convert pdf to image asp.net c#: Secure pdf remove Library software class asp.net winforms wpf ajax O'Reilly%20-%20Python%20Cookbook44-part1472

10.14 Module: Interactive POP3 Mailbox Inspector

Credit: Xavier Defrang

Suppose you have a POP3 mailbox somewhere, perhaps on a slow connection, and need to

examine messages, and perhaps mark them for deletion, in an interactive way. Perhaps you're

behind a slow Internet link and don't want to wait for that funny 10-MB MPEG movie that you

already received twice yesterday to be fully downloaded before you can read your mail. Or maybe

there's a peculiar malformed message that is hanging your MUA. This issue is best tackled

interactively, but you need a helping script to let you examine some data about each message and

determine which messages should be removed.

Instead of telneting to your POP server and trying to remember the POP3 protocol commands (or

hoping that the server implements

help

), you can use the small script shown in Example 10-3

inspect your mailbox and do some cleaning. Basically, Python's standard POP3 module,

poplib

remembers the protocol commands on your behalf, and this script helps you use them

appropriately.

Example 10-3

uses the

poplib

module to connect to your mailbox. It then prompts you about

what to do with each undelivered message. You can view the top of the message, leave it on the

server, or mark it for deletion. No particular tricks or hacks are used in this piece of code: it's a

simple example of

poplib

usage. In addition to being practically useful in emergencies, it can

show how

poplib

works. The

poplib.POP3

call returns an object that is ready for

connection to a POP3 server specified as its argument. We complete the connection by calling the

user

and

pass_

methods to specify a user ID and password. Note the trailing underscore in

pass_

: this method could not be called

pass

because that is a Python keyword (the do-nothing

statement), and by convention, such issues are always solved by appending an underscore to the

identifier.

After connection, we keep working with methods of the

pop

object. The

stat

method returns

the number of messages and the total size of the mailbox in bytes. The

top

method takes a

message-number argument and returns information about that message, as well as the message

itself as a list of lines (you can specify a second argument N to ensure that no more than N lines

are returned). The

dele

method also takes a message-number argument and deletes that message

from the mailbox (without renumbering all other messages). When we're done, we call the

quit

method. If you're familiar with the POP3 protocol, you'll notice the close correspondence between

these methods and the POP3 commands.

Example 10-3. Interactive POP3 mailbox inspector

# Helper interactive script to clean POP3 mailboxes from

malformed mails that

# hangs MUA's, messages that are too large, etc.

# Iterates over nonretrieved mails, prints selected elements

from the headers,

# and prompts interactively about whether each message

should be deleted

import sys, getpass, poplib, re

# Change according to your needs

Secure pdf remove - C# PDF Digital Signature Library: add, remove, update PDF digital signatures in C#.net, ASP.NET, MVC, WPF

Help to Improve the Security of Your PDF File by Adding Digital Signatures

cannot print pdf security; decrypt pdf without password

Secure pdf remove - VB.NET PDF Digital Signature Library: add, remove, update PDF digital signatures in vb.net, ASP.NET, MVC, WPF

Guide VB.NET Programmers to Improve the Security of Your PDF File by Adding Digital Signatures

change security settings on pdf; change pdf security settings reader

POPHOST = "pop.domain.com"

POPUSER = "jdoe"

POPPASS = ""

# The number of message body lines to retrieve

MAXLINES = 10

HEADERS = "From To Subject".split( )

args = len(sys.argv)

if args>1: POPHOST = sys.argv[1]

if args>2: POPUSER = sys.argv[2]

if args>3: POPPASS = sys.argv[3]

if args>4: MAXLINES= int(sys.argv[4])

if args>5: HEADERS = sys.argv[5:]

# Headers you're actually interested in

rx_headers = re.compile('|'.join(headers), re.IGNORECASE)

try:

# Connect to the POPer and identify user

pop = poplib.POP3(POPHOST)

pop.user(POPUSER)

if not POPPASS or POPPASS=='=':

# If no password was supplied, ask for it

POPPASS = getpass.getpass("Password for %s@%s:" %

(POPUSER, POPHOST))

