quickscrape

quickscrape is a simple command-line tool for powerful, modern website scraping.

Table of Contents

• Description
• Installation
• Documentation
• Examples
  • 1. Extract data from a single URL with a predefined scraper
• Contributing
• Release History
• License

Description

quickscrape is not like other scraping tools. It is designed to enable large-scale content mining. Here's what makes it different:

Websites can be rendered in a GUI-less browser (PhantomJS via CasperJS). This has some important benefits:

• Many modern websites are only barely specified in their HTML, but are rendered with Javascript after the page is loaded. Headless browsing ensures the version of the HTML you scrape is the same one human visitors would see on their screen.
• User interactions can be simulated. This is useful whenever content is only loaded after interaction, for example when article content is gradually loaded by AJAX during scrolling.
• The full DOM specification is supported (because the backend is WebKit). This means pages with complex Javascripts that use rare parts of the dom (for example, Facebook) can be rendered, which they cannot in most existing tools.

Scrapers are defined in separate JSON files that follow a defined structure (scraperJSON). This too has important benefits:

• No programming required! Non-programmers can make scrapers using a text editor and a web browser with an element inspector (e.g. Chrome).
• Large collections of scrapers can be maintained to retrieve similar sets of information from different pages. For example: newspapers or academic journals.
• Any other software supporting the same format could use the same scraper definitions.

quickscrape is being developed to allow the community early access to the technology that will drive ContentMine, such as ScraperJSON and our Node.js scraping library thresher.

The software is under rapid development, so please be aware there may be bugs. If you find one, please report it on the issue tracker.

Installation

Prerequisites

You'll need Node.js (node), a platform which enables standalone JavaScript apps. You'll also need the Node package manager (npm), which usually comes with Node.js. Installing Node.js via the operating system's package manager leads to issues. If you already have Node.js installed, and it requires sudo to install node packages, that's the wrong way. The easiest way to do it right on Unix systems (e.g. Linux, OSX) is to use NVM, the Node version manager.

First, install NVM:

curl https://raw.githubusercontent.com/creationix/nvm/v0.24.1/install.sh | bash

or, if you don't have curl:

wget -qO- https://raw.githubusercontent.com/creationix/nvm/v0.24.1/install.sh | bash

NB: on OSX, you will need to have the developer tools installed (e.g. by installing XCode).

Then, install the latest Node.js, which will automatically install the latest npm as well, and set that version as the default:

source ~/.nvm/nvm.sh
nvm install 0.10
nvm alias default 0.10
nvm use default

Now you should have node and npm available. Check by running:

node -v
npm -v

If both of those printed version numbers, you're ready to move on to installing quickscrape.

Quickscrape

quickscrape is very easy to install. Simply:

npm install --global quickscrape

Documentation

Run quickscrape --help from the command line to get help:

Usage: quickscrape [options]

Options:

-h, --help               output usage information
-V, --version            output the version number
-u, --url <url>          URL to scrape
-r, --urllist <path>     path to file with list of URLs to scrape (one per line)
-s, --scraper <path>     path to scraper definition (in JSON format)
-d, --scraperdir <path>  path to directory containing scraper definitions (in JSON format)
-o, --output <path>      where to output results (directory will be created if it doesn't exist
-r, --ratelimit <int>    maximum number of scrapes per minute (default 3)
-h --headless            render all pages in a headless browser
-l, --loglevel <level>   amount of information to log (silent, verbose, info*, data, warn, error, or debug)
-f, --outformat <name>   JSON format to transform results into (currently only bibjson)

You must provide scraper definitions in ScraperJSON format as used in the ContentMine journal-scrapers.

