Python Network Data Precipitation

Fly to the flowers, collect pollen. Processed Data cleaning storage programming available data

Urlib BeautifulSoup lxml scrapy pdfminer requests Selenium NLTK Pillow Unittset pysocks

API MySQL database openrefine data analysis tools for well-known websites

Phanthomjs Headless Browser

Tor Proxy Server content

-----------

About multi-process multiprocessing

Concurrent concurrency

Cluster cluster

such as high-performance acquisition is not much

Domestic and international laws on the protection of network data are constantly being formulated and perfected

The author introduces the laws and typical cases in the United States related to network data collection

Call on the web crawler to strictly control the speed of network data collection and reduce the burden of the collection of Web services legal issues

Language is the interpreter of thought data is the carrier of language

Bug is a challenge in product declaration good product is the result of constantly facing bugs and overcoming bugs

--------

Get up 6 o'clock every day

Magic tricks

Network Data precipitation web scraping

Witchcraft Wizardry

It is not difficult to write a simple web crawler first to collect the data and then display it to the command line or store it in the database.

GitHub

---------

Https://github.com/REMitchell/python-scraping

-------------

Screen Scraping

Data mining

Web Harvesting

-------------

Bots robot

--------

If the only way you surf the Internet is with a browser

Then you've lost a lot of possibilities.

The API of Twitter or Wikipedia discovers that an API provides different data types at the same time

------

Market Forecast machine Language Translation medical diagnosis field on news website Article Health Forum data Collection

-----

Jonathan Harris

Sep Kamvar

Started in 2006, we felt good.

Wefeelfine

http://wefeelfine.org/

Project

Grab a lot from a lot of English blogs

I feel

I am feeling the beginning of the statement

Describe how the world feels every minute of the day

-------

"Python language and its Applications" written by Bill Lubanovic

Jessica McKellar's Instructional video

Http://shop.oreilly.com/product/110000448.do

-----------

Http://www.safaribooksonline.com

---------

Crawler for domain name switching information collection and information storage functions

Nexus Browser of 1990

The browser itself is a program that can be decomposed into many basic components that can be reused for rewriting

-----------------------------------

are divided into sub-modules

Urllib.request

Urllib.parse

Urllib.error

There are modules inside the library.

----------

Python's standard library

The name of the BeautifulSoup library was taken from Lewis Carroll's "Alice in Wonderland" poem of the same name.

To the magic of the dull

----

Sickness, myrrh, Scourge.

-------

BS4

BeautifulSoup

-----------

sudo apt-get install PYTHON-BS4

Mac

sudo easy_install pip

Pip

Pip Install Beautifulsoup4

------------

Prettify---Modification

-----

BsObj.html.body.h1

BsObj.body.h1

BsObj.html.h1

-----------------

What if I crawl up and down the machine?

-------------

If the server does not exist, Urlopen will return a none object

Beautiful object is not found when the return is None

The label below the label has no words

would have

Attributeerror Error

---

 import urllib.request 
 from urllib.error import httperror 
 from BS4 import BeautifulSoup 
 def gettit            Le (URL): 
 Try: 
 Html=urllib.request.urlopen (HTML) 
 except Httperror as E: 
        Return None 
 Try: 
 Bsobj=beautifulsoup (Html.read ()) 
 Title=bsobj.body.h1 
 Except Attributeerror as E: 
 return None 
 return title 
 Title=gettitle ("Http://www.pythonscr Aping.com/pages/page1.html ") 
 if Title==none: 
 Print (" title cannot be empty ") 
 Else: 
 Print (title) 
-----------
 Michelangelo 
 How to Complete "David" 
 It's easy to use a hammer to knock off a rock where it doesn't look like david. 
 =----------
 Page parsing puzzle (Gordian knot) 
 When a site administrator changes the site slightly This line of code will fail or even ruin the entire web crawler 
-------------
 Look for a link to print this page 
 See if the website has a better HTML-style mobile version 
 Set your request header to be mobile and accept the website mobile 
 
 
 Looking for information hidden inside JavaScript files 
 I used to organize the street addresses on a Web site into a neat array when 
 viewed embedded Google JavaScript files 
 
 
 The site title can also get 
 
 
 
 
from the URL link of the Web page

If you're looking for information that just exists on a site somewhere else without

Think twice before you write code.

