Segment: Send Track Event

 
export default async function main(args) {
let { writeKey, userId, event, properties } = args.inputVars; // Input variables

  // Check if the user has inputted the required variables
  if (!writeKey || !userId || !event) {
    return {
      // Returns the error path so we can continue the design
      next: { path: 'error' },
      // Renders a debug message in Voiceflow
      trace: [{ type: "debug", payload: { message: "Missing required input variables for this function" } }]
    };
  }

  function base64Encode(str) {
    const charSet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
    let output = '';
 
    for (let i = 0; i < str.length; i += 3) {
      const byte1 = str.charCodeAt(i) & 0xFF;
      const byte2 = i + 1 < str.length ? str.charCodeAt(i + 1) & 0xFF : 0;
      const byte3 = i + 2 < str.length ? str.charCodeAt(i + 2) & 0xFF : 0;
 
      const enc1 = byte1 >> 2;
      const enc2 = ((byte1 & 0x3) << 4) | (byte2 >> 4);
      const enc3 = ((byte2 & 0xF) << 2) | (byte3 >> 6);
      const enc4 = byte3 & 0x3F;
 
      if (isNaN(byte2)) {
        output += charSet.charAt(enc1) + charSet.charAt(enc2) + '==';
      } else if (isNaN(byte3)) {
        output += charSet.charAt(enc1) + charSet.charAt(enc2) + charSet.charAt(enc3) + '=';
      } else {
        output += charSet.charAt(enc1) + charSet.charAt(enc2) + charSet.charAt(enc3) + charSet.charAt(enc4);
      }
    }
 
    return output;
  }
  
  
  // Base URL for sending data to Segment
  const url = 'https://api.segment.io/v1/track';

  // Create the data payload
  const payload = {
    userId: userId,
    event: event,
    properties: properties
  };

  // Setup the request options, including headers
  const config = {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'Authorization': `Basic ${base64Encode(writeKey + ':')}`
    },
    body: JSON.stringify(payload)
  };

  // This is where we made the fetch request, we use try-catch for error handling
  try {
    // Make the fetch request
    const response = await fetch(url, config);

    // Check if the response status is OK (status in the range 200-299)
    if (!response.ok) {
      // If not OK, throw an error to be caught by the catch block
      throw new Error(`HTTP error! status: ${response.status}`);
    }

    // Parse the response
    const responseBody = await response.json;

    // Create the return objects if this is successful
    return {
      // Map the success path so we can continue in our flow
      next: { path: 'success' },
      // Optionally, return the response body if needed
      outputVars: {
        response: JSON.stringify(responseBody)
      }
    };
  }
  // Catches all the errors we threw and displays the debug message
  catch (error) {
    return {
      // Maps the error path so we can continue in our design
      next: { path: 'error' },
      // Renders a debug message in Voiceflow with the error
      trace: [{ type: "debug", payload: { message: "Error:" + error.message + ' ' + url } }]
    };
  }
}