Debugging SSR Synchronization Issues

Present a method for identifying and resolving mismatches between server-rendered and client-side hydrated content.

if (typeof window === 'undefined') {
  // Server-specific logic
} else {
  // Client-specific logic
}

This code segment checks the environment in which the code is running (server or client) by verifying if 'window' is defined, allowing for separating SSR and client-side logic to avoid hydration mismatches.

console.log('Server-rendered content:', document.body.innerHTML);
window.addEventListener('load', () => {
  console.log('Client-rendered content:', document.body.innerHTML);
});

Logs the content rendered by the server and compares it with the client-rendered content after the page fully loads. Useful for identifying discrepancies in SSR and CSR outputs.

window.addEventListener('DOMContentLoaded', () => {
  // Fetch initial state from server-rendered global variable
  const initialState = window.__INITIAL_STATE__;
  console.log('Initial State:', initialState);
  // Proceed with client-side hydration using initialState
});

Uses an event listener to wait for the DOM to be fully loaded, then retrieves the server-rendered initial state from a global variable. This process ensures that client-side scripts utilize the same initial state as the server, aiding in synchronization between SSR and CSR.