, setFeedUrls] = useState( [ {name: "WebRush", url:"https://feeds.simplecast.com/tOjNXec5"}, {name: "The Evil Tester Show", url:"https://feed.pod.co/the-evil-tester-show"}, ] ); Because JSX supports arrays we can directly convert this array into a set of elements. feedUrls option {feedUrls.map((feed) => {feed.name} )} I add a property because when creating JSX components from an array, React uses the property to help determine which parts of the HTML need to be re-rendered. The final thing to do is to set the selected value in the options based on the . key key inputFeedUrl If I was using JavaScript directly then I would set the attribute on the option. selected {feedUrls.map((feed) => {feed.name} )} With React and JSX, to set the selected value for a we set the of the element. select value select setInputFeedUrl(event.target.value)}> The full JSX for the podcast drop down looks like this: Choose a podcast: setInputFeedUrl(event.target.value)}> {feedUrls.map((feed) => {feed.name} )} Now it is easier to build up a list of recommended podcasts, which we know have feeds that are CORS compatible: WebRush The Evil Tester Show The Change log JS Party Founders Talk I do recommend some other excellent podcasts but they I couldn't find a CORS compatible RSS feed e.g. JavaScript Jabber My final looks like the following App.js import './App.css'; import React, {useState} from 'react'; import {PodcastGrid} from './PodcastGrid';

function App() {

const [inputFeedUrl, setInputFeedUrl] = useState("https://feeds.simplecast.com/tOjNXec5"); const [rssFeed, setRssFeed] = useState(""); const [quickFilter, setQuickFilter] = useState(""); const [feedUrls, setFeedUrls] = useState( [ {name: "WebRush", url:"https://feeds.simplecast.com/tOjNXec5"}, {name: "The Evil Tester Show", url:"https://feed.pod.co/the-evil-tester-show"}, {name: "The Change log", url:"https://changelog.com/podcast/feed"}, {name: "JS Party", url: "https://changelog.com/jsparty/feed"}, {name: "Founders Talk", url:"https://changelog.com/founderstalk/feed"} ] );

const handleLoadFeedClick = ()=>{ const inputRssFeed = document.getElementById("rssFeedUrl").value; setRssFeed(inputRssFeed); }

const handleFilterChange = (event)=>{ setQuickFilter(event.target.value); }

return ( Podcast Player Choose a podcast: setInputFeedUrl(event.target.value)}> {feedUrls.map((feed) => {feed.name} )} RSS Feed URL: setInputFeedUrl(event.target.value)}/> Load Feed Quick Filter: ); }

export default App; Find online: version 7 code .dev version 7 code live deployed version 7 With a list of podcasts: Summary Obviously, there is a lot more that we can improve, but so long as you type in the correct URL, and the URL feed supports CORS access from other sites then, this is a very simple podcast reader. We saw that AG Grid made it very easy to experiment with different ways of filtering and interacting with the data, and I was able to explore alternatives with minimal development time. Most of the functionality I was adding to the application was via out-of-box Data Grid features configured through properties. When we did need slightly more interactive functionality, the API was easy to get hold of. What we learned: Incremental development using AG Grid. Using fetch to populate an AG Grid. Using AG Grid in React. Adding a cell renderer in the column definitions. Parsing RSS and XML using . DOMParser Impact of Cross-Origin Resource Sharing (CORS) from JavaScript. Some top podcasts to listen to. Filtering column data. Using the AG Grid API in react. operates on all rowData, not just the displayed data. quickFilter Adding pagination and row count to a Data Grid. To learn more about . You can find all the source code on Github: AG Grid and the React UI code The player was built iteratively and you can try each version: use v1 use v2 use v3 use v4 use v5 use v6 use v7 Since this article is quite long, we created two videos walking through the process: 2TDIWOubvp0 https://www.youtube.com/watch?v= https://www.youtube.com/watch?v=rsamoG6bD4Y