Программирование на Python_IBM.pdf

1

Python (IBM):

1. ............... ......... 2

2. ......... 9

3. ........................................................ ....... 17

4. ....... .............................................................. ....... 25

5. ........ ...................................................................... 33

6. ......... ...................................................................... 38

7. ..................... 45

8. .............................................................. 53

9. ............................................................ 60

10. ............................................. 66

11. Web-: Django ..................................... 73

12. (TDD). PyUnit .............. 79

.........................................................

2

Python: 1.

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(tuple); (list); (dictionary).

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. , . , . tuple() .

. , . list().

-, -. , - -. , , . , , / . dict().

1 , Python.

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[ ] #

{ 5:a, 6:b, 7:c } # int

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Python , ; , . , .

Python ; :

def _():

1

2

...

, def, . :

_()

, Python, . Java, ( , , ), ( ).

, , , , :

8

#, //

def foo(delimoe, delitel):

return delimoe // delitel

print divide(50,5) # : 10

print divide(delitel=5, delimoe=50) # : 10

Python return, , , return, None, . , Python , - , return, , return , , return None.

, , Python - (lambda). lambda- ( ), return, . , , ( , ).

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9

Python. 2:

, ,

: Python. .

, , . .

1. . 2. (slicing). 3. . 4. Unicode. 5. . 6. . 7. .

1.

. Python , immutable . :

>>> word = 'strength'

>>> word[2] = 'y'

TypeError: 'str' object does not support item assignment

, , , :

>>> word = word[:3] + '!' + word[4:]

'str!ngth'

:

>>> word = word.replace('!','e')

'strength'

-1:

>>> word[-1]

h

, , :

>>> '123'

'123'

>>> "7'8''9"

"7'8''9"

10

:

>>> s = 'this is first word\

and this is second word'

:

>>> print """

One

Two

Three

"""

escape-.

.

'\n' , '\t' :

>>> s ='a\nb\tc'

>>> print s

a

b c

:

>>> s = '\001\002\x03'

>>> s

'\x01\x02\x03'

>>> len(s)

3

, , , , .

2.

.

. , 0. , :

>>> word = 'strength'

>>> word[4]

n

>>> word[0:2]

st

>>> word[2:4]

re

, , ; :

11

>>> word[:3]

str

>>> word[5:]

gth

:

>>> s = '1234567890'

>>> s[::2]

'13579'

>>> s[1:10:2]

'13579'

>>> s[::-1]

'0987654321'

3.

+ :

>>> var = 'Moscow' + 'city'

, .

* :

>>> '123' * 3

'123123123'

=.

4. Unicode

Unicode , . 256 .

u 2 , UTF-8:

>>> w = u' '

>>> w

u'\u0412\u0430\u0441\u044f \u041f\u0443\u043f\u043a\u0438\u043d'

: ASCII, UTF-8, UTF-16, KOI8-R, CP1251, CP866 ..:

>>> s = unicode("", "KOI8-R")

>>> s

u'\u043f\xf7\u044f\u2500\u043f\u2566\u043f\u2561\u043f\u2563\u044f\u250c'

encode() Unicode , :

>>> s.encode("KOI8-R")

'\xd0\x9f\xd1\x80\xd0\xb8\xd0\xb2\xd0\xb5\xd1\x82'

12

5.

. .

%. , :

>>> s = 'Hello %s' % 'word'

>>> s

'Hello word'

>>> s = 'one %s %s' % ('two','three')

>>> s

'one two three'

, %d %f:

>>> s = 'one %d %f' % (2 , 3.5)

>>> s

'one 2 3.500000'

, . 10 , 5 :

>>> x = 4/3

>>> '%10.5f' % x

' 1.00000'

:

>>> from math import pi

>>> '%015.10f' % pi

'0003.1415926536'

, Template. :

>>> from string import Template

>>> s = Template('1 $two 3 4 $five')

>>> d={}

>>> d['two']=2

>>> d['five']=5

>>> s.substitute(d)

'1 2 3 4 5'

13

s

r , repr, str

c

d

i

u , d (no longer unsigned)

o

x

X

e Floating-point exponent,

E , e,

f Floating-point decimal

F Floating-point decimal

g Floating-point e f

C Floating-point E F

% %

6.

. :

find , -1:

>>> s = 'The find method finds a substring'

>>> s.find('find')

4

>>> s.find('finds')

16

>>> s.find('findsa')

-1

join :

>>> seq = ['one','two','three']

>>> sep = ','

>>> sep.join(seq)

'one,two,three'

split join, :

>>> s = '/usr/local/bin'

>>> s.split('/')

['', 'usr', 'local', 'bin']

replace :

>>> s = 'replace method returns a string'

>>> s.replace('returns','return')

'replace method return a string'

14

strip :

>>> ' this is whitespace string '.strip()

'this is whitespace string'

translate replace, .

'1' '3', '2' '4' :

>>> from string import maketrans

>>> table = maketrans('12', '34')

>>> '1212 5656'.translate(table)

'3434 5656'

str, int, ord, chr:

str ;

int ;

ord ;

chr .

, Python 3.0 S.capitalize()

S.ljust(width [, fill]) S.center(width [, fill])

S.lower() S.count(sub [, start [, end]])

S.lstrip([chars]) S.encode([encoding [,errors]])

S.maketrans(x[, y[, z]]) S.endswith(suffix [, start [, end]])

S.partition(sep) S.expandtabs([tabsize])

S.replace(old, new [, count]) S.find(sub [, start [, end]])

S.rfind(sub [,start [,end]]) S.format(fmtstr, *args, **kwargs)

S.rindex(sub [, start [, end]]) S.index(sub [, start [, end]])

S.rjust(width [, fill]) S.isalnum()

S.rpartition(sep) S.isalpha()

S.rsplit([sep[, maxsplit]]) S.isdecimal()

S.rstrip([chars]) S.isdigit()

S.split([sep [,maxsplit]]) S.isidentifier()

S.splitlines([keepends]) S.islower()

S.startswith(prefix [, start [, end]]) S.isnumeric()

S.strip([chars]) S.isprintable()

S.swapcase() S.isspace()

S.title() S.istitle()

S.translate(map) S.isupper()

S.upper() S.join(iterable)

S.zfill(width)

15

7.

. , , : , .

: 0 .

1- . array.

, array.tostring(). .

2- . , , array , .

3- . cStringIO, -,

. getvalue().

4- . ,

. , append(). , .

16

:

import time

loop_count = 1000000

def method1():

from array import array

char_array = array('c')

for num in xrange(loop_count):

char_array.fromstring(`num`)

return char_array.tostring()

def method2():

str_list = []


str_list.append(`num`)

return ''.join(str_list)

def method3():

from cStringIO import StringIO

file_str = StringIO()


file_str.write(`num`)

return file_str.getvalue()

def method4():

return ''.join([`num` for num in xrange(loop_count)])

t1 = time.time()

method1()

t2 = time.time()

print "\t%.1f" % ((t2 - t1))

method2()

t3 = time.time()

print "\t%.1f" % ((t3 - t2))

method3()

t4 = time.time()

print "\t%.1f" % ((t4 - t3))

method4()

t5 = time.time()

print "\t%.1f" % ((t5 - t4))

. , , , , - . , , . . , Python. 2.6.

