Use the command line to create a new directory called lab16 in your labs directory. Make sure all of the .py files that you create for this activity are in that directory.
String Strip
One of the biggest security vulnerabilities that web developers are constantly fighting is known as an SQL injection attack.. In this attack, users of a website format input in such a way that their input gets interpreted as code in the web developers systems. The easiest mechanism for preventing such an attack is to remove the offending characters before they get used in inappropriate ways.
Details
Write a function
called strip_non_alpha(offending_string) in a file
called input_sanitation.py. This function takes a string
as a parameter, and returns a copy of the input string with all
non-alphabetic characters removed.
Make sure you test your program well. How many test cases do you need? Make sure you follow all of the course's coding conventions.
Sample Test Cases
Note: Quotation marks included in output for clairly only. Your program should not output the quotation marks.
| Function Parameters | Expected Output |
|---|---|
| "Hello, World" | "HelloWorld" |
| "Scotty " | "Scotty" |
| "!@#$" | "" |
Hint
Challenge
In the real world, the true offending characters are double and single
quotes. Write a new function
called escape_strings(offending_string) that takes as
input a single string, and returns a copy of the string with all
single or double quotes "escaped". Recall that a quote can be escaped
in a string by pre-pending it with a backslash (\" or
\').
Password Generation
Passwords are possibly the most important way that individuals can ensure their own safety on the Internet. However, it is also typically the easiest thing for a hacker to figure out, or to get their hands on. This is simply because most Internet users choose incredibly weak passwords. The easiest way to get around this issue to to use a randomly generated password.
Details
Write a function called generate_password(size), which
takes a positive integers as a parameter. Your program should
return a string of lower case letters of the specified size. This
function should randomly choose the lower case letters in the
returned string.
Your program should ask the user for a password length, and print to the terminal the password you generate.
Make sure you test your program well. How many test cases do you need? Make sure you follow all of the course's coding conventions.
Example Execution
$ python3 password_generation.py How long do you want your password? 5 neolp $ python3 password_generation.py How long do you want your password? 10 wigmnhgqwn
Hint
Challenge
Even random strings of lowercase characters are pretty easy to break. A better program would randomly decide to include some uppercase letters as well. Alter your function so that it will sometimes include uppercase letters in the generated passwords. Make sure the parameter used to determine how often an uppercase character is used is well documented and easily altered.
Submission
Please show your source code and run your programs for the instructor or lab assistant. Only a programs that have perfect style and flawless functionality will be accepted as complete.