CS141 Final Project- An Online Forum Solution

You have been provided with 4 files:
• Forum_Page.py: a skeleton file for the class definition with some methods completed and other methods for you to fill in
• words.txt: a text file containing words that will be used to auto-generate usernames (see further details in project description)
• Final_Project_Main.py: a skeleton file for your main program
• Forum_Viewer.py: a file to generate an optional visualization of your Forum_Page class

How the Forum_Page works
Users are also able to indicate whether they like or dislike a post by voting. Votes always have a value of 1, so an upvote means adding one point to the vote total, a downvote means subtracting one point from the vote total.
To simplify object construction, we are not allowing users to edit posts after they are created or to reply to posts. The only actions they can take are to add posts, delete posts (as described above), and vote on posts.

Forum_Page Class Data
Your Forum_Page class will store the following data.
• A name for the page. When the object is created, this is a string specified by the user. It will not change after it is created in the constructor.
• A list of words used to create anonymous usernames. When the object is created, this is loaded from the file words.txt (provided for you) and is stored as a list,i.e, it is the text from the file listed as individual words. It will not change after it is created in the constructor.
This is what the Data Frame looks like with a few entries:

The ... you are seeing represents further text that is too long to display.
Some advice for working with a Pandas data frame:
• You can add rows to a data frame using the .loc attribute:

df.loc['new_row_name '] = [col1_info, col2_info, col3_info, etc.]

• If you want to look up things in the data frame, use the loc attribute:

df.loc['row _name'] gives a Series containing the information associated with the row name.

df.loc['row _name', 'column _name'] will give you the information from a single cell.

• You can access the index using: df.index

• Remember that every column in a data frame is a Series. Series have many useful methods. For example, you can get the maximum value by the calling the .max() method.

• The easiest way to find out how many rows are in a data frame is to use the built in function len. Use it the same way you would with any other object.

• The in operator works with columns in the data frame, for example you can ask if a value is in a column like this: if value in df['column _name']

• You can check if a value is np.nan by using: pd.isnull(value) – this assumes pandas is imported as pd. Check for a whole Series using the .isnull() or .notnull() methods.

It will save you a lot of time and effort to use this advice as opposed to searching the internet for ways to to do these things. That often leads down a complicated rabbit hole.
Part 1: Forum_Page Class Methods
Your Forum_Page class will implement a variety of methods that allow modification of and access to the internal data. Some of these are already written for you, and you are not permitted to change them, so please read carefully.
Methods written for you
• Constructor
This takes no arguments. It stores the name, and creates the list object that holds the words for the anonymous usernames, and the empty Data Frame that will hold the post information. The constructor has already been written for you. DO NOT CHANGE IT! You need to understand what it is doing and what the attributes it creates correspond to (see above).
• __process
The private method __process takes one argument, filename, a string that represents a filename. For example, filename could be 'words.txt'. This method assumes that the file has one word per line. The method returns a list of words. This method is called by the constructor in the code given to you. It should not be called anywhere else in your class definition.
• __exists
The private method __exists takes one argument, title, a string that represents a post title. The method returns a boolean: True if the title is in the Data Frame, False if it is not. You will need to use this method in your other methods, and you MUST use this method where appropriate as opposed to repeating code from it.
• checker
The public method checker is a tool for you to use while programming. It returns a copy of the internal data frame that you can use for debugging purposes. It should not be called by any of your other methods.
• get_name

The public method get_name returns the name of the Forum Page that is stored in the object.

Methods you need to write
We expect your method implementations to reflect what you have learned about writing concise, logical code this semester. There are some suggestions about this in the method descriptions.
You will fill in your methods in the skeleton file Forum_Post.py provided. Your method implementations will be tested using a series of test cases, so be sure to test them thoroughly.
• __generate_anon
The private method __generate_anon generates anonymous usernames using the list of words created in the constructor. It takes no arguments. Usernames are constructed as follows:
o Select two unique words randomly from the list of words, e.g., harmonious and turtle, unique means that you cannot select the same word twice
o Select two random digits between 0 and 9 inclusive, e.g. 8 and 4, digits DO NOT need to be unique (this means you could pick 8 and 8, or 4 and 4, etc.)
o The anonymous username is the first word, an underscore, the second word, an underscore and then the digits, like this: harmonious_turtle_84
o Check if this username already exists (i.e. it has been used for a post previously). If it does, generate a new one. Keep generating a new random username until you get one that hasn’t already been used. o The method returns the username
There are 20 words and 10 digits, so creating the usernames this way allows for 38,000 possibilities! We shouldn’t need more than that. If you are stuck on how to get unique words, a quick look at the documentation for the random module should answer your questions: https://docs.python.org/3/library/random.html