Examples

1. Extract data from a single URL with a predefined scraper

First, you'll want to grab some pre-cooked definitions:

git clone https://github.com/ContentMine/journal-scrapers.git

Now just run quickscrape:

quickscrape \
  --url https://peerj.com/articles/384 \
  --scraper journal-scrapers/scrapers/peerj.json \
  --output peerj-384
  --outformat bibjson

You'll see log messages informing you how the scraping proceeds:

Then in the peerj-384 directory there are several files:

$ tree peerj-384
peerj-384/
  └── https_peerj.com_articles_384
    ├── bib.json
    ├── fig-1-full.png
    ├── fulltext.html
    ├── fulltext.pdf
    ├── fulltext.xml
    └── results.json

• fulltext.html is the fulltext HTML (duh!)
• results.json is a JSON file containing all the captured data
• bib.json is a JSON file containing the results in bibJSON format
• fig-1-full.png is the downloaded image from the only figure in the paper

results.json looks like this (truncated):

{
  "publisher": {
    "value": [
      "PeerJ Inc."
    ]
  },
  "journal_name": {
    "value": [
      "PeerJ"
    ]
  },
  "journal_issn": {
    "value": [
      "2167-8359"
    ]
  },
  "title": {
    "value": [
      "Mutation analysis of the SLC26A4, FOXI1 and KCNJ10 genes in individuals with congenital hearing loss"
    ]
  },
  "keywords": {
    "value": [
      "Pendred; MLPA; DFNB4; \n          SLC26A4\n        ; FOXI1 and KCNJ10; Genotyping; Genetics; SNHL"
    ]
  },
  "author_name": {
    "value": [
      "Lynn M. Pique",
      "Marie-Luise Brennan",
      "Colin J. Davidson",
      "Frederick Schaefer",
      "John Greinwald Jr",
      "Iris Schrijver"
    ]
  }
}

bib.json looks like this (truncated):

{
  "title": "Mutation analysis of the SLC26A4, FOXI1 and KCNJ10 genes in individuals with congenital hearing loss",
  "link": [
    {
      "type": "fulltext_html",
      "url": "https://peerj.com/articles/384"
    },
    {
      "type": "fulltext_pdf",
      "url": "https://peerj.com/articles/384.pdf"
    },
    {
      "type": "fulltext_xml",
      "url": "/articles/384.xml"
    }
  ],
  "author": [
    {
      "name": "Lynn M. Pique",
      "institution": "Department of Pathology, Stanford University Medical Center, Stanford, CA, USA"
    },
    {
      "name": "Marie-Luise Brennan",
      "institution": "Department of Pediatrics, Stanford University Medical Center, Stanford, CA, USA"
    }
  ]
}

Contributing

We are not yet accepting contributions, if you'd like to help please drop me an email ([email protected]) and I'll let you know when we're ready for that.

Release History

• 0.1.0 - initial version with simple one-element scraping
• 0.1.1 - multiple-member elements; clean exiting; massive speedup
• 0.1.2 - ability to grab text or HTML content of a selected node via special attributes text and html
• 0.1.3 - refactor into modules, full logging suite, much more robust downloading
• 0.1.4 - multiple URL processing, bug fixes, reduce dependency list
• 0.1.5 - fix bug in bubbling logs up from PhantomJS
• 0.1.6 - add dependency checking option
• 0.1.7 - fix bug where jsdom rendered external resources (#10)
• 0.2.0 - core moved out to separate library: thresher. PhantomJS and CasperJS binaries now managed through npm to simplify installation.
• 0.2.1 - fix messy metadata
• 0.2.3 - automatic scraper selection
• 0.2.4-5 - bump thresher dependency for bug fixes
• 0.2.6-7 - new Thresher API
• 0.2.8 - fix Thresher API use
• 0.3.0 - use Thresher 0.1.0 and scraperJSON 0.1.0
• 0.3.1 - update the reported version number left out of last release
• 0.3.2 - fix dependencies
• 0.3.3-6 - bug fixes
• 0.3.7 - fix bug in bibJSON dates. Bump to thresher 0.1.3.
• 0.4.0 - fix various bugs (with urllists, tokenized urls), print help when run with no args, update all dependencies.
• 0.4.1 - fix version number reporting.

License

Copyright (c) 2014 Shuttleworth Foundation Licensed under the MIT license.