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scrape-news

Scrape South African news to provide search with links to the original articles.

This is important because search engines make no guarantee of including all articles. It's important to be able to find news articles even if search engines didn't think they're worth indexing.

Contribution

We need very broad coverage of news outlets. Contributed spiders are very welcome. Any South African news is welcome.

It's really easy to contribute spiders. Basically you can copy an existing spider and change the xpaths to find the elements we're extracting.

See the In Progress column at https://trello.com/b/9TVRB4gb/public-people to see which publications are currently being tackled to avoid duplication.

Next, go get started at Development

Copyright of news content

We do not make news content available for public consumption. We simply store and index the news content and the original URL and publication date to provide search functionality similar to search engines. This project intends to provide better access to news on the publisher's website. It should be used to send readers to relevant news websites rather than to replace them.

Development

Set up your development environment

Fork this repository on GitHub and clone your fork:

git clone https://github.com/your-name/scrape-news.git

or

git clone git@github.com:your-name/scrape-news.git

(Make sure to replace your-name.)

Create a Python 2 virtual environment for this project inside the cloned project directory (Note: your virtual environment program might not be called pyvenv -

cd scrape-news
pyvenv env

If your default Python is Python3, try virtualenv instead; it creates a Python2 environment by default:

cd scrape-news
virtualenv .env2
source .env2/bin/activate
pip install -r requirements.txt

Run a scraper to check that your environment is working properly. The argument since_lastmod is the earliest sitemap file and page the scraper will include. The setting ITEM_PIPELINES disables the pipeline we have configured which you don't need for just developing a spider.

scrapy crawl iol -s ITEM_PIPELINES="{}" -a since_lastmod=2018-04-30

If it's working correctly, it will output a lot of information:

e.g. after starting up it will find the sitemap and some articles that it will ignore in the sitemaps:

2018-05-03 18:21:17 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.iol.co.za/robots.txt> (referer: None) ['cached']
2018-05-03 18:21:17 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.iol.co.za/sitemap.xml> (referer: https://www.iol.co.za/robots.txt) ['cached']
2018-05-03 18:21:18 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.iol.co.za/personal-finance/sitemap.xml> (referer: https://www.iol.co.za/sitemap.xml)
2018-05-03 18:21:18 [scrapenews.spiders.sitemap] DEBUG: Skipping too old https://www.iol.co.za/personal-finance/utmost-good-faith-is-the-cornerstone-of-insurance-14626128
2018-05-03 18:21:18 [scrapenews.spiders.sitemap] DEBUG: Skipping too old https://www.iol.co.za/personal-finance/facebooks-lesson-on-being-priced-for-perfection-14625488
2018-05-03 18:21:18 [scrapenews.spiders.sitemap] DEBUG: Skipping too old https://www.iol.co.za/personal-finance/six-cappuccinos-or-a-year-off-your-home-loan-14626132

when it reaches articles that are after the earliest accepted date, it will actually scrape content from the pages and print the resulting ScrapenewsItem for the article

2018-05-03 18:21:34 [scrapy.core.scraper] DEBUG: Scraped from <200 https://www.iol.co.za/personal-finance/stanlib-may-further-reduce-fund-offering-14717297>
{'body_html': u'<div itemprop="articleBody" class="article-body" ... the ratings, De Klerk says.</p>\n<!-- C-ON- TEXT_CONTENT_END --></div></div>',
 'byline': u'Mark Bechard',
 'file_name': 'stanlib-may-further-reduce-fund-offering-14717297',
 'publication_name': 'IOL News',
 'published_at': '2018-04-30T15:04:00+02:00',
 'retrieved_at': '2018-05-03T16:21:31.603070',
 'spider_name': 'iol',
 'title': u'Stanlib may further reduce fund offering',
 'url': 'https://www.iol.co.za/personal-finance/stanlib-may-further-reduce-fund-offering-14717297'}

Make a spider

Public People needs the following fields:

field description
body_html An HTML string that contains all the text of the article and any other content the publication had in the article body. Don't bother filtering ads or anything - just try and exclude headers and footers and make sure you have the entire article, even if it's broken into multiple sections on the page.
byline String of all the authors' names and surnames as presented on the article page.
file_name Usually the "slug" of the article in the URL. Some simple clear name for the article if it was a file.
publication_name e.g. News24 - this can usually be hardcoded in the scraper and doesn't need to be scraped from the page.
published_at ISO 8601 date - could even be partial, like just the year-month-date part excluding time. There's often a meta tag or an attribute on the element in the content where the date is for search engines - that value is often already in ISO 8601 format.
retrieved_at ISO 8601 date of current date/time to know when we scraped it.
spider_name Generally the module name.
title Article title.
url This is used as the unique identifier for this article for deduplication, so use the canonical url meta tag value if available, otherwise just try to parse out the unique part of the URL from resposne.url and exclude things like query string paramaters and URL fragment identifier.