• add_post
The public method add_post allows a user to add a post to the Forum_Page. It takes two required arguments: title, a string that is the title for a post, and post, a string that is the text of the post. It also takes the optional argument author: the user can provide a string to be used as the author for the post. Here’s an example of what these arguments might be: title: 'This is a POST'
post: 'This is the actual text of the post, where I talk about my opinion on a thing. For example, sometimes I’m very annoyed by fonts that have uneven kerning. They make writing up code with indentation that aligns very difficult' author: 'a_turtle'
Here is how the method works:
o If the user did not provide a value for author generate a username using one of your methods (hint, look at the previous page)
o As long as the title hasn’t already been used (hint: use one of the methods), add a row to the data frame for this new post, remember, the title should be the index; if the title has already been used, do nothing
• delete_post
The public method delete_post allows the user to delete a post according to the rules given in the introduction and repeated below. It takes one required argument: title, a string that is the title for the post to delete. Here is how the method works:
o Make sure that the post exists in the data frame (hint: use one of the methods); if it doesn’t exist then do nothing
o Set the author and text (the actual post) to missing, the value for the title and number of votes should be left as they are

• vote_post
The public method vote_post takes one required argument: title, a string that indicates the title of the post being voted on. The optional argument up determines whether the vote is an upvote (+1) or a downvote (-1). True corresponds to an upvote, False corresponds to a downvote. Here is how the method works:
o Make sure that the post 1) exists in the data frame (hint: use one of the methods), and 2) is available to be voted on – deleted posts cannot receive votes. If the post doesn’t meet these criteria, do nothing. o Add or subtract from the vote total accordingly
For example, if a post has 10 votes and up is True, the post would then have 11 votes.

• top_voted
• get_titles
The public method get_titles returns a list that contains the titles of all of the posts in the data frame. This method takes no arguments. Make sure that your method returns a list.
Note that this method does NOT modify the internal data frame. It just extracts information from it. Do not over-complicate this. You can write this method in one line.
• get_post_info
Note that this method does NOT modify the internal data frame. It just extracts information from it. Do not over-complicate this. You can write this method in a few lines.
• __str__ method
The __str__ method returns a string that tells how many active posts there are on the forum page. An active post is a post that has not been deleted. It also includes the name of the Forum_Page that is stored in the object. The string returned by this method should look something like:
100 active posts on name_of_Forum_Page
For example:
100 active posts on Turtle Central
The number 100 here is just an example. The number filled in will be the actual number of active posts. If you are stuck on how to count active posts, consider this: how do we identify posts that are active (or inactive)? Make a new data frame that contains just the active ones. Then count how many there are.
Part 2: Creating and using a Forum_Page Object
You will write a main program that makes use of your Forum_Page class. Your code for this part of the project goes in the file Final_Project_Main.py. You have been given a skeleton file with the correct import lines. Your code should be concise.
Your main program will carry out the following operations. All of these are achieved by creating a single Forum_Page. You will call methods on the object to meet these goals, adding in other programming structures as needed. If you are repeating code that appears in your methods in the main program, something has probably gone wrong.
• Create a Forum_Page object called CSCI_140
• You have been given a list of 5 titles and a list of 5 post texts. The first item in the title list goes with the first item in the post text list and so on. Use these lists to add 5 anonymous author posts to the Forum_Page; your code should be as efficient as possible, think about how to get the matched items from both lists most concisely.
• Upvote the post titled Final_Project 3 times
• Print out the top-voted post(s)
• Delete the post titled Potato_Recipe
• Print out a list of all of the post titles in the Forum_Page Object
• Print out a string representation of the Forum_Page Object

Please be aware that this main program does not test all of your methods and doesn’t thoroughly test most of them. Test your code thoroughly. Test beyond the main program and the testing script. Try to break all of your methods.



