how do POST request in puppeteer?

Getting the "order" right can be a bit of a challenge. Documentation doesn't have that many examples... there are some juicy items in the repository in the example folder that you should definitely take a look at.

https://github.com/GoogleChrome/puppeteer/tree/master/examples

Here is the example; place the following into an async block:

    // Create browser instance, and give it a first tab    const browser = await puppeteer.launch();    const page = await browser.newPage();    // Allows you to intercept a request; must appear before    // your first page.goto()    await page.setRequestInterception(true);    // Request intercept handler... will be triggered with     // each page.goto() statement    page.on('request', interceptedRequest => {        // Here, is where you change the request method and         // add your post data        var data = {            'method': 'POST',            'postData': 'paramFoo=valueBar&paramThis=valueThat'        };        // Request modified... finish sending!         interceptedRequest.continue(data);    });    // Navigate, trigger the intercept, and resolve the response    const response = await page.goto('https://www.example.com/search');         const responseBody = await response.text();    console.log(responseBody);    // Close the browser - done!     await browser.close();

Here the complete example with Puppeteer 2.0.0 :

    const puppeteer = require("puppeteer");    const devices = require("puppeteer/DeviceDescriptors");    async function main() {      const browser = await puppeteer.launch({        args: ["--enable-features=NetworkService", "--no-sandbox"],        ignoreHTTPSErrors: true      });      const page = await browser.newPage();      await page.setRequestInterception(true);      page.once("request", interceptedRequest => {        interceptedRequest.continue({          method: "POST",          postData: "foo=FOO&bar=BAR",          headers: {            ...interceptedRequest.headers(),            "Content-Type": "application/x-www-form-urlencoded"          }        });      });      const response = await page.goto("https://postman-echo.com/post");      console.log({        url: response.url(),        statusCode: response.status(),        body: await response.text()      });      await browser.close();    }    main();

Note that if you check response.request().method() it won't be updated (still GET)

There's a quirk with the way setRequestInterception and the 'request' event work. Once activated, Puppeteer will send the POST data to every resource on the page, not just the original requested page. I was having the issue that all of my page resources (scripts, CSS) were failing to load once I added POST data in Puppeteer.

Since I only want to apply POST data to the first request, this code worked for me:

// Used for serializing POST parameters from an objectconst querystring = require('querystring');// ...const browser = await puppeteer.launch();const page = await browser.newPage();let postData = {a: 1, b: 2};await page.setRequestInterception(true);page.once('request', request => {    var data = {        'method': 'POST',        'postData': querystring.stringify(postData),        'headers': {            ...request.headers(),            'Content-Type': 'application/x-www-form-urlencoded'        },    };    request.continue(data);    // Immediately disable setRequestInterception, or all other requests will hang    page.setRequestInterception(false);});const response = await page.goto('https://www.example.com/');