Text to Speech in JavaScript using GitHub API

Aug 17, 2023

Categories:

javascript

texttospeech

github

Introduction

Text to speech refers to the technology that converts written text into spoken words. It allows users to listen to the content instead of reading it, providing accessibility and convenience. In web applications, text to speech can be particularly useful for users with visual impairments or reading difficulties, as well as for situations where hands-free operation is required.

For our project, we will be using the GitHub API to fetch text from a GitHub repository and convert it to speech. The GitHub API provides a convenient way to access and retrieve content from GitHub repositories programmatically. By integrating text to speech functionality with the GitHub API, we can create web applications that can read out the content of GitHub repositories, making it easier for users to consume textual information.

Prerequisites

Before diving into the project, there are a few prerequisites that you should have:

Basic understanding of JavaScript: JavaScript is the programming language we will be using to interact with the GitHub API and implement the text-to-speech functionality. It's important to be familiar with JavaScript concepts such as variables, functions, and API calls.
Familiarity with GitHub API: The GitHub API allows us to interact with GitHub repositories and fetch data such as text files. Understanding how to make API requests, handle responses, and authenticate with the GitHub API will be crucial for the project.
Text-to-speech technology knowledge: It's beneficial to have some knowledge of text-to-speech technology and the available options in JavaScript. While we will be using the Web Speech API in this project, understanding the basics of how text can be converted to speech programmatically will help you customize and enhance the functionality as needed.

By having a grasp of these prerequisites, you will be better equipped to follow along with the implementation and make necessary modifications to suit your requirements.

Setting up the project

To start working on the Text to Speech project using GitHub API, follow these steps:

Create a new GitHub repository: Go to GitHub and create a new repository for your project. Give it a meaningful name that reflects the purpose of your application.
Clone the repository to your local machine: Once you have created the repository, clone it to your local machine using the command line or a Git client of your choice. This will create a local copy of the repository that you can work on.
```
git clone https://github.com/your-username/your-repo.git
```
Initialize a new JavaScript project: Inside the cloned repository folder, initialize a new JavaScript project using a package manager like npm or yarn. This will create a package.json file that will track the dependencies and configuration of your project.
```
npm init -y
```
Set up necessary dependencies and libraries: To work with the GitHub API and implement text-to-speech functionality, you'll need to install the required dependencies and libraries. Some common libraries for working with APIs include axios, fetch, or jQuery. For text-to-speech, you can use the Web Speech API or other third-party libraries.
```
npm install axios
```
You can also include any other libraries or frameworks you might need for your specific project.

Now that your project is set up, you can move on to the next steps of authenticating with the GitHub API and fetching the desired text from a GitHub repository.

Authenticating with GitHub API

To access the GitHub API, you need to authenticate your application. This involves registering a new OAuth application on GitHub, obtaining a client ID and client secret, and generating an access token.

To register a new OAuth application on GitHub, follow these steps:

Go to your GitHub account settings.
Navigate to the "Developer settings" tab.
Click on "OAuth Apps" in the left sidebar.
Click on the "New OAuth App" button.
Fill in the required information, such as the "Application name," "Homepage URL," and "Authorization callback URL." The "Homepage URL" can be any valid URL, and the "Authorization callback URL" should be the URL where GitHub will redirect the user after they authorize your application.
Click on the "Register application" button.

After registering the OAuth application, you will be provided with a client ID and client secret. These credentials are necessary for generating an access token.

To generate an access token, follow these steps:

Make a POST request to the GitHub API's "oauth/token" endpoint with your client ID, client secret, and other required parameters. The request should include the following parameters:
- client_id: The client ID obtained during the OAuth application registration.
- client_secret: The client secret obtained during the OAuth application registration.
- code: The authorization code obtained after the user authorizes your application.
- redirect_uri: The same "Authorization callback URL" specified during the OAuth application registration.
- grant_type: The value should be "authorization_code".
The response from the API will contain an access token. This token is required to make authenticated requests to the GitHub API on behalf of the user.

It's important to note that the access token should be kept securely and not exposed to the public.

Fetching text from a GitHub repository

To fetch text from a GitHub repository, we need to authenticate with the GitHub API using the access token. This token will allow us to access the repository and retrieve the desired text file.

First, we need to write a function that authenticates with the GitHub API using the access token. This function will make use of the GitHub API's authentication mechanism to ensure that we have the necessary permissions to access the repository.

Once authenticated, we can use the GitHub API's GET /repos/{owner}/{repo}/contents/{path} endpoint to fetch the desired text file from the repository. The {owner} parameter refers to the owner of the repository, {repo} refers to the repository name, and {path} refers to the path to the text file within the repository.