# Authenticate user

pop.pass_(POPPASS)

# Get some general information (msg_count, box_size)

stat = pop.stat( )

# Print some useless information

print "Logged in as %s@%s" % (POPUSER, POPHOST)

print "Status: %d message(s), %d bytes" % stat

bye = 0

count_del = 0

for n in range(stat[0]):

msgnum = n+1

# Retrieve headers

response, lines, bytes = pop.top(msgnum, MAXLINES)

# Print message info and headers you're interested

print "Message %d (%d bytes)" % (msgnum, bytes)

print "-" * 30

print "\n".join(filter(rx_headers.match, lines))

print "-" * 30

Online Remove password from protected PDF file

Remove password from protected PDF file. You can receive the unlocked PDF by simply clicking download and you a file it is transmitted using a secure connection

change security on pdf; add security to pdf

C# PDF Library SDK to view, edit, convert, process PDF file for C#

XDoc.PDF SDK provides users secure methods to protect PDF document. C# users can set password to PDF and set PDF file permissions to protect PDF document.

pdf password encryption; decrypt pdf password online

# Input loop

while 1:

k = raw_input("(d=delete, s=skip, v=view, q=quit)

What?")

k = k[:1].lower( )

if k == 'd':

# Mark message for deletion

k = raw_input("Delete message %d? (y/n)" %

msgnum)

if k in "yY":

pop.dele(msgnum)

print "Message %d marked for deletion" %

msgnum

count_del += 1

break

elif k == 's':

print "Message %d left on server" % msgnum

break

elif k == 'v':

print "-" * 30

print "\n".join(lines)

print "-" * 30

elif k == 'q':

bye = 1

break

# Time to say goodbye?

if bye:

print "Bye"

break

# Summary

print "Deleting %d message(s) in mailbox %s@%s" % (

count_del, POPUSER, POPHOST)

# Commit operations and disconnect from server

print "Closing POP3 session"

pop.quit( )

except poplib.error_proto, detail:

# Fancy error handling

print "POP3 Protocol Error:", detail

10.14.1 See Also

Documentation for the standard library modules

poplib

and

getpass

in the Library

Reference; the POP protocol is described in RFC 1939 (http://www.ietf.org/rfc/rfc1939.txt

C# HTML5 PDF Viewer SDK to view, annotate, create and convert PDF

C#.NET: Edit PDF Password in ASP.NET. RaterEdge HTML5 PDF Editor also provides C#.NET users secure solutions for PDF document protection.

pdf security settings; decrypt pdf file

C# Create PDF Library SDK to convert PDF from other file formats

& thread-safe .NET solution which provides a reliable and quick approach for C# developers to create a highly-secure and industry-standard PDF document file.

pdf unlock; create pdf the security level is set to high

10.15 Module: Watching for New IMAP Mail Using a GUI

Credit: Brent Burley

Suppose you need to poll an IMAP inbox for unread messages and display the sender and subject

in a scrollable window using Tkinter. The key functionality you need is in the standard Python

module

imaplib

, with some help from the

rfc822

module. Example 10-4

reads the server

name, user, and password from the ~/.imap file. They must be all on one line, separated by spaces.

The hard (and interesting) part of developing this program was figuring out how to get the IMAP

part working, which took a fair bit of investigating. The most productive approach to

understanding the IMAP protocol proved to be talking to the IMAP server directly from a Python

interactive session to see what it returned:

>>> import imaplib

>>> M = imaplib.IMAP4(imap_server)

>>> M.login(imap_user, imap_password)

('OK', ['LOGIN complete'])

>>> M.select(readonly=1)

('OK', ['8'])

>>> M.search(None, '(UNSEEN UNDELETED)')

('OK', ['8'])

>>> M.fetch(8, '(BODY[HEADER.FIELDS (SUBJECT FROM)])')

('OK', [('8 (BODY[HEADER.FIELDS (SUBJECT FROM)] {71}', 'From:

John Doe

<John.Doe@nowhere.com>

Subject: test

message

'), ')'])

Interactive exploration is so simple with Python because of excellent interactive environments

such as the standard interactive session (with readline and completion) or IDEs such as IDLE. As

such, it is often the best way to clarify one's doubts or any ambiguities one may find in the

documentation.

