v0 and Fitbit API integration: Step-by-Step Guide 2025

 

Setting Up Dependencies

 

• Create or open the package.json file in your project’s root directory.
• Add the dependency for axios. Since your v0 project does not allow terminal installation, insert the dependency manually:

  
  {
    "dependencies": {
      "axios": "^0.27.2"
      // Add other dependencies if needed
    }
  }
      

• When you deploy or build your project, ensure your environment picks up the dependencies listed in your package.json.

 

Creating the Fitbit Integration File

 

• Create a new file named fitbit.ts in your project’s source directory.
• Insert the following TypeScript code into fitbit.ts. This code includes functions to redirect the user to Fitbit’s OAuth2 page, exchange the received authorization code for an access token, and fetch user profile data:

import axios from 'axios';

const clientId = "YOURCLIENTID_HERE";
const redirectUri = "YOURREDIRECTURI_HERE";
const clientSecret = "YOURCLIENTSECRET_HERE"; // For security, ensure proper handling in production
const authUrl = "https://www.fitbit.com/oauth2/authorize";
const tokenUrl = "https://api.fitbit.com/oauth2/token";
const scope = "activity profile settings sleep";
const responseType = "code";
// Function to redirect the user to Fitbit’s OAuth2 authorization page
export function redirectToFitbitAuth(): void {
  const url = ${authUrl}?response_type=${responseType}&client_id=${clientId}&redirect_uri=${encodeURIComponent(redirectUri)}&scope=${encodeURIComponent(scope)};
  window.location.href = url;
}
// Function to exchange the authorization code for an access token
export async function exchangeCodeForToken(code: string): Promise {
  const params = new URLSearchParams();
  params.append('client_id', clientId);
  params.append('granttype', 'authorizationcode');
  params.append('redirect_uri', redirectUri);
  params.append('code', code);
  const authHeader = btoa(${clientId}:${clientSecret});
  try {
    const response = await axios.post(tokenUrl, params, {
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
        'Authorization': Basic ${authHeader}
      }
    });
    return response.data;
  } catch (error) {
    console.error("Error exchanging code for token:", error);
    throw error;
  }
}
// Function to fetch user profile data from Fitbit using the access token
export async function fetchFitbitProfile(accessToken: string): Promise {
  try {
    const response = await axios.get('https://api.fitbit.com/1/user/-/profile.json', {
      headers: {
        'Authorization': Bearer ${accessToken}
      }
    });
    return response.data;
  } catch (error) {
    console.error("Error fetching Fitbit profile:", error);
    throw error;
  }
}
  

 

Integrating Fitbit Functions Into Your Main Code

 

• Open your main TypeScript file (for example main.ts or app.ts).
• Import the Fitbit functions from fitbit.ts:

  
  import { redirectToFitbitAuth, exchangeCodeForToken, fetchFitbitProfile } from "./fitbit";
      

• Add an event listener to a login button that will initiate the Fitbit OAuth flow. Insert the following code snippet where you initialize your UI interactions:

  
  const loginButton = document.getElementById("fitbit-login-button");
  if (loginButton) {
    loginButton.addEventListener("click", () => {
      redirectToFitbitAuth();
    });
  }
      

• Handle the callback after redirection. Add this code snippet to check for the authorization code in the URL and exchange it for an access token:

  
  window.addEventListener("load", async () => {
    const params = new URLSearchParams(window.location.search);
    const code = params.get("code");
    if (code) {
      try {
        const tokenData = await exchangeCodeForToken(code);
        console.log("Token Data:", tokenData);
        const profile = await fetchFitbitProfile(tokenData.access_token);
        console.log("Fitbit Profile:", profile);
        // Further processing can be done with the profile data
      } catch (error) {
        console.error("Error during Fitbit API integration:", error);
      }
    }
  });
      

 

Updating Your HTML

 

• Edit your HTML file to include a button that users can click to connect with Fitbit. Insert the following snippet in the appropriate location:

  
  Login with Fitbit
      

 

Final Notes

 

• Replace YOURCLIENTIDHERE, YOURCLIENTSECRETHERE, and YOURREDIRECTURI_HERE with the actual values provided by Fitbit when you register your application.
• Ensure that the redirect URI specified in your code matches the one configured in your Fitbit application settings.
• Review security practices for handling sensitive data, especially the client secret. In production, you should not expose your client secret in client-side code.
• After making these changes, save all files and deploy your project to see the integration in action.