17

Python. 3:

, ,

: , Python . , .

. Java C . , Java Vector, . Perl. , , .

.

1. . 2. . 3. . 4. . 5. (Tuple). 6. (Set).

7. filter(), map(), zip(), reduce().

1.

list, , , . , .. . () . (performance) .

1. . 2. . 3. , , ..

, . 4. , 3.

5. , , O(n). 6. , , .

. :

>>> lst = ['spam', 'drums', 100, 1234]

, . , :

>>> lst[1:3]

['drums', 100]

18

, :

>>> lst[3] = 'piano'

>>> lst[0:2] = [1,2]

>>> lst

[1, 2, 100, 'piano']

:

>>> lst[1:1] = ['guitar','microphone']

>>> lst

[1, 'guitar', 'microphone', 2, 100, 'piano']

:

>>> numbers = [1,2,3,4,5,6,7,8,9,0]

>>> numbers[::4]

[1, 5, 9]

2.

:

; ; ; (list comprehension); sequence unpacking.

.

1. L1 = L2[:] . .

2. L1 = list(L2) .

3. L1 = L2 , . 3- , , .

:

L1 + L2

, :

L1 * 2

:

:

for x in L:

:

for x in sorted(L):

19

:

for x in set(L):

:

for x in reversed(L):

, 1- , 2- :

for item in set(L).difference(L2)

, , list comprehension 10 :

>>> a = [ i*i for i in range(1,10)]

>>> a

[1, 4, 9, 16, 25, 36, 49, 64, 81]

:

>>> a = [ i*i for i in range(1,10) if i % 2 == 0]

>>> a

[4, 16, 36, 64]

:

words = ' to perform the task of sorting the words in a string by their length'.split()

wordlens = [(len(word), word) for word in words]

wordlens.sort()

print ' '.join(w for (_, w) in wordlens)

>>> a by in of to the the task their words length string perform sorting

Sequence unpacking :

a, b = [1,2]

3.

:

append , extend ;

insert ;

index ;

count ;

remove , del ;

sort ;

reverse ;

pop ;

len ;

max ;

min ;

20

in .

, .

append():

>>> lst = [1, 'guitar', 'microphone', 2, 100, 'piano']

>>> lst2 = ['sintezator','drums']

>>> lst.append(lst2)

>>> lst

[1, 'guitar', 'microphone', 2, 100, 'piano', ['sintezator', 'drums']]

insert:

>>> lst.insert(0,'vocal')

>>> lst

['vocal', 1, 'guitar', 'microphone', 2, 100, 'piano', ['sintezator', 'drums']]

, , in:

>>> 2 in lst

True

>>> 10 in lst

False

index() :

>>> lst.index('guitar')

2

count() - :

>>> lst.count('vocal')

1

remove() :

>>> lst.remove(100)

>>> lst

['vocal', 1, 'guitar', 'microphone', 2, 'piano', ['sintezator', 'drums']]

del :

del lst[1]

, .

sort() :

>>> lst.sort()

>>> lst

[1, 2, ['sintezator', 'drums'], 'guitar', 'microphone', 'piano', 'vocal']

reverse() :

>>> lst.reverse()

>>> lst

21

['vocal', 'piano', 'microphone', 'guitar', ['sintezator', 'drums'], 2, 1]

pop() , , :

>>> lst.pop()

>>> lst

['vocal', 'piano', 'microphone', 'guitar', ['sintezator', 'drums'], 2]

len() :

>>> len(lst)

6

max() :

>>> max(lst)

'vocal'

min() :

>>> min(lst)

2

extend() append(), :

>>> lst.extend([3,4])

>>> lst

['vocal', 'piano', 'microphone', 'guitar', ['sintezator', 'drums'], 2, 3, 4]

4.

(LIFO, last-in, first-out). pop():

>>> stack = [1,2,3,4,5]

>>> stack.append(6)

>>> stack.append(7)

>>> stack.pop()

>>> stack

[1, 2, 3, 4, 5, 6]

,

(FIFO, first-in, first-out). pop()

0:

>>> queue = ['rock','in','roll']

>>> queue.append('alive')

>>> queue.pop(0)

>>> queue

['in', 'roll', 'alive']

22

5. (Tuple)

(immutable), ,

(tuple). , . ( ). , , , :

>>> t = 1,[2,3]

>>> t

(1, [2, 3])

>>> t[1] = 2

TypeError: 'tuple' object does not support item assignment

>>> t[1].append(4)

>>> t

(1, [2, 3, 4])

tuple() :

>>> tuple('abc')

('a', 'b', 'c')

6. (Set)

. , .. . :

>>> s = set('abcde')

>>> s

set(['a', 'c', 'b', 'e', 'd'])

>>> s2 = set('aghij')

>>> s2

set(['a', 'h', 'j', 'g', 'f'])

, :

:

>>> s3 = s - s2

>>> s3

set(['c', 'b', 'e', 'd'])

:

>>> s3 = s | s2

>>> s3

set(['a', 'c', 'b', 'e', 'd', 'g', 'i', 'h', 'j'])

:

>>> s3 = s & s2

>>> s3

set(['a'])

23

:

add() :

>>> s.add(6)

>>> s

set(['a', 'c', 'b', 'e', 'd', 6])

remove() :

>>> s.remove('a')

>>> s

set(['c', 'b', 'e', 'd', 6])

:

>>> for item in s:print (item)

c

b

e

d

6

. , :

>>> L = [1,2,3,4,1,2,6,7]

>>> set(L)

set([1, 2, 3, 4, 6, 7])

>>> L = list(set(L))

>>> L

[1, 2, 3, 4, 6, 7]

:

, :

>>> programmers = set(['ivanov','petrov','sidorov'])

>>> managers = set(['ivanov','moxov','goroxov'])

, , :

>>> programmers & managers

set(['ivanov'])

:

>>> programmers | managers

set(['ivanov', 'petrov', 'sidorov', 'goroxov', 'moxov'])

, :

>>> programmers - managers

set(['petrov', 'sidorov'])

24

7. filter(), map(), zip(), reduce().

filter(function, sequence) , sequence, function(item) . . : 100:

def f(x):

for y in xrange(2, x):

if x%y==0: return 0

return 1

print filter(f, xrange(2, 100))

>>> [2, 3, 5, 7, 11, 13, 17, 19, 23, ... , 59, 61, 67, 71, 73, 79, 83, 89, 97]

map(function, sequence) , function . , 1 10:

def cube(x): return x*x*x

print map(cube, xrange(1, 11))

:

seq1 = [1,2,3]

seq2 = [11,12,13]

for x, y in map(None, seq1, seq2):

print x, y

>>> 1 11

>>> 2 12

>>> 3 13

zip(sequence) , map() , , :

>>> a = (1, 2, 3, 4)

>>> b = (5, 6, 7, 8)

>>> zip(a, b)

[(1, 5), (2, 6), (3, 7), (4, 8)]

reduce(function, sequence) ,

function sequence, . . , :

>>> def add(x, y): return x+y

...