Example 10-4. Watching for new IMAP mail with a GUI

import imaplib, string, sys, os, re, rfc822

from Tkinter import *

PollInterval = 60 # seconds

def getimapaccount( ):

try:

f = open(os.path.expanduser('~/.imap'))

except IOError, e:

print 'Unable to open ~/.imap: ', e

sys.exit(1)

global imap_server, imap_user, imap_password

try:

imap_server, imap_user, imap_password =

string.split(f.readline( ))

Online Change your PDF file Permission Settings

can receive the locked PDF by simply clicking download and you are good to go!. Web Security. When you upload a file it is transmitted using a secure connection

change security settings on pdf; change pdf security settings

PDF Image Viewer| What is PDF

information; Royalty-free to develop PDF compatible software; Open standard for more secure, dependable electronic information exchange.

convert secure webpage to pdf; create secure pdf online

except ValueError:

print 'Invalid data in ~/.imap'

sys.exit(1)

f.close( )

class msg: # a file-like object for passing a string to

rfc822.Message

def _ _init_ _(self, text):

self.lines = string.split(text, '\015\012')

self.lines.reverse( )

def readline(self):

try: return self.lines.pop( ) + '\n'

except: return ''

class Mailwatcher(Frame):

def _ _init_ _(self, master=None):

Frame._ _init_ _(self, master)

self.pack(side=TOP, expand=YES, fill=BOTH)

self.scroll = Scrollbar(self)

self.list = Listbox(self, font='7x13',

yscrollcommand=self.scroll.set,

setgrid=1, height=6, width=80)

self.scroll.configure(command=self.list.yview)

self.scroll.pack(side=LEFT, fill=BOTH)

self.list.pack(side=LEFT, expand=YES, fill=BOTH)

def getmail(self):

self.after(1000*PollInterval, self.getmail)

self.list.delete(0,END)

try:

M = imaplib.IMAP4(imap_server)

M.login(imap_user, imap_password)

except Exception, e:

self.list.insert(END, 'IMAP login error: ', e)

return

try:

result, message = M.select(readonly=1)

if result != 'OK':

raise Exception, message

typ, data = M.search(None, '(UNSEEN UNDELETED)')

for num in string.split(data[0]):

try:

f = M.fetch(num, '(BODY[HEADER.FIELDS

(SUBJECT FROM)])')

m = rfc822.Message(msg(f[1][0][1]), 0)

subject = m['subject']

except KeyError:

f = M.fetch(num, '(BODY[HEADER.FIELDS

(FROM)])')

m = rfc822.Message(msg(f[1][0][1]), 0)

subject = '(no subject)'

fromaddr = m.getaddr('from')

C# PowerPoint - PowerPoint Creating in C#.NET

SDK for .NET, is a robust & thread-safe .NET solution which provides a reliable and quick approach for C# developers to create a highly-secure and industry

decrypt pdf password online; creating secure pdf files

C# Word - Word Creating in C#.NET

Word SDK for .NET, is a robust & thread-safe .NET solution which provides a reliable and quick approach for C# developers to create a highly-secure and industry

create secure pdf; pdf security remover

if fromaddr[0] == "": n = fromaddr[1]

else: n = fromaddr[0]

text = '%-20.20s %s' % (n, subject)

self.list.insert(END, text)

len = self.list.size( )

if len > 0: self.list.see(len-1)

except Exception, e:

self.list.delete(0,END)

print sys.exc_info( )

self.list.insert(END, 'IMAP read error: ', e)

M.logout( )

if _ _name_ _=='_ _main_ _':

getimapaccount( )

root = Tk(className='mailwatcher')

root.title('mailwatcher')

mw = Mailwatcher(root)

mw.getmail( )

mw.mainloop( )

10.15.1 See Also

Documentation for the standard library modules

imaplib

and

rfc822

in the Library

Reference; information about Tkinter can be obtained from a variety of sources, such as

