I think i am making some kind of confusion here.
According to the documentation, if i want Server Side Rendering (SSR) for the page i export the async function:
getServerSideProps
But if i do that i can't build the project for running either locally or now Zeit now.
If i try build or deploy i get:
Error for page /_error: pages with getServerSideProps can not be exported. See more info here: https://err.sh/next.js/gssp-export
The link provided by the error says i can't export. But I used the example from the documentation below:
import React from "react"
export async function getServerSideProps() {
return { props: { } }
}
function Page({ data }) {
// Render data...
}
export default Page
Do i have to change some configuration somewhere?
How to prevent from building this static page?
getStaticProps() is the way to go under the following conditions:
The data required to render the page is available at build time ahead of a user’s request
The data comes from a headless CMS
The data can be publicly cached (not user-specific)
The page must be pre-rendered (for SEO) and be very fast — getStaticProps generates HTML and JSON files, both of which can be cached by a CDN for performance
Refer here for when to use getStaticProps vs getServerSideProps
https://nextjs.org/docs/basic-features/data-fetching/get-static-props
vs:
https://nextjs.org/docs/basic-features/data-fetching/get-server-side-props
Won´t work on page _error.js, by design decision, as posted here by nextjs maintenance staff.
One possibility is to use getInitialProps, instead.
Related
i have an ssr quasar app , when i lunch the website for the first time in chrome developer mode i see that the server return an html document.
but when i navigate to another page the server return only js scripts soo not rendering at the server side , it behave like a spa after the first page,
Is there any parameters i can change to render all the page at the server side ?
i read all the documentation regarding quasar ssr mode but couldn't find anything
and here is how the ssr config object looks like inside quasar.config.js
ssr: {
pwa: false,
prodPort: 3000, //
middlewares: [
'render', // keep this as last one
],
},
This is by design. Quasar is VueJS based, which (unlike e.g. PHP) focuses on delivering pages basically as SPAs, i.e. giving you data + JS to render it.
SSR only means that the first page is rendered on the server (e.g. for SEO purposes) and javascript takes over for fetching and rendering all subsequently loaded pages (or better the data + a recipe to render them) on the client. Thus, SSR will only get you server-side rendered pages upon initial load or page reload, all other renders are client-side.
You may learn about SSR, but also SSG (Static Site Generation), that might fit your needs, here: https://vuejs.org/guide/scaling-up/ssr.html
In a Next.JS app, you see that the code for a component runs on both the Server and the Client.
So if you have the following code:
const Title = () => {
console.log('--> Hello')
return (<h1>Some title</h1>)
}
and you run this in a dev environment (npm run dev), you will see the console.log statement print to both the Server in the terminal as well as the Browser's console.
So firstly, what is happening here? How come all the code on the page gets run in both places on every page load?
Wouldn't Next.JS just sent a pre-transpiled HTML file to the Browser? How come that console.log statement is getting run in the Server even though we're not in getServerSideProps or something similar?
Now, this may be a core feature of React that I've overlooked, so please tell me if it's just that manifesting in Next.JS
Wouldn't Next.JS just sent a pre-transpiled HTML file to the Browser?
Yes, this is correct. But to transpile it to html it first needs to run your app and render it with ReactDOMServer.renderToString method.
So it is not specifically Next.js feature, but just a React SSR thing, every similar framework would do the same thing.
I recently started working with Svelte via SvelteKit and I have a few questions about this framework to which I haven't been able to find any direct answers in the source/documentation:
SvelteKit has SSR and in the documentation it says:
All server-side code, including endpoints, has access to fetch in case you need to request data from external APIs.
What code is server-side rendered besides endpoints and how it decides this? All the code from scripts from svelte pages runs on the client or some of it runs on the server?
In order to make use of SSR locally you need an adapter for it or does svelte start a server on its own?
How does SSR work in a production environment like Netlify for example. Is the netlify adapter is used for SSR (running the endpoints in a netlify function)? If a netlify adapter is not provided, how/where would the endpoints run?
If I want to use custom netlify functions in a sveltekit project what configurations are needed (besides netlify.toml and netlify adapter) in order for netlify to recognize the functions from inside the functions directory?
What is the difference here between SSR and prerendering? SSR is used only for endpoints and other js code and prerendering is used for generating the Html to send it to the client which will then be hydrated, with the compiled js code, also sent to the browser?
Thanks!