>>> reduce(add, xrange(1, 11))

55

, Python . , . . , , , . .

25

2.6.

26

Python: 4.

, ,

: , . , , (mutable) , .

. , . :

1. , . , .

2. , , , .

3. , . (heterogeneous). immutable , , , float , .

4. - . 5. , , , .

.

1. . 2. / . 3. . 4. .

1.

(dictionary) .

: . {} . , , , , .

.

key: value del.

keys() ;

sort().

has_key(), 3.0 in. : , .

27

:

>>> dic = {'vanya' : 23323223, 'smith' : 32232332}

>>> dic['fedya'] = 33332222

>>> dic

{'vanya': 23323223, 'fedya': 33332222, 'smith': 32232332}

>>> dic['smith']

32232332

>>> del dic['vanya']

>>> dic

{'fedya': 33332222, 'smith': 32232332}

>>> dic.keys()

['fedya', 'smith']

>>> dic.has_key('fedya')

True

:

1. , :

D = {'name': 'mel', 'age': 45}

2. :

D = {}

D['name'] = 'mel'

D['age'] = 45

3. dict() . . :

d1 = dict(id=1948, name="Washer", size=3)

d2 = dict({"id": 1948, "name": "Washer", "size": 3})

d3 = dict([("id", 1948), ("name", "Washer"), ("size", 3)])

d4 = dict(zip(("id", "name", "size"), (1948, "Washer", 3)))

4. fromkeys() :

D = {}.fromkeys(['name', 'age'],123)

5. :

d = dict((x, x**2) for x in xrange(5))

28

2. /

dict() ;

len() ;

clear() ;

copy() ;

deepcopy() ;

fromkeys() ;

get() ;

has_key() ;

items() ;

iteriyems() ;

keys() ;

iterkeys() ;

pop() ;

popitem() ;

update() ;

values() ;

itervalues() .

in , ;

del , ;

dict() .

, :

>>> items = [('name','sveta'),('age',20)]

>>> d = dict(items)

>>> d

{'age': 20, 'name': 'sveta'}

>>> len(d)

2

in() .

: .

29

:

people = {'Alice': {'phone': '2341', 'addr': 'Foo drive 23' },

'Beth': {'phone': '9102', 'addr': 'Bar street 42'}}

name = 'Alice'

key = 'phone'

if name in people:

print "%s phone is %s" % (name, people[name][key])

>>> Alice phone is 2341

copy()

:

>>> x = {"user":'admin','attr':[1,2,3]}

>>> y = x.copy()

>>> y

{'user': 'admin', 'attr': [1, 2, 3]}

copy() : , , :

>>> x['attr'].remove(1)

, .

, deepcopy().

>>> from copy import deepcopy

>>> y = x.deepcopy()

fromkeys() :

>>> {}.fromkeys(['name', 'age'])

{'age': None, 'name': None}

:

>>> {}.fromkeys(['name', 'age'],123)

{'age': 123, 'name': 123}

get() , None:

>>> d = {}

>>> print d.get('name')

None

has_key() , :

>>> d = {}

>>> d.has_key('name')

False

items() :

for key, value in d.items():

print(key, value)

30

iteriyems() :

>>> for k, v in d.iteritems():

... print k, v

keys() ;

iterkeys() :

>>> d.keys()

['url', 'title']

>>> d.iterkeys()

pop() :

>>> d.pop('title')

>>> d

{'url': 'http://www.python.org'}

popitem() :

>>> d = {'title': 'Python Web Site', 'url': 'http://www.python.org', 'www': 'python'}

>>> d.popitem()

>>> d

{'www': 'python', 'title': 'Python Web Site'}

update() :

>>> d2 = {'www':'python.org'}

>>> d.update(d2)

>>> d

{'www': 'python.org', 'title': 'Python Web Site'}

values() :

>>> d={}

>>> d[1]=1

>>> d[2]=2

>>> d[3]=3

>>> d

{1: 1, 2: 2, 3: 3}

>>> d.values()

[1, 2, 3]

del : :

>>> del d[2]

>>> d

{1: 1, 3: 3}

3.

(map), , .

31

:

, for:

>>> table = {'Python': 'Guido van Rossum',

... 'Perl': 'Larry Wall',

... 'Tcl': 'John Ousterhout' }

>>> for lang in table:

... print(lang, table[lang])

..

>>> Tcl John Ousterhout

>>> Python Guido van Rossum

>>> Perl Larry Wall

:

>>> Matrix = {}

>>> Matrix[(2, 3, 4)] = 88

>>> Matrix[(7, 8, 9)] = 99

>>>

>>> X = 2; Y = 3; Z = 4

>>> Matrix[(X, Y, Z)]

88

>>> Matrix

{(2, 3, 4): 88, (7, 8, 9): 99}

:

>>> man = {'name': 'Serg',

... 'jobs': ['programmer', 'writer'],

... 'web': 'www.iakovlev.org',

... 'home': {'city': 'Moscow', 'zip':129000}}

>>> man['name']

Serg

>>> man['jobs'][1]

'writer'

4.

1. , :

def histogram(s):

d = dict()

for c in s:

if c not in d:d[c] = 1

else:d[c] += 1

return d

hist = histogram('how many times')

>>> {'a': 1,'e': 1,'i': 1,'h': 1,'m': 2,'o': 1,'n': 1,'s': 1,'t': 1,'w': 1,'y': 1}

32

:

def invert_dict(d):

inv = dict()

for key in d:

val = d[key]

if val not in inv:inv[val] = [key]

else:inv[val].append(key)

return inv

print invert_dict(hist)

>>> {1: ['a', 'e', 'i', 'h', 'o', 'n', 's', 't', 'w', 'y'], 2: [' ', 'm']}

2. :

import string

import sys

words = {}

strip = string.whitespace + string.punctuation + string.digits + "\"'"

filename = 'file'

for line in open(filename):

for word in line.lower().split():

word = word.strip(strip)

if len(word) > 2:

words[word] = words.get(word, 0) + 1

for word in sorted(words):

print("'{0}' occurs {1} times".format(word, words[word]))

3. :

author = {"php":"Rasmus Lerdorf",\

"perl":"Larry Wall",\

"tcl":"John Ousterhout",\

"awk":"Brian Kernighan",\

"java":"James Gosling",\

"parrot":"Simon Cozens",\

"python":"Guido van Rossum"}

# :

langs = author.keys()

langs.sort()

for language in langs:

print language," - ",author[language]

# :

for key in sorted(author.iterkeys()):

print "%s: %s" % (key, author[key])

>>> awk - Brian Kernighan

>>> java - James Gosling

>>> parrot - Simon Cozens

>>> perl - Larry Wall

>>> php - Rasmus Lerdorf

>>> python - Guido van Rossum

>>> tcl - John Ousterhout

33

4. , .. :

def invert_dict_nonunique(d):

newdict = {}

for k, v in d.iteritems():

newdict.setdefault(v, []).append(k)

return newdict

d = {'child1': 'parent1','child2': 'parent1','child3': 'parent2','child4': 'parent2'}

print invert_dict_nonunique(d)

>>> {'parent2': ['child3', 'child4'], 'parent1': ['child1', 'child2']}

: , . , , (mutable) , . . .