Optional: Visualizing the Forum_Page Interface

This section is completely optional. Whether you complete it or not has no bearing on your ability to complete the project and test your code. It is here for those of you who are interested and is kind of fun.
you can run the visualization can break your Anaconda installation completely.

The file Forum_Viewer.py contains code to generate an interactive window that represents the forum page. In order to run this file, you must do the following:
• Save Forum_Viewer.py, your completed Forum_Page.py, and the word.txt file all in the same directory (folder).
• Navigate to the directory from the command line (Terminal/Powershell)
• In your terminal type:
python Forum_Viewer.py
When you launch the Forum_Viewer, you should see an interface that looks like this:


If you click on Add post, it will bring up a dialog box where you can enter the Title, Author, and the Post. If you leave the author blank, it will automatically generate one...as long as your add_post method is written correctly. Once you add a post, it will appear in the window on the left. Click on the post name to see full information:


You can only upvote or downvote a post once per view. You’ll see the buttons grey out after you do so. You’ll have to select it again to vote again.

SUBMISSION EXPECTATIONS
Because the name of the class, methods, and files must be exactly as specified in order for our testing to work, we have provided skeleton files for you to fill in. Be certain not to change any names, and do not modify the numbers of parameters for each specified method. We expect your code to be efficient and to make use of internal methods as needed as opposed to repeating code from these methods.
Forum_Post.py: The skeleton file attached to this project, but with your implementations added. The file must contain only the methods provided and you must not change their names. You should fill in the parameter lists where indicated. Do not include any additional code in this file.
Final_Project_Main.py: The skeleton file attached to this project, but with your implementation added. The file must contain only the functionality for the main program described in the instructions.
Please do not submit words.txt or Forum_Viewer with your project.

POINT VALUES AND GRADING RUBRIC
Methods:
-add_post: 4 pts
-delete_post: 3.5 pts
-vote_post: 4 pts
-generate_anon: 3 pts
-top_voted: 2 pts
-get_post_info: 1.5 pts
-get_titles: 1.5 pts
-__str__: 2.5 pts
Main program: 3 pts



Grade Level Execution Correctness and Algorithms Formatting Style and References
Inputs and outputs formatted as per
Code correctly implements all Code uses current structures and
the specification both in terms of
algorithms, passes all test cases modules discussed in class;
A (with possible exception of meaningful variable names;
requires no manual intervention formatting issues (spacing,
extremely rare case), and meets commented as appropriate; any
punctuation, etc.); correct file
all required functionality references used cited in write-up
formats and names
Code correctly implements all the specification both in terms of discussed in class with minor
require minimal manual algorithms, meets all required content and type, some formatting additions from outside sources (e.g.
import line or copy-paste errors, or minor, rare test cases string text), correct file formats and variable names meaningful;
removal of input or print lines
names commented as appropriate
Code contains logical errors and
Code does not execute without fails subset of both rare and Code uses some structures and
minor manual intervention such as common test cases, overall Inputs and outputs have major modules discussed in class but largely
C correcting indentation or algorithmic structure reflects formatting issues, files incorrectly taken from outside sources with
terminating parentheses or a single required functionality but named but file formats correct appropriate citations; most variable
syntax error implementation does not meet names meaningful standards
Code does not execute without
major manual intervention such as Code contains major logical errors Code uses structures and modules
Inputs and outputs have major changing variable names, and fails majority of test cases, largely taken from outside sources
D formatting issues, files incorrectly
correcting multiple syntax errors, lack of cohesive algorithmic with citations; variable names and
named but file formats correct
algorithmic changes (e.g. infinite structure, minimal functionality code structure hard to decipher loops)

Code requires extensive manual
F
intervention to execute


Code fails all test cases and has no functionality to solve the proposed problem
Inputs and outputs have major formatting issues, files in incorrect formats which cannot be graded Code uses structures and modules from outside sources only with no citations; variable names and code structure hard to decipher; code written in other programming languages or Python 2.7