By default, pages are also server-side rendered when you first visit a site. When you navigate to a subsequent pages they will be client-side rendered.
Adapters are only used in production. If you run npm run dev for local development you still get SSR. In production, how exactly SSR is run depends on the adapter you choose. An adapter is required for production. adapter-node runs SSR on a Node server, adapter-netlify runs SSR in Netlify functions, etc.
See here for discussion of custom Netlify functions: https://github.com/sveltejs/kit/issues/1249
SSR is used for pages as well, but prerendering means that rendering happens at build time instead of when a visitor visits the page. See this proposed documentation for more info: https://github.com/sveltejs/kit/pull/1525
Pages are SSR when you first visit the site, including all the code in the script tag of your svelte page. However, as you navigate to other pages, the code will be run on the client and the page will be dynamically rendered as Sveltekit makes a single page web app look like it has different pages with the history API.
You can decide which code runs on the server and which runs on the client. If you don't do anything special, Sveltekit and your deployment environment will decide that for you. If you want some code to run only in browser (perhaps it needs to use the window object or need authentication), you can use the browser variable.
import { browser } from '$app/environment';
if (browser) {
// Code that runs only in browser
}
You can also put the code in the onMount function, which will be run when the component first mounts, which only happens in browser.
import { onMount } from 'svelte';
onMount(() => {
// Do stuff
})
If you want SSR, you can put the function in the load function in route/+page.js. One typical use case is for a blog entry that grabs the content from the database and populates and formats the content. If you get to the page from a URL, or refresh page, the code in the load function will be executed on the server. If you navigate to the page from elsewhere in your web app, the code will be run on the client, but it will look like SSR as the UI will refresh only after the load function returns (you won't see loading screen or a blank page). See the official docs for more for more.
import { error } from '#sveltejs/kit';
/** #type {import('./$types').PageLoad} */
export function load({ params }) {
if (params.slug === 'hello-world') {
return {
title: 'Hello world!',
content: 'Welcome to our blog. Lorem ipsum dolor sit amet...'
};
}
throw error(404, 'Not found');
}
I am not very sure about how to use Netlify function, as Ben mentions, you can see the discussion on https://github.com/sveltejs/kit/issues/1249. Although I think that you might be able to implement the same functionality with +page.server.js, and the "Actions" to invoke them.
I've set a custom server from the example but, my question is...
Can the server code access the NextJs code?
I mean, NextJs is built with webpack, therefore packed in its own context, so if I want to initialize something (let's say, database, logging system, etc.) in the server before NextJs has started, and then access it from NextJs... is it possible? I don't see how unless server code and NextJs code are in the same bundle, is it?
Yes, I guess there are some hacks that can be used, like importing files in runtime with __non_webpack_require__... but that seems like a hack (?) and only in one direction.
Any other better option?
If you use SSR in NextJS, you can access to APIs before rendering.
https://nextjs.org/docs/basic-features/data-fetching/get-server-side-props
If you export a function called getServerSideProps (Server-Side Rendering) from a page, Next.js will pre-render this page on each request using the data returned by getServerSideProps.
It fetches your data upon a user requesting your website everytime.
Thatmeans no matter what you build first on your server. Next.js will fetch for it every time. The comment above me sent the correct link. https://nextjs.org/docs/basic-features/data-fetching/get-server-side-props
TO view all data fetching techniques from next.js visit: https://nextjs.org/docs/basic-features/data-fetching/overview
PLease comment back to this to see if this helped, or if we missunderstood the question, so that we can help solve this issue, or if you resolved it. happy coding!
I have a Meteor webapp. (e.g. http://www.merafi.com). I want to scrape the website using Google Apps Script. I wrote a small script for this.
function myFunction() {
const url = 'http://www.merafi.com';
const response = UrlFetchApp.fetch(url, {muteHttpExceptions: true});
return response.getContentText();
}
The script is used inside a Google Spreadsheet as a macro.
=myFunction()
The problem with scraping a Meteor webapp is that I get an empty body with only script tags within it. How do I get the content inside the body tag?
Some crawler like PhantomJS or NightmareJS is required to run the Meteor JS after the page is loaded. Unfortunately, Google Apps Script environment does not allow to load external dependencies / packages. The Apps Script API does not have any method which loads a page in a separate iframe / webview. This is not possible using Google Apps Script.
Thanks to #Floo and #CodeChimp for answering the question in comments.