2.6.

34

Python: 5.

, ,

: . .

, . , .

:

: . : ,

, . , .

: , , , .

C .

1. . 2. . 3. . 4. . 5. .

1.

Python , . . . .py. my_module.py , , PYTHONPATH, , '.pth', . PYTHONPATH '.pth', . , , sys.path.

, , , -. . . . , namespace, , , .

35

2.

, (, my_module.py), :

>>> python

:

>>> import my_module

, :

>>> my_module.func1()

>>> my_module.func2()

...

:

>>> f1 = my_module.func1

:

>>> from my_module import func1, func2

>>> func1()

, :

>>> from my_module import *

>>> func1()

:

>>> from my_module import open as my_open

. from , read-only:

>>> from small import x, y

>>> x = 42

x , x, y small :

>>> import small

>>> small.x = 42

x .

import from , .

, reload().

36

, . , : ___.___ .

. import .

3.

, , my_module.pyc , my_module.py, , - my_module. , , my_module.py my_module.pyc. - - ( ), .

:

1. -O - '.pyo'. , , '.pyc'- .

2. -OO , , . 3. , , .

. 4. '.py' '.pyo',

'.py'. , .

5. , , '.so' '.dll' Windows.

6. '.zip' . 7. Java-, Jython.

4.

Python . 200 , - , : , , , + , GUI .. http://docs.python.org/library/.

, ; , , sys.

sys.path , . PYTHONPATH . :

37

>>> import sys

>>> sys.path.append(/home/my/lib/python)

, , dir(). :

>>> dir(sys)

['__displayhook__', '__doc__', '__egginsert', '__excepthook__', '__name__',

...

'stderr', 'stdin', 'stdout', 'subversion', 'version', 'version_info']

5.

. . . , , PYTHONPATH .

, , .

, , TCP. Server Client:

TCP/

_init_.py

main.py

Server/

_init_.py

tcp.py

server.py

lib.py

Client/

_init_.py

tcp.py

client.py

lib.py

_init_.py , , . . :

>>> import TCP.Server.lib

>>> import TCP.Client.lib

:

>>> import TCP.Server.lib.connect()

:

>>> from TCP.Server import lib as server_lib

>>> from TCP.Client import lib as client_lib

>>> server_lib.connect()

>>> client_lib.connect()

38

lib , , TCP.Server .. , .

:

>>> from TCP import *

__init__.py __all__ , , . :

__all__ = ["Server", "Client"]

. .

. . , . , . , .

, . Python. 2.6.

39

Python: 6.

, ,

: , , . , . . . , . , self. , , .

- () Python. , . .

1. : .

. count(),

: 'abc'.count('a') [1, 2,

'a'].count('a'). . 2. :

. . . , state.

3. : . .

4. : .

- .

1. , , .

2. . 3. . 4. .

. . :

i. use cases , ;

ii. .

- , , .

Python C++ Modula-3.

40

:

a. ; b. ; c. ; d. public, .. ;

, .. .

- .

1. . 2. . 3. self. 4. . 5. : .

1.

. :

class _:

1

.

. C++ , , . , :

_ = _()

. , . , .

, , . -, .

:

; .

2.

:

; -.

41

. , . def.

obj.attrname.

.

class Simple:

u' '

var = 87

def f(x):

return 'Hello world'

Simple.var Simple.f . :

>>> print Simple.__doc__

>>> print Simple.var.__doc__

int(x[, base]) -> integer

...

, :

smpl = Simple()

smpl. , - , , :

class Simple:

def __init__(self):

self.list = []

smpl list. :

class Simple:

def __init__(self, count, str):

self.list = []

self.count = count

self.str = str

>>> s = Simple(1,'22')

>>> s.count, s.str

1 22

(private) .. :

42

class Simple:

u' '

__private_attr = 10

def __init__(self, count, str):

self.__private_attr = 20

print self.__private_attr

s = Simple(1,'22')

print s.__private_attr

__private_attr .

:

def method_for_simple(self, x, y):

return x + y

class Simple:

f = method_for_simple

>>> s = Simple()

>>> print s.f(1,2)

3

:

class Customer:

pass

custom = Customer()

custom.name = ''

custom.salary = 100000

3. self

self. , : self .

self , :

class Simple:

def __init__(self):

self.list = []

def f1(self):

self.list.append(123)

def f2(self):

self.f1()

>>> s = Simple()

>>> s.f2()

>>> print s.list

[123]

Self "this" C++.

43

4.

:

class Derived(Base):

:

class Derived(module_name.Base):

: , , . . :

Base.method()

:

class Derived(Base1,Base2,Base3):

:

1. Derived; 2. Base1, Base1; 3. Base2, Base2 4. ..

5.

: Person , , ; Manager . Person str, . , __str__.

# -*- coding: utf-8 -*-

class Person:

def __init__(self, name, job=None, pay=0):

self.name = name

self.job = job

self.pay = pay

def lastName(self):

return self.name.split()[-1]

def giveRaise(self, percent):

self.pay = int(self.pay * (1 + percent))

def __str__(self):

return '[Person: %s, %s]' % (self.name, self.pay)

class Manager(Person):

def __init__(self, name, pay):

Person.__init__(self, name, 'mgr', pay)

def giveRaise(self, percent, bonus=100):

Person.giveRaise(self, percent + bonus)

44

Person:

>>> ivan = Person(' Petrov')

Person:

>>> john = Person('John Sidorov', job='dev', pay=100000)

__str__;

>>> print(ivan)

>>> print(john)

:

>>> print(ivan.lastName(), john.lastName())

:

>>> john.giveRaise(.10)

:

>>> print(john)

Manager:

>>> tom = Manager('Tom Jones', 50000)

:

>>> tom.giveRaise(.10)

:

print(tom.lastName())

print(tom)

:

[Person: Petrov, 0]

[Person: John Sidorov, 100000]

('Petrov', 'Sidorov')

[Person: John Sidorov, 110000]

Jones

[Person: Tom Jones, 5055000]

45

, , . , . . . , . , self. , , . () . , , . . . . , , , ' '.