Pythonware's An Introduction to Tkinter, by Fredrik Lundh (http://www.pythonware.com/library

New Mexico Tech's Tkinter reference (http://www.nmt.edu/tcc/help/lang/python/docs.html

), and

various books; the IMAP protocol is described in RFC 2060 (http://www.ietf.org/rfc/rfc1939.txt

C# Word - Word Create or Build in C#.NET

a robust & thread-safe .NET solution which provides a reliable and quick approach for C# developers to create a highly-secure and industry Create Word From PDF.

copy locked pdf; add security to pdf in reader

RasterEdge.com General FAQs for Products

not the product end user, please copy and email the secure download link are dedicated to provide powerful & profession imaging controls, PDF document, image

pdf encryption; convert locked pdf to word doc

Chapter 11. Web Programming

Section 11.1. Introduction

Section 11.2. Testing Whether CGI Is Working

Section 11.3. Writing a CGI Script

Section 11.4. Using a Simple Dictionary for CGI Parameters

Section 11.5. Handling URLs Within a CGI Script

Section 11.6. Resuming the HTTP Download of a File

Section 11.7. Stripping Dangerous Tags and Javascript from HTML

Section 11.8. Running a Servlet with Jython

Section 11.9. Accessing Netscape Cookie Information

Section 11.10. Finding an Internet Explorer Cookie

Section 11.11. Module: Fetching Latitude/Longitude Data from the Web

11.1 Introduction

Credit: Andy McKay

The Web has been a key technology for many years now, and it has become unusual to develop an

application that doesn't involve some aspects of the Web. From showing a help file in a browser to

using web services, the Web has become an integral part of most applications.

I came to Python through a rather tortuous path of ASP, then Perl, some Zope, and then Python.

Looking back, it seems strange that I didn't find Python earlier, but the dominance of Perl and

ASP in this area makes it hard for new developers to see the advantages of Python shining through

all the other languages.

Unsurprisingly, Python is an excellent language for web development, and, as a "batteries

included" language, Python comes with most of the modules you will need. The inclusion of

xmlrpclib

in Python 2.2 has made the standard libraries even more useful. One of the

modules I often use is

urllib

, which demonstrates the power of a simple, well-designed

module—saving a file from the Web in two lines (using

urlretrieve

) is easy. The

cgi

module is another example of a module that has enough to work with, but not too much to make

the script too slow and bloated.

Compared to other languages, Python seems to have an unusually large number of application

servers and templating languages. While it's easy to develop anything for the Web in Python, it

would be peculiar to do so without first looking at the application servers available. Rather than

continually recreating dynamic pages and scripts, the community has taken on the task of building

these application servers to allow other users to create the content in easy-to-use templating

systems.

Zope is the most well-known product in the space and provides an object-oriented interface to web

publishing. With features too numerous to mention, it allows a robust and powerful object-

publishing environment. Quixote and WebWare are two other application servers with similar,

highly modular designs. These can be a real help to the overworked web developer who needs to

reuse components and give other users the ability to create web sites.

There are times when an application server is just too much and a simple CGI script is all you

need. The first recipe in this chapter, Recipe 11.2

, is all you need to make sure your web server

and Python CGI scripting setup are working correctly. Writing a CGI script doesn't get much

simpler than this, although, as the recipe's discussion points out, you could use the

cgi.test

function to make it even shorter.

Another common task is the parsing of HTML, either on your own site or on other web sites.

Parsing HTML tags correctly is not as simple as many developers first think, as they optimistically

assume a few regular expressions or string searches will see them through. While such approaches

will work for parsing data from other sites, they don't provide enough security to ensure that

incoming HTML contains no malicious tags. Recipe 11.7

is a good example of using

sgmllib

to parse incoming data and strip any offending JavaScript. Most web developers create more than

just dynamic web pages, and there are many relevant, useful recipes in other chapters that describe

parsing XML, reading network resources and systems administration, for example.

11.2 Testing Whether CGI Is Working

Credit: Jeff Bauer

11.2.1 Problem

You want a simple CGI program to use as a starting point for your own CGI programming or to

test if your setup is functioning properly.

