I'm going through crawling wikipedia using website downloader for windows, i was looking through the whole options in this tool to find an option to download wikipedia pages for specific period, for example from 2005 untill now.
Does anyone get any idea about crawling the website in specific period of time ?
Why not download the SQL database containing all of Wikipedia?
You can then query it using SQL.
Give a try to the Wikipedia API and your programming skills.
There should be no need to do web scraping; use the MediaWiki API to directly request the information you want. I'm not sure what you mean by "wikipedia pages for a specific period" - do you mean last edited at a certain time? If so, while skimming, I noticed an API call that lets you get a look at the last n revisions; just ask for the last revision and see what its date is.
It depends if the website in question offers the archive and mostly don't so its not possible in a straightforward way to crawl a sample started from specific date. But you can implement some intelligence in your crawler to read the page created date or something like that.
But you can also look at Wikipedia API at http://en.wikipedia.org/w/api.php
Related
I use Kimonolabs right now for scraping data from websites that have the same goal. To make it easy, lets say these websites are online shops selling stuff online (actually they are job websites with online application possibilities, but technically it looks a lot like a webshop).
This works great. For each website an scraper-API is created that goes trough the available advanced search page to crawl all product-url's. Let's call this API the 'URL list'. Then a 'product-API' is created for the product-detail-page that scrapes all necessary elements. E.g. the title, product text and specs like the brand, category, etc. The product API is set to crawl daily using all the URL's gathered in the 'URL list'.
Then the gathered information for all product's is fetched using Kimonolabs JSON endpoint using our own service.
However, Kimonolabs will quit its service end of february 2016 :-(. So, I'm looking for an easy alternative. I've been looking at import.io, but I'm wondering:
Does it support automatic updates (letting the API scrape hourly/daily/etc)?
Does it support fetching all product-URL's from a paginated advanced search page?
I'm tinkering around with the service. Basically, it seems to extract data via the same easy proces as Kimonolabs. Only, its unclear to me if paginating the URL's necesarry for the product-API and automatically keeping it up to date are supported.
Any import.io users here that can give advice if import.io is a usefull alternative for this? Maybe even give some pointers in the right direction?
Look into Portia. It's an open source visual scraping tool that works like Kimono.
Portia is also available as a service and it fulfills the requirements you have for import.io:
automatic updates, by scheduling periodic jobs to crawl the pages you want, keeping your data up-to-date.
navigation through pagination links, based on URL patterns that you can define.
Full disclosure: I work at Scrapinghub, the lead maintainer of Portia.
Maybe you want to give Extracty a try. Its a free web scraping tool that allows you to create endpoints that extract any information and return it in JSON. It can easily handle paginated searches.
If you know a bit of JS you can write CasperJS Endpoints and integrate any logic that you need to extract your data. It has a similar goal as Kimonolabs and can solve the same problems (if not more since its programmable).
If Extracty does not solve your needs you can checkout these other market players that aim for similar goals:
Import.io (as you already mentioned)
Mozenda
Cloudscrape
TrooclickAPI
FiveFilters
Disclaimer: I am a co-founder of the company behind Extracty.
I'm not that much fond of Import.io, but seems to me it allows pagination through bulk input urls. Read here.
So far not much progress in getting the whole website thru API:
Chain more than one API/Dataset It is currently not possible to fully automate the extraction of a whole website with Chain API.
For example if I want data that is found within category pages or paginated lists. I first have to create a list of URLs, run Bulk Extract, save the result as an import data set, and then chain it to another Extractor.Once set up once, I would like to be able to do this in one click more automatically.
P.S. If you are somehow familiar with JS you might find this useful.
Regarding automatic updates:
This is a beta feature right now. I'm testing this for myself after migrating from kimonolabs...You can enable this for your own APIs by appending &bulkSchedule=1 to your API URL. Then you will see a "Schedule" tab. In the "Configure" tab select "Bulk Extract" and add your URLs after this the scheduler will run daily or weekly.
I have used scrapy and beautiful soup many times, however find kimonolabs solution much easier and faster. The only problem is that sometimes jobs do need a bit of tweaking, which is not possible (e.g., crawling using a unique pattern).
Is there any other solution which combines the ease with optional complexity? Mainly I want to define a page scraping template using a WYSIWYG interface, and then programatically write the crawler.
Use an Import.io extractor.
Download the Import.io browser
Create an extractor (what you call a "scraping template")
From your code use the extractor's REST API
Full disclosure: I'm one of the founders of ParseHub.
ParseHub tries to solve exactly this problem. It gives you a gui and powerful tools for defining templates visually, and falls back to a subset of javascript if you need more fine-grained control. All of the programming primitives that you're familiar with (if, for, break, recursion, etc.) are available.
You can find it at www.parsehub.com
Try Agenty
Agenty has exact same feature to scrape websites, and the Chrome extension to setup the scraping agents. You can just install the extension and create agents to scrape any site.