First, add this repository as a remote and make sure your local master is up to date:

git remote add upstream git@github.com:public-people/scrape-news.git
git fetch upstream
git checkout master
git merge upstream/master

Create and check out a branch for the spider you're making:

git checkout -b newssite

(Replace newssite with the name of the publication you're making a spider for.)

Ideally spiders should be driven from the outlet's sitemap. Ideally you'll find the sitemap from /robots.txt. If you don't find it there, try /sitemap.xml or /sitemap.txt.

If the newssite uses a useful sitemap index (see for example https://www.timeslive.co.za/sitemap/), use a sitemap spider.

If the sitemap index is less useful (see for example https://www.dailyvoice.co.za/sitemap.xml), or if there isn't a sitemap index (or no sitemap at all), use a crawling spider.

Copy a spider from the repository and amend it as necessary: a good example of a sitemap spider is iol; a good example of a crawling spider is dfa).

Test your responses

To test individual xpath or css responses you can use the scrapy shell:

scrapy shell "https://www.newssite.co.za/article-url"

If you go to the same url in your browser and right-click on, say, the title of the article, and select 'Inspect Element (Q)', you'll see something like

<h1 class="article-title">Title of article</h1>

highlighted. In the scrapy shell you can then enter

>>> response.css('h1.article-title').xpath('text()').extract_first()

to get the title.

Now that you've checked that this works and doesn't have some unintended consequence, you can copy it into the relevant part of your spider; in this case:

def parse(self, response):
    ...
    title = response.css('h1.article-title').xpath('text()').extract_first()
    ...

Do not use xpath for css classes

You could have also used the xpath in the above, but the preference is to use css lookup for classes. e.g.:

>>> response.xpath('//h1/[@class="article-title"]/text()').extract_first()

The reason for this is that xpaths can be brittle in more complicated instances. Consider the case of

<div class="byline pin-right">John Smith</div>

The only way an xpath query will work here is if you give the exact class name:

>>> response.xpath('//div/[@class="byline pin-right"]/text()').extract_first()

which means that if the same publication uses, say, byline pin-left for certain articles the spider won't get a response for 'byline'. (And if you were using extract() instead of extract_first() it would get an error.) The safer option is therefore to use the following instead:

>>> response.css('div.byline').xpath('text()').extract_first()

Test and improve

Once you have all your paths figured out (fun, right? – have a look at the existing spiders for ideas on how to get around any issues you encounter, or shout on Slack), you can run it a couple of times to check that it works as expected and refine it. This is especially important for crawling spiders.

Exit from the scrapy shell (Ctrl+D) and run your spider:

scrapy crawl newssite -s ITEM_PIPELINES="{}" -a since_lastmod=2018-04-30

(Don't include the since_lastmod specification if it's a crawling spider.)

If it runs, yay! But the odds are that there will be some errors thrown; so search for the word 'error' in your output and see if you can figure out what's causing it – there's usually a pattern.

Another thing to look out for is 'ignoring': if the urls being ignored by your spider follow a pattern, consider adding some paths to 'deny' instead to save resources.

Make a pull request

Once your spider is done and ready for review, git add it and commit the change to your working branch.

Then, first make sure your local master is up to date:

git fetch upstream
git checkout master
git merge upstream/master

and merge any changes into your working branch:

git merge master newssite

Then push your newssite branch to your fork on GitHub (use git remote -v to check the names of your remotes):

git push origin newssite

Go to Pull requests, choose to 'compare across forks', and compare the base fork: public-people/scrape-news, base: master to head fork: your-name/scrape-news, compare: newssite, and make a new pull request!

If you make some changes to your spider after your initial pull request, do the following to update the PR:

# check you're up to date
git fetch upstream
git checkout master
git merge upstream/master
git merge master newssite

# push your changes
git checkout newssite
git add newssite.py
git commit -m "Make changes to newssite spider to incorporate/address review comments"
git push origin newssite

If git fetch upstream doesn't return anything you can skip the next steps until checking out your newssite branch.

Pushing the same branch again will automatically update your existing PR.

Deployment

We use scrapyd to run the scrapers.

We use cron to schedule the scrapers regularly.

Deploy a scraper to scrapyd

scrapyd-deploy

Schedule a scraper

SitemapSpider scrapers can run daily, fetching only the latest articles. Crawling scrapers have to visit every page on the site so we only run them weekly.

Tunnel a connection to the server if you're not scheduling it from the server:

ssh -L 6800:localhost:6800 username@hostname

Schedule a SitemapSpider

SitemapSpiders take an argument since_lastmod which is an ISO format date filtering sitemaps and links in sitemaps. To do a complete scrape, just set it to a date very long ago, like 1900-01-01.

curl -v http://localhost:6800/schedule.json -d project=scrapenews -d spider=iol -d setting=ALEPH_API_KEY=... -d since_lastmod=$(date +%Y-%m-%d -d "5 day ago")

Schedule a crawling spider

curl -v http://localhost:6800/schedule.json -d project=scrapenews -d spider=thenewage -d setting=ALEPH_API_KEY=...