11.2.2 Solution

The

cgi

module is normally used in Python CGI programming, but here we use only its

escape

function to ensure that the value of an environment variable doesn't accidentally look to

the browser as HTML markup. We do all of the real work ourselves:

#!/usr/local/bin/python

print "Content-type: text/html"

print "<html><head><title>Situation

snapshot</title></head><body><pre>"

import sys

sys.stderr = sys.stdout

import os

from cgi import escape

print "<strong>Python %s</strong>" % sys.version

keys = os.environ.keys( )

keys.sort( )

for k in keys:

print "%s\t%s" % (escape(k), escape(os.environ[k]))

print "</pre></body></html>"

11.2.3 Discussion

The Common Gateway Interface (CGI) is a protocol that specifies how a web server runs a

separate program (often known as a CGI script) that generates a web page dynamically. The

protocol specifies how the server provides input and environment data to the script and how the

script generates output in return. You can use any language to write your CGI scripts, and Python

is well-suited for the task.

This recipe is a simple CGI program that displays the current version of Python and the

environment values. CGI programmers should always have some simple code handy to drop into

their cgi-bin directories. You should run this script before wasting time slogging through your

Apache configuration files (or whatever other web server you want to use for CGI work). Of

course,

cgi.test

does all this and more, but it may, in fact, do too much. It does so much, and

so much is hidden inside

cgi

's innards, that it's hard to tweak it to reproduce whatever specific

problems you may be encountering in true scripts. Tweaking the program in this recipe, on the

other hand, is very easy, since it's such a simple program, and all the parts are exposed.

Besides, this little script is already quite instructive in its own way. The starting line,

#!/usr/local/bin/python

, must give the absolute path to the Python interpreter with

which you want to run your CGI scripts, so you may need to edit it accordingly. A popular

solution for non-CGI scripts is to have a first line (the so-called "shebang line") that looks

something like this:

#!/usr/bin/env python

However, this puts you at the mercy of the

PATH

environment setting, since it runs the first

program named

python

it finds on the

PATH

, and that probably is not what you want under

CGI, where you don't fully control the environment. Incidentally, many web servers implement

the shebang line even when you run them under non-Unix systems, so that, for CGI use

specifically, it's not unusual to see Python scripts on Windows start with a first line such as:

#!c:/python22/python.exe

Another issue you may be contemplating is why the

import

statements are not right at the start

of the script, as is the usual Python style, but are preceded by a few

statements. The

reason is that

import

could fail if the Python installation is terribly misconfigured. In case of

failure, Python will emit diagnostics to standard error (which is typically directed to your web

server logs, depending, of course, on how you set up and configured your web server), and

nothing will go to standard output. The CGI standard demands that all output be on standard

output, so, we first ensure that a minimal quantity of output will display a result to a visiting

browser. Then, assuming that

import sys

succeeds (if it fails, the whole installation and

configuration is so badly broken that there's very little you can do about it!), you immediately

make the following assignment:

sys.stderr = sys.stdout

This ensures that error output will also go to standard output, and you'll have a chance to see it in

the visiting browser. You can perform other

import

operations or do further work in the script

only when this is done. In Python 2.2, getting useful tracebacks for errors in CGI scripts is much

simpler. Simply add the following at the start of your script:

import cgitb; cgitb.enable()

and the new standard module

cgitb

takes care of the rest

Just about all known browsers let you get away with skipping most of the HTML tags that this

script outputs, but why skimp on correctness, relying on the browser to patch your holes? It costs

little to emit correct HMTL, so you should get into the habit of doing things right, when the cost is

so modest.

11.2.4 See Also

Documentation of the standard library module

cgi

in the Library Reference; a basic introduction

to the CGI protocol is available at http://hoohoo.ncsa.uiuc.edu/cgi/overview.html

Documents you may be interested

convert pdf to image asp.net c# : Secure pdf remove Library software class asp.net winforms wpf ajax O'Reilly%20-%20Python%20Cookbook44-part1472