Nightbot

A simple web scraping library using Nightmare which is one of the greatest headless browsing module.

Install

npm install --save nightbot

Usage

const nightbot = require("nightbot");

Examples

Get result as jsdom:

const nightbot = require("nightbot");

/**
 * program for nightmareJS:
 * @see https://github.com/segmentio/nightmare
 */
const program = [
  // Step to the target page:
  ["goto", "https://duckduckgo.com"],
  ["type", "#search_form_input_homepage", "github nightmare"],
  ["click", "#search_button_homepage"],
  ["wait", 2000],
];

// a selector of target you want to get:
const selector = "h2.result__title";

// Execute!
nightbot.execute({
  program,
  selector,
}, (err, elements) => {
  // you got the target as jsdom elements:
  console.log("elements[0].querySelector('b').innerHTML:", elements[0].querySelector("b").innerHTML);
});

Get result as jquery object:

...

nightbot.execute({
  program,
  selector,
  result: "jquery", // If set "jquery", returns a result as jquery object!
}, (err, jqResult) => {
  // you got the target as jquery object:
  console.log("jqResult.length:", jqResult.length);
  console.log("jqResult.eq(0).html():", jqResult.eq(0).html());
});

async/await also available:

...

async function run() {
  console.log("async/await executing ...");
  // Execute!
  const elements = await nightbot.execute({
    program,
    selector,
  });
  console.log("async/await result ***************");
  console.log("elements[0].querySelector('b').innerHTML:", elements[0].querySelector("b").innerHTML);
}

run().catch((err) => {
  console.log("result error:", err);
});

Reuses the same nightmare instance to make the browser open process faster on loop exection:

...

const ite = function*() {
  for (let len = 2, i = 0; i < len; i++) {
    // Execute!
    yield nightbot.execute({
      program,
      selector,
      nightmareOptions,
      newInstance: false,
      keepInstance: true, // NOTE: reuses the same instance
    }, (err, elements) => {
      console.log(`[${i}] callback result ***************`);
      if (err) return console.log("err:", err);
      console.log(`[${i}] elements[0].querySelector('b').innerHTML:`, elements[0].querySelector("b").innerHTML);
      ite.next();
    });
  }
  // finish!
  nightbot.end((err) => {
    console.log("finished!");
  });
}();
ite.next(); // fire!

async/await also available:

...

async function run() {
  console.log("async/await executing ...");
  for (let len = 2, i = 0; i < len; i++) {
    // Execute!
    const elements = await nightbot.execute({
      program,
      selector,
      nightmareOptions,
      newInstance: false,
      keepInstance: true, // NOTE: reuses the same instance
    });
    console.log(`[${i}] async/await result ***************`);
    console.log(`[${i}] elements[0].querySelector('b').innerHTML:`, elements[0].querySelector("b").innerHTML);
  }
  // finish!
  await nightbot.end();
  console.log("finished!");
}

run().catch((err) => {
  console.log("result error:", err);
});

More examples? Please check examples.

Authors

• Akira Tanaka - Founder - akirattii@github

LICENSE

This project is licensed under the MIT License - see the LICENSE.txt file for details

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