Skip to content

gocrawlvsayakashi

BSD-3-Clause 6 2 2,037
58.1 thousand (month) Nov 20 2016 (3 years ago)
212 1 8 AGPL-3.0-only
Apr 18 2019 79 (month) 1.0.0-beta8.4(1 year, 5 months ago)

Gocrawl is a polite, slim and concurrent web crawler library written in Go. It is designed to be simple and easy to use, while still providing a high degree of flexibility and control over the crawling process.

One of the key features of Gocrawl is its politeness, which means that it obeys the website's robots.txt file and respects the crawl-delay specified in the file. It also takes into account the website's last modified date, if any, to avoid recrawling the same page. This helps to reduce the load on the website and prevent any potential legal issues. Gocrawl is also highly concurrent, which allows it to efficiently crawl large numbers of pages in parallel. This helps to speed up the crawling process and reduce the time required to complete the task.

The library also offers a high degree of flexibility in customizing the crawling process. It allows you to specify custom callbacks and handlers for handling different types of pages, such as error pages, redirects, and so on. This allows you to handle and process the pages as per your requirement. Additionally, Gocrawl provides various functionalities such as support for cookies, user-agent, auto-detection of links, and auto-detection of sitemaps.

Ayakashi is a web scraping library for Node.js that allows developers to easily extract structured data from websites. It is built on top of the popular "puppeteer" library and provides a simple and intuitive API for defining and querying the structure of a website.

Features:

  • Powerful querying and data models
    Ayakashi's way of finding things in the page and using them is done with props and domQL. Directly inspired by the relational database world (and SQL), domQL makes DOM access easy and readable no matter how obscure the page's structure is. Props are the way to package domQL expressions as re-usable structures which can then be passed around to actions or to be used as models for data extraction.
  • High level builtin actions
    Ready made actions so you can focus on what matters. Easily handle infinite scrolling, single page navigation, events and more. Plus, you can always build your own actions, either from scratch or by composing other actions.
  • Preload code on pages
    Need to include a bunch of code, a library you made or a 3rd party module and make it available on a page? Preloaders have you covered.

Example Use


// Only enqueue the root and paths beginning with an "a"
var rxOk = regexp.MustCompile(`http://duckduckgo\.com(/a.*)?$`)

// Create the Extender implementation, based on the gocrawl-provided DefaultExtender,
// because we don't want/need to override all methods.
type ExampleExtender struct {
    gocrawl.DefaultExtender // Will use the default implementation of all but Visit and Filter
}

// Override Visit for our need.
func (x *ExampleExtender) Visit(ctx *gocrawl.URLContext, res *http.Response, doc *goquery.Document) (interface{}, bool) {
    // Use the goquery document or res.Body to manipulate the data
    // ...

    // Return nil and true - let gocrawl find the links
    return nil, true
}

// Override Filter for our need.
func (x *ExampleExtender) Filter(ctx *gocrawl.URLContext, isVisited bool) bool {
    return !isVisited && rxOk.MatchString(ctx.NormalizedURL().String())
}

func ExampleCrawl() {
    // Set custom options
    opts := gocrawl.NewOptions(new(ExampleExtender))

    // should always set your robot name so that it looks for the most
    // specific rules possible in robots.txt.
    opts.RobotUserAgent = "Example"
    // and reflect that in the user-agent string used to make requests,
    // ideally with a link so site owners can contact you if there's an issue
    opts.UserAgent = "Mozilla/5.0 (compatible; Example/1.0; +http://example.com)"

    opts.CrawlDelay = 1 * time.Second
    opts.LogFlags = gocrawl.LogAll

    // Play nice with ddgo when running the test!
    opts.MaxVisits = 2

    // Create crawler and start at root of duckduckgo
    c := gocrawl.NewCrawlerWithOptions(opts)
    c.Run("https://duckduckgo.com/")

    // Remove "x" before Output: to activate the example (will run on go test)

    // xOutput: voluntarily fail to see log output
}
const ayakashi = require("ayakashi");
const myAyakashi = ayakashi.init();

// navigate the browser
await myAyakashi.goTo("https://example.com/product");

// parsing HTML
// first by defnining a selector
myAyakashi
    .select("productList")
    .where({class: {eq: "product-item"}});

// then executing selector on current HTML:
const productList = await myAyakashi.extract("productList");
console.log(productList);

Alternatives / Similar


Was this page helpful?