. 2.6.

46

Python. 7:

, , ; open-source www.iakovlev.org. .

: , - .

Python. . , , , , , ..

.

1. . 2. . 3. . 4. . 5. Bound unbound . 6. super. 7. . 8. . 9. Property. 10. Singleton. 11. . 12. . 13. . 14. Sequence.

1.

- . - :

__name__ ;

__module__ ;

__dict__ , ;

__bases__ ;

__doc__ .

47

2.

() -. , ( ) . :

__dict__ , ;

__class__ -, ;

__init__ . , ;

__del__ . , ;

__cmp__ ;

__hash__ - , 32- ;

__getattr__ , ;

__setattr__ ;

__delattr__ ;

__call__ .

3.

. :

__len__ ;

__getitem__ ;

__setitem__ ;

__delitem__ ;

__getslice__ ;

__setslice__ ;

__delslice__ ;

__contains__ in.

48

4.

.

__repr__ ;

__str__ ;

__oct__ , __hex__ , __complex__ , __int__ , __long__ , __float__ .

5. Bound unbound

. Cat, Barsik:

class Cat:

def __init__(self):

self.hungry = True

def eat(self):

if self.hungry:

print 'I am hangry...'

self.hungry = False

else:

print 'No, thanks!'

class Barsik(Cat):

def __init__(self):

self.sound = 'Aaaammm!'

print self.sound

:

>>> brs = Barsik()

Aaaammm!

>>> brs.eat()

AttributeError: Barsik instance has no attribute 'hungry'

, hungry . , , , . . :

class Barsik(Cat):

def __init__(self):

Cat.__init__(self)


print self.sound

, Cat unbound-, , bound-. bound- .

49

6. super

: , , new-style. super :

__metaclass__ = type

...

class Barsik(Cat):

def __init__(self):

super(Barsik, self).__init__()


print self.sound

>>> brs = Barsik()

>>> brs.eat()

Aaaammm!

I am hangry...

7.

, self:

class Spam:

numInstances = 0

def __init__(self):

Spam.numInstances = Spam.numInstances + 1

def printNumInstances( ):

print "Number of instances created: ", Spam.numInstances

>>> a=Spam()

>>> b=Spam()

>>> printNumInstances()

Number of instances created: 2

staticmethod, , :

class Multi:

def imeth(self, x):

print self, x

def smeth(x):

print x

def cmeth(cls, x):

print cls, x

smeth = staticmethod(smeth)

cmeth = classmethod(cmeth)

>>> Multi.smeth(3)

3

>>> obj=Multi()

>>> obj.smeth(5)

5

classmethod (cls):

50

>>> Multi.cmeth(7)

__main__.Multi 7

>>> obj.cmeth(10)

__main__.Multi 10

8.

, , , .

__iter__ next. __iter__ next:

class Reverse:

def __init__(self, data):

self.data = data

self.index = len(data)

def __iter__(self):

return self

def next(self):

if self.index == 0:

raise StopIteration

self.index = self.index - 1

return self.data[self.index]

>>> for char in Reverse('12345'):

>>> print char

5

4

3

2

1

:

>>> rvr = list(Reverse('12345'))

>>> rvr

['5', '4', '3', '2', '1']

9. Property

Property , property, :

class DateOffset:

def __init__(self):

self.start = 0

def _get_offset(self):

self.start += 5

return self.start

offset = property(_get_offset)

>>> d = DateOffset()

>>> d.offset

5

>>> d.offset

10

51

10. Singleton

. __new__:

class Singleton(object):

def __new__(cls, *args, **kw):

if not hasattr(cls, '_instance'):

orig = super(Singleton, cls)

cls._instance = orig.__new__(cls, *args, **kw)

return cls._instance

>>> one = Singleton()

>>> two = Singleton()

>>> id(one)

3082687532

>>> id(two)

3082687532

11.

, __slots__. , :

class limiter(object):

__slots__ = ['age', 'name', 'job']

>>> x=limiter()

>>> x.age = 20

12.

, __call__ .

. Person, - people, . Sortkey:

class SortKey:

def __init__(self, *attribute_names):

self.attribute_names = attribute_names

def __call__(self, instance):

values = []

for attribute_name in self.attribute_names:

values.append(getattr(instance, attribute_name))

return values

class Person:

def __init__(self, forename, surname, email):

self.forename = forename

self.surname = surname

self.email = email

52

>>> people=[]

>>> p=Person('Petrov','','')

>>> people.append(p)

>>> p=Person('Sidorov','','')


>>> p=Person(u'Ivanov','','')


>>> for p in people:

... print p.forename

Petrov

Sidorov

Ivanov

>>> people.sort(key=SortKey("forename"))

>>> for p in people:

... print p.forename

Ivanov

Petrov

Sidorov

13.

, .

, __get__ , __set__ ,

__delete__, .

:

class ExternalStorage:

__slots__ = ("attribute_name",)

__storage = {}

def __init__(self, attribute_name):

self.attribute_name = attribute_name

def __set__(self, instance, value):

self.__storage[id(instance), self.attribute_name] = value

def __get__(self, instance, owner=None):

if instance is None:

return self

return self.__storage[id(instance), self.attribute_name]

class Point:

__slots__ = ()

x = ExternalStorage("x")

y = ExternalStorage("y")

def __init__(self, x=0, y=0):

self.x = x

self.y = y

>>> p1=Point(1,2)

>>> p2=Point(3,4)

Point x, y, , ExternalStorage.

53

14. Sequence

__getitem__, __setitem__. MySequence ,

: 1 3 5 7 ...

__del__ , __len__:

class MySequence:

def __init__(self, start=0, step=1):

self.start = start

self.step = step

self.changed = {}

def __getitem__(self, key):

return self.start + key*self.step

def __setitem__(self, key, value):

self.changed[key] = value

>>> s = MySequence(1,2)

>>> s[0]

1

>>> s[1]

3

>>> s[100]

201

, , - . , - . . , , . . , . . Python.

2.6.

; open-source www.iakovlev.org. .

54

Python: 8.


: .

Python . , , , .

.

1. . 2. . 3. /. 4. . 5. . 6. . 7. . 8. Pickling. 9. struct. 10. .

1.

open:

open(name[, mode[, buffering]])

. . , . (mode) open:

'r' .

'w' .

'a' .

'b' .

'+' /.

'+' . . 'rb'. . , / . .

55

2.

: sys.stdin, sys.stdout, , urllib.urlopen ..

:

>>> f = open('my_file', 'w')

>>> f.write('Hello, ')

>>> f.write('World!')

>>> f.close()

:

>>> f = open('my_file', 'r')

>>> f.read(5)

'Hello'

>>> f.read()

', World!'