After fetching the text file, we can extract and process the text data as needed. This may involve parsing the file contents, removing any unwanted characters or formatting, and preparing the text for conversion to speech.

By following these steps, we can successfully fetch the desired text from a GitHub repository and prepare it for conversion to speech.

Converting text to speech

In our project, we will be using the Web Speech API for converting the fetched text to speech. The Web Speech API is a JavaScript API that provides speech recognition and synthesis capabilities in web applications.

To implement the text-to-speech functionality, we can use the SpeechSynthesisUtterance object provided by the Web Speech API. This object represents a speech request, and we can customize it by setting properties such as the text to be spoken, voice, volume, pitch, and rate.

Here is an example of how we can convert the fetched text to speech using the Web Speech API:

function convertTextToSpeech(text) {
  const utterance = new SpeechSynthesisUtterance(text);
  
  // Set the voice
  const voices = window.speechSynthesis.getVoices();
  utterance.voice = voices.find(voice => voice.name === 'Google US English');
  
  // Set other parameters
  utterance.volume = 1; // 0 to 1
  utterance.pitch = 1; // 0 to 2
  utterance.rate = 1; // 0.1 to 10
  
  // Speak the text
  window.speechSynthesis.speak(utterance);
}

In this example, we create a new SpeechSynthesisUtterance object with the fetched text as the input. We then set the voice to be used for speech synthesis by searching for a specific voice name. Additionally, we can adjust the volume, pitch, and rate of the speech as per our requirements. Finally, we use the speak method of the speechSynthesis object to convert the text to speech.

By customizing the voice, speed, and other parameters, we can create a more personalized and engaging text-to-speech experience for our users.

Building the web application

To build the web application, we need to focus on designing a simple user interface, integrating the text-to-speech function, and adding event handlers for user interactions and playback controls.

First, let's design a user interface that will display the fetched text and provide playback controls. This can be done using HTML and CSS. You can create a container element to display the text and add buttons for play, pause, and stop controls. You can also include a slider to control the speed of the speech if desired.

Next, we need to integrate the text-to-speech function into our application. Depending on the technology you chose, this step may involve using the Web Speech API or another text-to-speech library. You'll need to call the appropriate function to convert the fetched text into speech and pass in any desired parameters such as voice, speed, and volume.

Finally, we need to add event handlers for user interactions and playback controls. This can be done using JavaScript. You can add event listeners to the play, pause, and stop buttons to trigger the corresponding actions. Additionally, you can listen for changes in the slider value to adjust the speed of the speech in real-time.

By following these steps, you can build a web application that retrieves text from a GitHub repository, converts it to speech, and provides playback controls for the user. Remember to test the application on different browsers and devices to ensure compatibility and troubleshoot any issues that may arise.

Testing and troubleshooting

Once you have built your web application for text to speech using the GitHub API, it is important to thoroughly test it to ensure it works correctly on different browsers and devices. Here are some steps you can follow for testing and troubleshooting:

Test the web application on different browsers: Ensure that the application works as expected on popular browsers such as Chrome, Firefox, Safari, and Edge. Pay special attention to any browser-specific issues or differences in behavior.
Test the web application on different devices: Verify that the application functions properly on various devices, including desktops, laptops, tablets, and mobile phones. Test it on both iOS and Android devices to ensure cross-platform compatibility.
Identify and troubleshoot issues or errors: During testing, carefully observe the application's behavior and functionality. If you encounter any issues or errors, make note of them and try to identify the root cause. Common issues could include incorrect rendering of text, audio playback problems, or unexpected errors.
Use browser developer tools for debugging: Most modern browsers provide developer tools that can be used for debugging web applications. These tools allow you to inspect the application's HTML, CSS, and JavaScript, as well as monitor network requests and debug JavaScript code. Utilize these tools to track down and fix any issues you encounter.

By thoroughly testing your web application and troubleshooting any issues that arise, you can ensure a smooth and reliable user experience. Remember to iterate and test your application regularly, especially when making changes or adding new features.

Conclusion

In this article, we have explored how to implement text to speech in JavaScript using the GitHub API. We started by setting up the project and authenticating with the GitHub API. Next, we fetched text from a GitHub repository and converted it to speech using the Web Speech API.

Text to speech is an important feature in web applications as it enhances accessibility and user experience. It allows users with visual impairments to consume textual content. It can also be used to provide audio feedback or narration in interactive applications.

Future improvements to this project could include adding support for multiple languages and voices, implementing advanced speech synthesis techniques like prosody control, and integrating with other text-to-speech APIs for more robust functionality.

By following the steps outlined in this article, you should be able to integrate text to speech capabilities into your JavaScript projects using the GitHub API. Happy coding!

References

Here are some external resources and documentation that were used in the blog post: