---
url: https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/
title: "SSR.js\n                #"
description: "This document describes the SSR class, which is responsible for rendering and caching server side rendered (SSR) pages using Puppeteer. The class manages the re"
lang: uk
updated: 2026-09-12T02:31:04.446Z
---

# SSR.js [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#ssr-js)

## Overview [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#overview)

This document describes the SSR class, which is responsible for rendering and caching server-side rendered (SSR) pages using Puppeteer. The class manages the rendering process, including logging, bundling, and caching of HTML and JSON data.

## Content [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#content)

## Methods [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#methods)

### `generate` [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#generate)

-   **Purpose**: Renders an SSR page using Puppeteer, processes the output, and caches the result.
    
-   **Parameters**:
    
    -   **root** (string): Root directory of the website.
        
    -   **website** (string): Website identifier for caching and resource management.
        
    -   **route** (object): Contains route-specific information like path and query parameters.
        
    -   **chapters** (object): Site-specific chapters data.
        
    -   **auth\_key** (string): Authorization key for accessing gudhub resources.
        
    -   **buildFolder** (string): Path to the website folder containing built files.
        
    -   **disableImagesRegeneration** (boolean): If true, prevents regeneration of images.
        
    -   **preview** (boolean): Indicates whether the rendering is for preview purposes.
        
    -   **disableBundling** (boolean): If true, skips bundling of components.
        
    -   **config** (object): Configuration data for SSR.
        
    -   **gudhubDBSettingsConfig** (object): configurations of gudhub instance used to get data.
        
    -   **clientSortedAndFilteredQueryParams** (string, optional): Pre-sorted query parameters to pass them in puppeteer.
        
    -   **enableSSRClientSideLogging** (boolean): enables SSR error logging from puppeteer in the browser console and displays broken components along with their errors. Controlled via the `enable-ssr-logging` and `mode=ssr` URL parameters:
        
        -   `?enable-ssr-logging=true&mode=ssr` → Enables logging
        -   `?enable-ssr-logging=false&mode=ssr` → Disables logging
        
        Defaults to `true` in development mode.
        
-   **Returns**: The HTML content of the rendered page. '404' if the page is not found. Error object if SSR fails.
    
-   **Behavior**: Launches a Puppeteer page and sets up logging. Injects client configuration and language-specific data. Loads the page and processes the resulting HTML and assets. Bundles components if not disabled. Caches HTML and JSON data unless in preview mode.
    

### `cacheHTML` [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#cachehtml)

-   **Purpose**: Caches the rendered HTML content of an SSR page.
    
-   **Parameters**:
    
    -   `content` (string): The HTML content to be cached.
    -   `website` (string): Website identifier for caching.
    -   `route` (object): Contains route object.
    -   `formattedQueryString` (string, optional): if page needs to be cached by queryParams, pass formatted (filtered by website queryParams whitelist and sort by alphabet) query string to append to the cache path.
-   **Returns**: true upon successful caching.
    
-   **Behavior**: Constructs the cache path using the route and query parameters. Creates directories if they do not exist. Writes the HTML content to an index.html file in the cache directory.
    

### `cacheJsonData` [#](https://gudhub.com/uk/docs/ssr-ssg/server/features/ssr/#cachejsondata)

-   **Purpose**: Caches JSON data associated with an SSR page.
    
-   **Parameters**:
    
    -   `jsonData` (object): The JSON data to be cached.
    -   `website` (string): Website identifier for caching.
    -   `route` (object): Contains route-specific information like path and query parameters.
-   **Returns**: true upon successful caching, false otherwise.
    
-   **Behavior**: Constructs the cache path using the route and query parameters. Creates directories if they do not exist. Writes the JSON data to a cachedJsonData.json file in the cache directory.