3. /

, (pipe):

cat my_file | python test.py

cat my_file sys.stdout . , sys.stdin , :

test.py:

import sys

text = sys.stdin.read()

words = text.split()

wordcount = len(words)

print 'Wordcount:', wordcount

(pipe) , .

4.

read() , . seek:

seek(offset[, whence])

offset ;

whence , , .

56

:

>>> f = open(r'my_file', 'w')

>>> f.write('01234567890123456789')

>>> f.seek(5)

>>> f.write('Hello, World!')

>>> f.close()

>>> f = open(r'my_file')

>>> f.read()

'01234Hello, World!89'

tell() .

5.

. :

file.readline()

readline() , , . :

file.readlines()

:

file.writelines()

. :

f = open(r'my_file')

lines = f.readlines()

f.close()

lines[0] = "This is a my_file2 \n" # 1-

f = open(r'my_file2','w')

f.writelines(lines)

f.close()

6.

close(). , , .

1. , .

2. . 3. ,

. , , .

57

try/finally:

try:

#

finally:

file.close()

, :

with open("my_file") as somefile:

do_something(somefile)

, / flush(), . .

7.

. read() :

f = open(filename)

while True:

char = f.read(1)

if not char: break

process(char)

f.close()

readline():

f = open(filename)

while True:

line = f.readline()

if not line: break

process(line)

f.close()

:

for line in open(filename):

process(line)

8. Pickling

, . pickle:

import pickle

t1 = [1, 2, 3]

s = pickle.dumps(t1)

t2 = pickle.loads(s)

print t2

[1, 2, 3]

58

: t1 t2 , .

9.

struct C . . .

:

pack(format, value1, value2 ...)

, value1 ..., . , format.

unpack(format, string)

string format .

calcsize(format)

(.. ), format.

Format C Type Python

c char string of length 1

? Bool bool

i Int integer

l Long integer

f float float

d double float

s char[] string

, . , '4h' 'hhhh'. , .

's' , . '10s' 10 , '10c' 10 .

:

< - little-endian

> - big-endian

59

float, , , :

from struct import *

out = open("123.bin", "wb")

format = "if5s"

data = pack(format, 24,12.48,'12345')

out.write(data)

out.close()

input = open("123.bin", "rb")

data = input.read()

input.close()

format = "if5s" # one integer

value,value2,value3 = unpack(format, data) # note the ',' in 'value,':

unpack apparently returns a n-uple

print value

print value2

print value3

print calcsize(format)

>>> 24

>>> 12.4799995422

>>> 12345

>>> 13

10.

os . . os.getcwd :

import os

cwd = os.getcwd()

print cwd

:

os.path.exists('my_file')

:

os.listdir(path)

:

import os

def walk(dir):

for name in os.listdir(dir):

path = os.path.join(dir, name)

if os.path.isfile(path):

print path

else:

walk(path)

walk(path)

: , , . os.path.walk : , , :

60

import os, sys

def getlocaldata(sms,dr,flst):

for f in flst:

fullf = os.path.join(dr,f)

if os.path.islink(fullf): continue # don't count linked files

if os.path.isfile(fullf):

sms[0] += os.path.getsize(fullf)

sms[1] += 1

else:

sms[2] += 1

def dtstat(dtroot):

sums = [0,0,1] # 0 bytes, 0 files, 1 directory so far

os.path.walk(dtroot,getlocaldata,sums)

return sums

report = dtstat('.')

print report

grep. , 'import os':

import os, sys, fnmatch

mask = '*.py'

pattern = 'import os'

def walk(arg,dir,files):

for file in files:

if fnmatch.fnmatch(file,mask):

name = os.path.join(dir,file)

try:

data = open(name,'rb').read()

if data.find(pattern) != -1:

print name

except:

pass

os.path.walk('.',walk,[])

, /. . . / . . . . / , . , .

2.6.


61

Python: 9.


: , . .

. : .

, . exec fork. .

. . , .

.

. . . (Queue). (Lock).

1.

subprocess, , (pipe). , , . arent.py child.py. parent.py. Child.py command, . , . child.py, word . subprocess. . , child .

62

parent.py:

import os

import subprocess

import sys

child = os.path.join(os.path.dirname(__file__), "./child.py")

word = 'word'

file = ['./parent.py','./child.py']

pipes = []

for i in range(0,2):

command = [sys.executable, child]

pipe = subprocess.Popen(command, stdin=subprocess.PIPE)

pipes.append(pipe)

pipe.stdin.write(word.encode("utf8") + b"\n")

pipe.stdin.write(file[i].encode("utf8") + b"\n")

pipe.stdin.close()

while pipes:

pipe = pipes.pop()

pipe.wait()

child.py:

import sys

word = sys.stdin.readline().rstrip()

filename = sys.stdin.readline().rstrip()

try:

with open(filename, "rb") as fh:

while True:

current = fh.readline()

if not current:

break

if (word in current ):

print("find: {0} {1}".format(filename,word))

except :

pass

2.

, , (threads). . (multi-threading) , .

, . , , . :

for x in L

. : , .

63

. , , .

(deadlock) . : . , . , . . , .

. , , , .

, . .

. (GIL), . . , /, , , , .

3.

threading. :

threading.Thread()

threading.Thread

, :

import threading

import time

def clock(interval):

while True:

print("The time is %s" % time.ctime())

time.sleep(interval)

t = threading.Thread(target=clock, args=(15,))

t.daemon = True

t.start()

:

. start() -,

run():

64

import threading

import time

class ClockThread(threading.Thread):

def __init__(self,interval):

threading.Thread.__init__(self)

self.daemon = True

self.interval = interval

def run(self):

while True:

print("The time is %s" % time.ctime())

time.sleep(self.interval)

t = ClockThread(15)

t.start()

:

start() .

run() , .

join([timeout]) , , ,

, . timeout ( ) ( ),

, join . join()

. join() . .

getName() .

setName(name) name.

isAlive() , ( run() ).

isDaemon() , .

setDaemon(daemonic) daemonic , .

activeCount() Thread.

len(threading.enumerate()).

currentThread() -, .. , .

enumerate() .

4. (Queue)

, : ,

grep. work_queue ,

. Queue, :

65

import threading

import Queue

class Worker(threading.Thread):

def __init__(self, work_queue, word):

super(Worker,self).__init__()

self.work_queue = work_queue

self.word = word

def run(self):

try:

filename = self.work_queue.get()

self.process(filename)

finally:

pass

def process(self, filename):

previous = "

current=True

with open(filename, "rb") as fh:

while current:

current = fh.readline()

if not current: break

current = current.decode("utf8", "ignore")

if self.word in current :

print("find {0}: {1}".format(self.word,filename))

previous = current

word = 'import'

filelist = ['./file1.py','./file2.py','./file3.py']

work_queue = Queue.Queue()

for filename in filelist:

work_queue.put(filename)

for i in range(3):

worker = Worker(work_queue, word)

worker.start()

5. (Lock)

, Web-.

url_list threading.Lock().

