Setup firebase with firestore data in NextJS

Install Required Packages

npm install firebase @radix-ui/react-popover react-quill lucide-react date-fns framer-motion

Set up Firebase

Create a file called firebase.js in a folder called lib in the root of your project and add your Firebase configuration:

import { initializeApp } from "firebase/app";
import { getFirestore } from "firebase/firestore";
 
const firebaseConfig = {
  apiKey: "your-api-key",
  authDomain: "your-auth-domain",
  projectId: "your-project-id",
  storageBucket: "your-storage-bucket",
  messagingSenderId: "your-messaging-sender-id",
  appId: "your-app-id",
};
 
const app = initializeApp(firebaseConfig);
const db = getFirestore(app);
 
export { db };

Create the Component

Create a new component called NewItem.tsx in the components folder:

"use client";
import React, { useState } from "react";
import { addDoc, collection, serverTimestamp } from "firebase/firestore";
import {
  Popover,
  PopoverContent,
  PopoverTrigger,
} from "@radix-ui/react-popover";
import { format } from "date-fns";
import { motion } from "framer-motion";
import { db } from "@/lib/firebase";
 
interface NewItemProps {
  content?: string;
}
 
export function NewItem({ content }: NewItemProps) {
  const [open, setOpen] = useState(false);
  const [title, setTitle] = useState("");
  const [date, setDate] = useState<Date | null>(null);
  const [description, setDescription] = useState("");
  const [label, setLabel] = useState("");
  const [items, setItems] = useState<Item[]>([]);
  const [loading, setLoading] = useState(false);
  const [markdownContent, setMarkdownContent] = useState("");
 
  useEffect(() => {
    const unsubscribe = auth.onAuthStateChanged((user) => {
      if (user) {
        console.log("user", user);
      }
      setLoading(false);
    });
    return (): void => unsubscribe();
  }, []);
 
  const handleSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
    e.preventDefault();
 
    try {
      const newItem: Item = {
        title,
        userId: user.uid,
        description: markdownContent,
        createdAt: serverTimestamp(),
        id: "",
        subject,
        selectedDate: date,
        label,
      };
 
      const docRef = await addDoc(collection(db, "items"), newItem);
      newItem.id = docRef.id;
 
      setItems((prevItems: Item[]) => [newItem, ...prevItems]);
      setDescription("");
      setTitle("");
      setDate(null);
      setSubject("");
      setLabel("");
      setMarkdownContent("");
      toast({
        title: "Item created successfully.",
        description: `with title ${title}`,
      });
    } catch (error) {
      toast({
        title: "Something went wrong.",
        description: `Your request failed. Please try again. ${error}`,
        variant: "destructive",
      });
      console.error(error);
    } finally {
      setOpen(false);
    }
  };
 
  // Render form and other JSX here...
 
  return <>{/* Render Drawer and other JSX here... */}</>;
}

In this component:

We have used the useState hook to manage the local state for title, date, description, label, and items.
The handleSubmit function is used to post the data to Firestore. It creates a new item object, posts it to Firestore, and then adds it to the local state.
The Popover component from @radix-ui/react-popover is used to create a dropdown for selecting a date and a label.
The ReactQuill component is used for the description input field to allow markdown input.
The Drawer component from vaul is used to toggle the visibility of the form.

Fetching the Data

To fetch the data from Firestore and display it, you can create a separate component or use the useEffect hook in the NewItem component or another parent component.

In the useEffect hook, you can use the onSnapshot function from firebase/firestore to listen for real-time updates from Firestore and update the local state accordingly.

useEffect(() => {
  const unsubscribe = onSnapshot(collection(db, "items"), (snapshot) => {
    const fetchedItems: Item[] = [];
    snapshot.forEach((doc) => {
      const item = doc.data() as Item;
      item.id = doc.id;
      fetchedItems.push(item);
    });
    setItems(fetchedItems);
  });
  return (): void => unsubscribe();
}, []);

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