What is @smithy/middleware-content-length?
@smithy/middleware-content-length is a middleware package for the Smithy client framework. It is used to automatically calculate and set the Content-Length header for HTTP requests. This is particularly useful when dealing with payloads where the size needs to be explicitly defined.
What are @smithy/middleware-content-length's main functionalities?
Automatic Content-Length Calculation
This feature automatically calculates the Content-Length of the request body and sets it in the HTTP headers. This is useful for ensuring that the server knows the size of the incoming request payload.
const { ContentLengthMiddleware } = require('@smithy/middleware-content-length');
const { HttpRequest } = require('@smithy/protocol-http');
const request = new HttpRequest({
hostname: 'example.com',
method: 'POST',
body: JSON.stringify({ key: 'value' })
});
const middleware = ContentLengthMiddleware();
const handler = middleware((next) => async (args) => {
return next(args);
});
handler({ request }).then((response) => {
console.log(response.request.headers['Content-Length']); // Outputs the calculated Content-Length
});
Other packages similar to @smithy/middleware-content-length
axios
Axios is a popular HTTP client for Node.js and the browser. It automatically sets the Content-Length header for POST requests with a body. However, it is a full-fledged HTTP client and not just middleware.
request
The request package is another HTTP client for Node.js that automatically handles the Content-Length header for requests with a body. Like axios, it is a complete HTTP client and not just middleware.
node-fetch
Node-fetch is a lightweight module that brings window.fetch to Node.js. It also automatically sets the Content-Length header for requests with a body. It is more lightweight compared to axios and request.