Lock :

acquire([blocking=True]) . blocking , .

, .

blocking , True ( ).

(.. blocking=False), True,

. False.

release() .

locked() (True , False ).

66

import threading

from urllib import urlopen

class WorkerThread(threading.Thread):

def __init__(self,url_list,url_list_lock):

super(WorkerThread,self).__init__()

self.url_list=url_list

self.url_list_lock=url_list_lock

def run(self):

while (1):

nexturl = self.grab_next_url()

if nexturl==None:break

self.retrieve_url(nexturl)

def grab_next_url(self):

self.url_list_lock.acquire(1)

if len(self.url_list)

67

Python: 10.


: Python.

. . , : , , , Web-, , , CGI- .. , , . Python. socket . C/C++ , . Python : httplib, ftplib, telnetlib, smtplib, . , twisted, , .

.

1. TCP -. 2. TCP-. 3. Twisted. 4. Twisted . 5. Twisted . 6. Twisted -. 7. Twisted -.

1. TCP -

TCP . , , .

- . socket , . , .

: , . : , -, TCP-.

, bind(), ip- . , .

listen() , .

68

accept() , . .

recv() . .

send() .

close() .

raw_input() .

import socket

import sys

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

host = 'localhost'

port = 8007

s.bind((host), (port))

s.listen(1)

conn, addr = s.accept()

data = conn.recv(1000000)

print 'client is at', addr , data

conn.send(data)

z = raw_input()

conn.close()

, . connect()

. send() .

recv() . close() .

import socket

import sys

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

host = 'localhost'

port = 8007

s.connect((host, port))

s.send('hello')

data = s.recv(1000000)

print 'received', data, len(data), 'bytes'

s.close()

? , (wrappers)

. , socket.send() send() . (chunk).

, send() , , . , , . , .

69

2. TCP-

, accept() . , , . , . :

1. ; 2. ; 3. select/poll.

Python setblocking() , .

:

lstn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

cs = []

nc = 2

for i in range(nc):

(clnt,ap) = lstn.accept()

clnt.setblocking(0)

cs.append(clnt)

, .

select()

. poll().

3. Twisted

Twisted - , Python. , . mail, web, news, chat, DNS, SSH, Telnet, RPC, ..

Linux twisted. , : http://twistedmatrix.com/projects/core/

Twisted event. , event handler. event loop. , . . event loop twisted , reactor, twisted.internet . :

reactor.run()

70

4. Twisted Protocol

Protocol, twisted.internet.protocol.Protocol. . , . :

from twisted.internet.protocol import Protocol

class Echo(Protocol):

def dataReceived(self, data):

self.transport.write(data)

. , , . , connect:

from twisted.internet.protocol import Protocol

class Connector(Protocol):

def connectionMade(self):

self.transport.write("Connection made ... \r\n")

self.transport.loseConnection()

, . connectionMade . connectionLost .

5. Twisted Factory

Factory, twisted.internet.protocol.Factory. , . , , factory, . , -:

from twisted.internet.protocol import Factory

from twisted.protocols.basic import LineReceiver

class LoggingProtocol(LineReceiver):

def lineReceived(self, line):

self.factory.fp.write(line+'\n')

class LogfileFactory(Factory):

protocol = LoggingProtocol

def __init__(self, fileName):

self.file = fileName

def startFactory(self):

self.fp = open(self.file, 'a')

def stopFactory(self):

self.fp.close()

71

6. Twisted Client-Server

: dataReceived :

from twisted.internet.protocol import Factory, Protocol

from twisted.internet import reactor

class Server(Protocol):


self.transport.write(self.factory.quote+'\r\n')

def connectionLost(self, reason):

print 'connection lost ...'


print data

self.transport.write(data)

class ServerFactory(Factory):

protocol = Server

def __init__(self, quote=None):

self.quote = quote

reactor.listenTCP(8007, ServerFactory("quote"))

reactor.run()

, callLater:


from twisted.internet.protocol import Protocol, ClientCreator

class Client(Protocol):

def sendMessage(self, msg):

self.transport.write("%s\n" % msg)

for i in range(1,5):

self.transport.write("%d\n" % i)


print data

def gotProtocol(p):

p.sendMessage("Hello")

reactor.callLater(1, p.sendMessage, "world")

reactor.callLater(2, p.transport.loseConnection)

c = ClientCreator(reactor, Client)

c.connectTCP("localhost", 8007).addCallback(gotProtocol)

reactor.run()

:

Hello

1

2

3

4

world

1

2

3

4

connection lost ...

72

7. Twisted -

- , , . , , , . clientProtocols. connectionMade ChatProtocol . -:


from twisted.internet.protocol import ServerFactory

from twisted.protocols.basic import LineOnlyReceiver

class ChatProtocol(LineOnlyReceiver):

name = ""

def getName(self):

if self.name!="":

return self.name

return self.transport.getPeer().host


print "New connection from "+self.getName()

self.sendLine("Welcome to my my chat server.")

self.sendLine("Send '/NAME [new name]' to change your name.")

self.sendLine("Send '/EXIT' to quit.")

self.factory.sendMessageToAllClients(self.getName()+" has joined the party.")

self.factory.clientProtocols.append(self)

def connectionLost(self, reason):

print "Lost connection from "+self.getName()

self.factory.clientProtocols.remove(self)

self.factory.sendMessageToAllClients(self.getName()+" has disconnected.")

def lineReceived(self, line):

print self.getName()+" said "+line

if line[:5]=="/NAME":

oldName = self.getName()

self.name = line[5:].strip()

self.factory.sendMessageToAllClients(oldName+" changed name

to "+self.getName())

elif line=="/EXIT":

self.transport.loseConnection()

else:

self.factory.sendMessageToAllClients(self.getName()+" says "+line)

def sendLine(self, line):

self.transport.write(line+"\r\n")

class ChatProtocolFactory(ServerFactory):

protocol = ChatProtocol

def __init__(self):

self.clientProtocols = []

def sendMessageToAllClients(self, mesg):

for client in self.clientProtocols:

client.sendLine(mesg)

print "Starting Server"

factory = ChatProtocolFactory()

reactor.listenTCP(12345, factory)

reactor.run()

73

telnet:

>> telnet localhost 12345

, TCP . TCP - . ,

. select() poll() . twisted , , .

Python 2.6.


74

Python: 11. Web-: Django


: Python Django. , , Python Django .

-- (Model-View-Controller) MVC, . : .

Web-, MVC. , Web-, Web-.

:

(url); ; .

- .

1. : Web-. , . . - (ORM) . ORM, SQL. , -. . , Web-.

2. (view): , , . View , - (url) .

3. : . .

4. URL: (view). . , . : .

75

, , , - . . , , : , , , . , :

http://projects.washingtonpost.com/congress/

http://www.ljworld.com/

http://www.lawrence.com/

.

