Reactive Weather ☀️

A new startup, Reactive weather, has hired you to build a web application that renders real time weather data for cities around the world. This project will require that you utilize:

• Components
• Props
• State
• Conditional Rendering
• Controlled Inputs
• fetch and the useEffect Hook

Part 1: React Components and Props

GOAL: An array of weather data has been provided for you in data.js. Render a WeatherCard in App.js for each city in the array and render the data for each city in the WeatherCard.

1. In the root directory, run the following to preview the app. This will refresh every time you save a file.

   npm install
   npm start

2. In WeatherCard.js, a card has been made for you, but hasn't been exported. Export the card using module.exports.
3. In App.js, import:
   • The cities array from data.js.
   • The WeatherCard from /components/WeatherCard.js.
4. Inside the <div className = "app">, use a map() function to iterate through the cities array and return a WeatherCard component for each item in the array. Each WeatherCard component should receive the corresponding object with a key of data.
5. In components/WeatherCard.js, update the function WeatherCard with a props parameter.
6. Update the WeatherCard so that it renders the:
   • City name
   • Temperature
   • Forecasted weather conditions

Part 2: React State and Conditional Rendering

GOAL: Complete the following using your knowledge of state and conditional rendering:

• Adjust the icons to render based on the value stored in forecast (e.g. if it is rainy the rainy icon will render).
• Create a myLocation component to track the users current location and stores the value in state. This component will update with the weather for the users specific location. We will dynamically update this in future sections!

In components/WeatherCard.js:

1. There are three additional weather icons available in the assets folder. Import these at the top of the file just like the sunny icon.
2. Conditionally render the icons based on the value stored in props.data.forecast. E.g. If it is "Rainy" than the rainy icon should render. There are multiple ways in which to achieve this output!

In App.js:

We will be updating this state variable in Part 3. Today we are just working on setting up the functionality for hard coded state values.

1. At the top of the file, import useState from the React library.
2. Create a new state variable called location and state setter function. Initialize it with a value for the city of your choice.
3. In the components folder, create a Location.js file. Import this into App.js.
4. Pass the data, location, and state setter function as props to the Location component.

In components/Location.js:

1. We need to search the data array passed as a prop to find the object that has the city that matches our location state. Explore how to use .find() to achieve this.
2. Once you have found the corresponding data, return a card similar to the one in WeatherCard.js. It can look similar to the card below.
   • NOTE: It may help to turn the icon conditional rendering you wrote into a helper function and import it into this component so that you can use DRY principles.

Part 3: Controlled Inputs

GOAL: Create a Form component that allows users to input their city and the program will output either:

1. The weather for the city they input
2. Some message informing the user that city is not in the array.

In App.js:

1. In the components folder, create a Form.js file. Import this into App.js.
2. Render the Form component near the top of your application. Pass it the location state and setLocation state setter function as props.

In components/Form.js:

1. Destructure the location and setLocation props.

2. Return a <form> element that has an <input> element that will accept a city input and <button> element. Feel free to create your own or you can use the template code below:

   <div className = "form">
       <form>
           <label className = "city">City:
               <input type="text"/>
           </label>
           <button 
               className = "btn btn-primary" 
               type="submit"
           >Submit</button>
       </form>
   </div>

3. Assign the <input> a value of location and create an onChange event handler that sets the location to the current value of the <input> using e.target.value.

Try out your form. Oh no! There's an error. Why? Currently the location state is updating every time you type and this is causing the application to error out.

4. Import useState from the React library.
5. Create a new piece of state called typedLocation and a state setter function. Initialize it as an empty string.
6. Update the <input> value as typedLocation. Update the onChange event handler to set typedLocation to the current value of <input> using e.target.value.
7. Create a handleSubmit function that does the following:
   • Accept the event as a parameter
   • Prevent the default form behavior using e.preventDefault().
   • Call setLocation and pass it the current value of typedLocation.
   • Reset typedLocation to an empty string using the state setter function.
8. In the <form> opening tag, create an onSubmit event handler and pass it the handleSubmit function.
9. Try out the form! It should work for any city in the array and should throw an error if you type a city that doesn't match.

In components/Location.js:

The user may submit a location that isn't in the array, we want to make sure that the program can handle this.

1. If the location is not found in the data array, render a message to the user like "Location not found" or something similar.
2. Try submitting an incorrect location to verify that your application can handle this input.

Part 4: useEffect and fetch

We want users to be able to search ANY location, not just some hard coded data. Luckily, there are many weather APIs we can hook up to our application! Explore the following APIs and decide which one works best for you:

• Open Metro - No API Key required, buy you will need to figure out how to convert locations into coordinates.
• AccuWeather - API Key required. Make sure to use a .env and the dotenv package to read environment variables.
• Any other free weather API you can find. Here's a full list of free weather APIs

This is fairly open ended based on the API you select, but a few things to consider trying.

1. Select a Weather API from the options above. Explore the documentation for how to access the endpoint and the structure of the data that is returned.
2. Update the Location component with a call that initiates a fetch call to your endpoint(s) every time the location state is updated.
   • NOTE: You can add a variable to your dependency array for useEffect so that it runs only when that variable is updated.

   useEffect(() => {
       // DO SOMETHING
   }, [updatedVariable]) // useEffect only runs when updatedVariable changes.

3. Most of the APIs will require you to either provide coordinate points and/or city IDs in order to Based on the user input, render a 1 day, 5 day, or 10 day forecast.
4. Allow the user to specify if they want different information like Celsius vs. Fahrenheit or the amount of precipitation. Customize the outputs to respond to these inputs.