FYI : We also have plan to launch hosted solution and REST API by April, 2016 (Update - API is available now)
You may see more details on website (www.datascraping.co) now Agenty.com
Disclosure : I'm one of the founding member
I'm looking for a portlet like-solution that would collect and report usage analytics in Liferay... but google analytics is not an option, unfortunately.
Stats by community, group, session tracking, apart from the usual bounce and exit rates, referrals, origin, etc. I know I'm kind of asking the reinvention of the wheel, but there are plenty of usage data that can be collected by Liferay that google can't. I've already checked PiWik, and it looks very impressive.
Any suggestions? TIA,
As of 2015 there is Audience Targeting plugin, which (at least for Liferay 6.2) comes bundled with analytics-api / analytics-hook modules, which collect some useful analytics data. Mind now:
So far it doesn't look like there is any standalone use for them as they were introduced, I believe, to enable the content visited, page visited and other such rules in the Audience Targeting itself; you can't see the raw events in any of the provided portlets
The events are stored as rows in a SQL database, so I would be concerned about it's performance in the long run (with thousands of clicks every minute etc.), although I say this purely theoretically as I haven't done any tests myself nor checked if there are some performance enhancing measures implemented
What you can do, however, is to put together your own portlet which would create some graphs etc. based on the data stored in CT_Analytics_AnalyticsEvent table.
Right now, I dont think there is any out of the box feature available for this, you might need to create this. There can be 2 things
1) You need to create a javascript library if you need realtime/web analysis (this is same like creating google analytics lib)
2) This option is quite easy. Liferay stores everything in db, you can have a report portlet which will show the report based on the data. We did this for one project where we were tracking the session ids/ip and logged in user details for portlets.
To achieve point 2) you can create new Liferay service, which will be used to store these data and retrieve.
Hope this helps
You already mention Piwik, which is similar to google analytics. You probably have your own theme (almost everybody changes the appearance to look like their own site) and it's quite appropriate to place the relevant piwik-stats-snippet in there.
You can also, as Felix suggests, mine your log files. Liferay stores some data, your webserver access logs also are quite worth to mine. And, of course, you can change your theme to log even more for every page access, just take care that you don't create a performance bottleneck by writing too much during one page request.
So, coming back to your question: Built-in like google analytics: No. Easily integrateable (like Piwik): Yes, of course. Completely customizeable: Yes, of course.
Edit: It just happens that David has created and documented an integration that makes using Piwik even easier
I'm curious about website scraping (i.e. how it's done etc..), specifically that I'd like to write a script to perform the task for the site Hype Machine.
I'm actually a Software Engineering Undergraduate (4th year) however we don't really cover any web programming so my understanding of Javascript/RESTFul API/All things Web are pretty limited as we're mainly focused around theory and client side applications.
Any help or directions greatly appreciated.
The first thing to look for is whether the site already offers some sort of structured data, or if you need to parse through the HTML yourself. Looks like there is an RSS feed of latest songs. If that's what you're looking for, it would be good to start there.
You can use a scripting language to download the feed and parse it. I use python, but you could pick a different scripting language if you like. Here's some docs on how you might download a url in python and parse XML in python.
Another thing to be conscious of when you write a program that downloads a site or RSS feed is how often your scraping script runs. If you have it run constantly so that you'll get the new data the second it becomes available, you'll put a lot of load on the site, and there's a good chance they'll block you. Try not to run your script more often than you need to.
You may want to check the following books:
"Webbots, Spiders, and Screen Scrapers: A Guide to Developing Internet Agents with PHP/CURL"
http://www.amazon.com/Webbots-Spiders-Screen-Scrapers-Developing/dp/1593271204
"HTTP Programming Recipes for C# Bots"
http://www.amazon.com/HTTP-Programming-Recipes-C-Bots/dp/0977320677
"HTTP Programming Recipes for Java Bots"
http://www.amazon.com/HTTP-Programming-Recipes-Java-Bots/dp/0977320669
I believe that the most important thing you must analyze is which kind of information do you want to extract. If you want to extract entire websites like google does probably your best option is to analyze tools like nutch from Apache.org or flaptor solution http://ww.hounder.org If you need to extract particular areas on unstructured data documents - websites, docs, pdf - probably you can extend nutch plugins to fit particular needs. nutch.apache.org
On the other hand if you need to extract particular text or clipping areas of a website where you set rules using DOM of the page probably what you need to check is more related to tools like mozenda.com. with those tools you will be able to set up extraction rules in order to scrap particular information on a website. You must take into consideration that any change on a webpage will give you an error on your robot.
Finally, If you are planning to develop a website using information sources you could purchase information from companies such as spinn3r.com were they sell particular niches of information ready to be consume. You will be able to save lots of money on infrastructure.
hope it helps!.
sebastian.
Python has the feedparser module, located at feedparser.org that actually handles RSS in its various flavours and ATOM in its various flavours. No reason to reinvent the wheel.
I've been experimenting with writing my own RSS reader. I can handle the "parse XML" bit. The thing I'm getting stuck on is "How do I fetch older posts?"
Most RSS feeds only list the 10-25 most recent items in their XML file. How do I get ALL the items in a feed, and not just the most recent ones?
