HTTP/2 is a major revision of the HTTP protocol that improves web performance by introducing new features such as server push, binary framing, and header compression. One of the most exciting features of HTTP/2 is server push, which allows servers to proactively send resources to clients before they request them.
In this article, we will explore how Node.js can take advantage of server push in HTTP/2 to improve website performance.
How Server Push Works
In HTTP/1.x, each resource on a webpage must be requested individually, which can lead to slow load times and increase latency. With HTTP/2, server push allows the server to send additional resources to the client before they are requested. This means that the client can receive all of the resources it needs to render the page faster and more efficiently.
Server push works by allowing the server to send additional resources along with the main HTML file in response to a single request. For example, if the client requests an HTML file, the server can also send images, stylesheets, and javascript files in the same response. The server provides hints to the client about which resources should be pushed based on the structure of the HTML document.
Using HTTP/2 Server Push with Node.js
Node.js has excellent support for HTTP/2 and can take advantage of the server push feature. To use server push, we need to create an HTTP/2 server and then add code to push resources to the client.
Here's an example of how to create an HTTP/2 server in Node.js:
-- -------------------- ---- -------
----- ----- - -----------------
----- -- - --------------
----- ------- - -
---- ------------------------------
----- -----------------------------
--
----- ------ - --------------------------------- ----- ---- -- -
----- ------ - -----------
----- --------- - -------------- --------------
-- -------- --- ---- -
---------------------------- ---------------- ----------------------------
--------------------------- --------------
------------------ -------------------------------------------
-- ---- ----- -- --- ------
------------------------ -- -
----- -------- - --------- - -----
----- ---------- - ------------------------------
--------------------------- ------ ----- ----------- -- -
-- ----- ----- ----
----------------------------
---
---
----------
- ---- -
-------------------
----------
-
---
--------------------In this example, we're creating an HTTP/2 server and serving an HTML file with some CSS and JavaScript resources. We're also pushing two additional resources to the client using the stream.pushStream() method.
When a client requests the main HTML file, the server sends the HTML file along with the CSS and JavaScript files in the same response. The server also provides hints to the client to request the CSS and JavaScript files from its cache for subsequent loads.
By pushing resources to the client ahead of time, we can improve website performance and reduce latency.
Conclusion
HTTP/2 server push is a powerful feature that can significantly improve website performance. With Node.js, we can easily take advantage of this feature by creating an HTTP/2 server and pushing resources to the client.
By leveraging HTTP/2 server push in our applications, we can provide a faster and more efficient user experience for our users.
来源：JavaScript中文网 ，转载请注明来源 https://www.javascriptcn.com/post/29116