--------------

Lambda expression

is essentially a function

Can be used as a variable for other functions

A function is not defined as f (x, Y)

It is defined as f (g (x), y)

or F (g (X), H (x)) Form

----

BeautifulSoup allows us to treat a particular function type as an argument to the FindAll function

The only limiting condition is

These functions must take a label as a parameter and return the result as a Boolean type

BeautifulSoup uses this function to evaluate every tag object it encounters.

The final evaluation results are true for label retention to delete other tags

Soup.findall (Lambda Tag:len (tag.attrs) ==2)

This line of code will find the following label:

<div class= "Body" id= "content" ></div>

<span style= "color:red" class= "title" ></span>

-----

Lambda expression selection tag will be the perfect alternative to regular expression

-------

In addition to using BeautifulSoup (one of the most popular HTML parsing libraries in Python)

lxml (http://lxml.de/) parsing HTML XML documents

Very low level implementations most of the source code is written in C.

The more steep the learning curve, the quicker you can learn it.

Working with HTML documents is quick

-----------

HTML Parser Python's own parsing library

No installation

Https://docs.python.org/3/library/html.parser.html

----------

The Python Dictionary object is returned

You can get and manipulate these properties

myimgtag.attrs[[SRC]

----------------

Nature is a recursive

Using a web crawler, you must carefully consider how much network traffic you need to consume

---

And try to think about whether you can get a lower load on the capture target server.

---------

Wikipedia six-degree segmentation theory

-----

Kay Wembeken (Kevin Bacon)

Six-degree separated value game

Two unrelated themes in two games

Wikipedia is a link between entries.

Kevin Becken is linked with actors appearing in the same movie

Link to a topic with a total of no more than six articles, including the original two topics

http://oracleofbacon.org/index.php

------------

From urllib.request import Urlopen From BS4 import BeautifulSoup Html=urlopen ("Http://en.wikipedia.org/wiki/Kevin_Bacon") bsobj=beautifulsoup (HTML) For link in Bsobj.findall ("a"): if ' href ' in link.attrs: print (link.attrs[' href ') ---------- Each page of Wikipedia is filled with a sidebar header footer link
Connect to the Category Pages dialog page links to other pages that do not contain terms:
To determine if Wikipedia's inner chain is linked to an entry
He wrote a big filter function.
Over 100 lines of code
Unfortunately,
Did not take time to compare when the project was started
Differences between the entry links and other links
---
URL link does not contain a semicolon
In the DIV tag where the ID is bodycontent
URL links are all beginning with/wiki
----------
Online testing of regular expressions on the http://regexpal.com/website
-----------
The specific rules for mailbox addresses for different mailbox servers vary
--------
Regular Expressions for mailboxes
---------
[a-za-z0-9\._+] [Email protected] [A-za-z]+\. (com|org|edu|net)
----------
We're going to build a reptile behind us.
Also follow the link from one page to another page
Paint a map of the web
This time no longer ignore the chain to follow the outside chain jump
Is it possible for a crawler to record information on a page that we've browsed?
Compared to the single domain capture we did before
Internet acquisition is much more difficult
The layout of different Web sites is very disparate
means that the information we have to find and the way we find it is very flexible.
-------------
Sesame Street
http://www.sesamestreet.org
------------
What data do I need to collect? Can this data be completed by capturing several identified sites?
My crawler needs to find sites that I might not know about?
--
My crawler to a station is immediately follow the outbound link to a new station or on the site
In-depth collection of content on the site
Are there any kind of websites I don't want to collect?
Interested in the content of non-English websites?

My behavior caused suspicion of a website webmaster.
How do I avoid legal responsibility

------
One of the challenges of writing web crawlers is that you often have to repeat some simple characters
Find all the links on the page to differentiate the inner chain outside the chain jump to the new page
-------
Http://scrapy.org/dowmload 

Python Network Data precipitation