The only solution I could find was using the "unofficial" Google Reader API, which would be something like
http://www.google.com/reader/atom/feed/http://fskrealityguide.blogspot.com/feeds/posts/default?n=1000
I don't want to make my application dependent on Google Reader.
Is there any better way? I noticed that on Blogger, I can do "?start-index=1&max-results=1000", and on WordPress I can do "?paged=5". Is there any general way to fetch an RSS feed so that it gives me everything, and not just the most recent items?
RSS/Atom feeds does not allow for historic information to be retrieved. It is up to the publisher of the feed to provide it if they want such as in the blogger or wordpress examples you gave above.
The only reason that Google Reader has more information is that it remembered it from when it came up the first time.
There is some information on something like this talked about as an extension to the ATOM protocol, but I don't know if it is actually implemented anywhere.
As the other replies here mentioned, a feed may not provide archival data but historical items may be available from another source.
Archive.org’s Wayback Machine has an API to access historical content, including RSS feeds (if their bots have downloaded it). I’ve created the web tool Backfeed that uses this API to regenerate a feed containing concatenated historical items. If you'd like to discuss the implementation in detail please get in touch.
In my experience with RSS, the feed is compiled by the last X items where X is a variable. Certain Feeds may have the full list, but for bandwidth sake most places are likely limiting to just the last few items.
The likely answer for google reader having the old info, is that it is storing it on its side for users later.
Further to what David Dean said the RSS/Atom feeds will only contain what the publisher of the feed has up at that moment and someone would need to be actively collecting this informaton in order to have any historical information. Basically Google Reader was doing this for free and when you interacted with it you could retrieve this stored informaton from the google database servers.
Now that they have retired the service, to my knowledge you have two choices. You either have to start collection of this information from your feeds of interest and store the data using XML or some such, or you could pay for this data from one of the companies who sell this type of archived feed information.
I hope this information helps somebody.
Seán
Another potential solution that might not have been available when the question was originally asked and shouldn't require any specific service.
Find the URL of the RSS feed you want and use waybackpack to get the archived urls for that feed.
Use FeedReader or a similar library to pull down the archived RSS feed.
Take the URLs from each feed and scrape them as you wish. If you're going way back in time it's possible there might be some dead links.
All previous answers more or less relied on existing services to still have a copy of that feed or the feed engine to be able to provide older items dynamically.
There's though another, admittedly pro-active and rather theoretical way to do so: Let your feedreader use a caching proxy which semantically understands RSS and/or Atom feeds and caches them on a per-item base up to as many items as you configure.
If the feedreader doesn't poll feeds regularily, the proxy could fetch known feeds time-based on its own to not miss an item in highly volatile feeds like the one from User Friendly which has only one item and changes every day (or at least used to do so). Hence if the feedreadere.g. crashed or lost network connection while you are away for a few days, you might loose items in your feedreader's cache. Having the proxy to fetch those feeds regularily (e.g. from a data center instead from at home or on a server instead of a laptop) allows you to easily run the feedreader only then and when without loosing items which were posted after your feedreader fetched feeds the last time but rotated out again before you fetch them the next time.
I call that concept a Semantic Feed Proxy and I've implemented a proof of concept implementation called sfp. It's though not much more than a proof of concept and I haven't developed it further. (So I'd be happy about hints to projects with similar ideas or purposes. :-)
Why does this problem exist?
Most RSS readers need to import feeds through a live URL, which makes things harder for sites that are unindexed on Wayback Machine.
The reason why Wayback Machine feeds can be imported is that the reader can regularly poll the server for updates according to its defined TTL configuration. The reader compares the current datetime with the RSS feed posts pubDate or lastBuildDate keys in the XML response. We can't hack the machine datetime to work around the datetime resolution because the current datetime is fetched live.
I've outlined an alternative solution without Wayback below. Unfortunately, I have not been able to find a universal solution for all feed sources.
Alternative Solution(s)
In my experience, NOT ALL feeds are partial though. The XML doesn't have to specify the datetime of each post. This means the RSS Reader doesn't have a datetime to filter the feed with. An example of this feed type can be found here.
This kind of reading experience is useful when chronological order is irrelevant, and the content doesn't need to be sorted. This approach is useful for sites where ALL the content is valuable, and the linked Essays of Paul Graham is a good example.
If the site has a generic, non-chronological feed option, subscribe to that RSS instead (the preferred option).
Download the linked timestamped .rss file, strip datetimes and host the file on your own server. Note, we can implement this via an AWS Lambda.
Set up a server that fetches the RSS from live.
Strip the pubDate tags from the XML file on fetch.
Host the modified RSS on your own server.
Note
These are suboptimal solutions due to loss of orders, however, I wanted to provide a potential alternative to WaybackMachine.
In addition, some existing answers require advanced SysDesign workarounds, more prework and in some cases are outdated (Google Reader is shut down). I hope it's helpful for those who really need a solution for a complete feed list. Constructing new RSS feeds is not too hard from the original RSS file.