1. . 2. . 3. . 4. . 5. . 6. .

1.

, 2.3. -: , :

http://www.djangoproject.com/download/.

:

setup.py install

, :

> import django

:

> django.VERSION

1.1.1.

2.

:

django-admin.py startproject mysite

mysite, . :

76

mysite/

__init__.py

manage.py

settings.py

urls.py

__init__.py , .

manage.py , .

settings.py .

urls.py .

Web-, :

python manage.py runserver

:

Validating models...

0 errors found.

Django version 1.1, using settings 'mysite.settings'

Development server is running at http://127.0.0.1:8000/

Quit the server with CONTROL-C.

http://127.0.0.1:8000/, , : .

3.

: PostgreSQL, SQLite, MySQL, Microsoft SQL Server, Oracle.

, , . , , . settings.py :

DATABASE_ENGINE = 'postgresql_psycopg2'

DATABASE_NAME = 'mysite'

DATABASE_USER = 'postgres'

TIME_ZONE = 'Europe/Moscow'

LANGUAGE_CODE = 'ru-ru'

, mysite , , :

psql -d template1 -U postgres -c "DROP DATABASE mysite;"

psql -d template1 -U postgres -c "CREATE DATABASE mysite

WITH OWNER postgres ENCODING='UNICODE';"

, 10 :

python manage.py syncdb

77

4.

Web-:

python manage.py startapp People

mysite People :

People/

__init__.py

models.py

tests.py

views.py

settings.py , :

INSTALLED_APPS = (

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.sites',

'mysite.People'

)

settings.py :

ROOT_URLCONF = 'mysite.urls'

Person , -. models.py:

from django.db import models

class Person(models.Model):

name = models.CharField('name', max_length=200)

email = models.EmailField('Email', blank=True)

def __str__(self):

return '%s' % (self.name)

, . :


. , , : . sql- .

, - views.py:

from django.shortcuts import HttpResponse

from mysite.People.models import Person

def index(request):

html = "People !!!"

return HttpResponse(html)

78

urls.py:

from django.conf.urls.defaults import *

urlpatterns = patterns('',

(r'^People/$', 'mysite.People.views.index')

)

Web-:


:

http://127.0.0.1:8000/People/

5.

mysite templates. settings.py :

TEMPLATE_DIRS = (

"/home/mysite/templates"

)

. person.htnl :

People !!!

Personal Information

Name: {{p.name}}

Email: {{ p.email }}

index : Person . :

{{p.name}}

{{p.email}}

views.py :

from mysite.People.models import Person

from django.shortcuts import render_to_response, get_object_or_404

def index(request):

person = Person()

person.name = 'Alex'

person.email = '[email protected]'

return render_to_response('person.html', {'p': person})

79

Web- .

6.

. settings.py:

INSTALLED_APPS = (

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.sites',

'mysite.People',

'django.contrib.admin'

)

, :

python manage.py createsuperuser

:


urls.py :

from django.conf.urls.defaults import *

from django.contrib import admin

admin.autodiscover()

urlpatterns = patterns('',

(r'^admin/', include(admin.site.urls)),

(r'^People/$', 'mysite.People.views.index')

)

Web-:


: http://127.0.0.1:8000/admin/. . . .

, , . , MVC, , , .. Web- : http://www.djangoproject.com/ . . : , . . , , , .

80

: PyUnit(unittest)

, ,

: , .

, unittest, .

(Test fixture). , , (test case).

(test case), . , .

(test suite) unittest. Test Suite , . , .

(test runner). , . .

. .

, , , python 2.6. random ( 1).

1.

#!/usr/bin/env python

#-*- coding:cp1251 -*-

import unittest

import random

class TestSequenceFunctions(unittest.TestCase):

def testshuffle(self):

'''

, shuffle

'''

self.seq = range(10)

random.shuffle(self.seq)

self.assertNotEqual(self.seq, range(10))

if __name__=="__main__":

unittest.main()

81

( 2).

2. 1

.

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

Ran 1 test in 0.000s

OK

, , ( , , , unittest.main()). , , , . TestSequenceFunctions.

testshuffle.

! , test. , , 0 () .

test , - , . , : _testshuffle.

.

1. . self.seq = range(10) 2. shaffle random. random.shuffle(self.seq) 3.

.

. , , , . , TestCase, , , , , .

. choice random. choice . TestSequenceFunction ( 3).

3. choice

def testchoice(self):

'''

choice

'''


element = random.choice(self.seq)

self.assert_(element in self.seq)

82

, , testshaffle. . , unittest.TestCase, , . TestCase 20 .

, . . .

. , , , .

. . , . ,

, .

, . , , . , ?

unittest.TestCase setUp tearDown, . , ( 4).

4. setUp tearDown

#!/usr/bin/env python

#-*- coding:cp1251 -*-

import unittest

import random

class TestSequenceFunctions(unittest.TestCase):

def setUp(self):


def testshuffle(self):

'''

, shuffled

'''

random.shuffle(self.seq)

self.assertNotEqual(self.seq, range(10))

def testchoice(self):

'''

choice

'''

element = random.choice(self.seq)

self.assert_(element in self.seq)

def tearDown(self):

del self.seq


unittest.main()

83

4 setUp tearDown. . setUp . tearDown , .

, .

, , , , , , .

. python , . , , ? unittest.TestCase? . , setUp tearDown. unittest.TestCase.

. , . . , , . , ?

, , . . , python (TestSuit).

unittest.TestSuit , addTest addTests, . (TestCase), (TestSuit), 5.

5. TestSuit

suite = unittest.TestSuite()

suite.addTest(unittest.makeSuite(testEx1))

suite.addTest(unittest.makeSuite(testEx2))

unittest.TestSuite().

testEx1 testEx2 .

, , . :

84

suite.addTest (suite1),

suite1 , , , testEx3, testEx4 .. suite2, suite3.

, suit. testEx1, testEx2, testEx3 .., .

( 6).

6.

if __name__==__main__:

unittest.main()

main() unittest .

main() , , .

:

[] []

:

;

[] , (. 1);

[] / .

1. unittest.main

-h --help -v --verbose

-q --quiet

, testex1.py ( 7).

85

7.

import unittest

import ex1.py

class testEx1(unittest.TestCase):

def setUp(self):

...

...

def testex11(self):

...

...

...

def testex12(self):

...

...

...


unittest.main()

testex1.py unittest.main(), 8.

8. main

..

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


OK

. , - , 'F'. , , 'E', .

- , v --verbose ( 9).

9. main

#> textex1.py v

testex11 (__main__.testex1) ... ok

testex11 (__main__.testex1) ... ok

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


OK

unittest.main , , . . , . unittest TestRunner(), , . , python.

86

, . , (assertsion), Python ( ).

Web-: Django (TDD). PyUnit

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