Home | Schedule & Readings | Links & Resources

Radical Software

LCST 2234, Fall 2021 (CRN 9430)
Rory Solomon

Project 1, Tutorial 1: Setting up your Twitter bot

Project setup.

Setup some folders for your work this semester. Create a folder called "Radical Software - Fall 2021", if you don't already have something like this. Within this, create a folder for this project called "Project 1".
Access the command line interface (CLI) on your computer.

On Mac, you can do this with Terminal, which you can find via a Spotlight Search (typing COMMAND-SPACE, i.e. ⌘-SPACE), or by opening Finder, clicking Applications, double-clicking on Utilities, and then double-clicking Terminal.

On Windows, you will need to install Cygwin and then open the Cygwin shell.

After class, make sure to watch the two videos that I have posted on the Schedule page under Week 1 for some additional background on the CLI, its history and how to use it,
Explore the command line, and find the place where you'll be working on this project.

Type the following commands at the command prompt, one line at a time, pressing enter after each one. Think about what you are seeing. Copy/paste these commands and their output into your Lab Notebook with some commentary. Note: You should not type the dollar sign $. I put that there as an indicator of your command prompt, and where the cursor is, where you should type. Your command prompt may be a percentage sign (%), and if so, that is perfectly fine.
```
$ pwd
$ ls
```
pwd stands for "print working directory" and it displays the folder that the command line interface is "currently" in. Just like how in Finder, you can be in different folders to do work like adding, removing, and editing files, in the command line, you also need to be "in" a currently active folder. In a command line context, we refer to folders as directories — these terms are synonymous. So pwd shows you which directory you are currently "working" in.

ls signifies "list" and it displays all the files and folders that are in your current directory. The names of the files and folders that you see here may look familiar: they are the same files that you would see if you opened this directory (folder) in Finder (Mac) or Explorer (Windows).

Now let's make sure your computer has the tools installed that you'll be using. Again, type this commands in, one line at a time, pressing enter after each, and copy/pasting the results into your Lab Notebook.
```
$ which python
$ ls -l COPY-PASTE THE OUTPUT OF THE PREVIOUS COMMAND HERE	  
$ which pip
$ which git
```
You don't need to type these commands every time you work. They are just a way for us to explore your computer and the tools that are already installed on it. It will help me understand how your computer is configured and may be useful later for debugging. So please include all this in your Lab Notebook.
Change your folder from within the command line

The way you do this is with the cd command, which stands for "change directory."

Type cd on the command line but don't hit enter yet. (Note that this is "cd" followed by a space.) Next, find the "Project 1" folder in Finder that you created above, and drag-and-drop that folder into Terminal. This should add a bunch of text to the command line. That text is called a path: it is a textual representation of the folder including its name, and the names of all folders it is contained in, going all the back to the root folder of your compter. (Very "radical" in a sense.)

You might see something like this, but yours will be a little different depending on your path — i.e., where you placed your class and project folders on your computer:
```
cd /Users/rory/Documents/Classes/Radical\ Software\ -\ Fall\ 2021/Project\ 1
```
When you see that, press enter. Now your command line is "in" your project folder. Any files that you create in the command line here will be visible in Finder. It's almost like a "behind-the-scenes" way to work with the files that you would otherwise see in your graphical user interface.

Note: Any time you want to work on this project, you will need to open the command line, and cd in to the project folder that you want to work in.
Access the starter files for this project using git and GitHub.

If you do not yet have a GitHub account, visit github.com and create one. Make sure to add your username in your Lab Notebook. I will need this to configure our class's shared GitHub resources this semester and to identify you later when you will use GitHub to submit some of your work.

Once you are logged in to GitHub, visit our class GitHub space:
https://github.com/Radical-Software-Fall-2021

Click "project-1" to go to the repository for this project. A repository is a term for a collection of source code files. I have created this repository with the code that you will need to start the project. You will be modifying this as you work on the project.

To modify this repository, you will need to make your own copy of it to work in. In git language, that is called maing a fork. To do this, click on the "Fork" button in the upper-right of the window. (If you're asked "Where should we fork project-1?" select the username you just created.) Now you have your own copy of these project files to work with.

To get started working with them, we need to download the files onto your computer. In git language, the term for this is clone. You will need to clone your new repository.

Click on the green drop-down button that says "Code". That will reveal a URL to you highlight and copy that URL, or just click the little clipboard icon. Next, go back to the command line and type git clone, then paste in your URL. For example:
```
$ git clone https://github.com/lang-student/project-2.git
```
and press enter. That will create a new directory called project-1. You should be able to see its contents in Finder (Mac) or Explorer (Windows), or by typing ls project-1. The contents of this directory should match the contents that you can see on the project page on the GitHub website.

cd into this directory so we can work on the code files that it contains:
```
$ cd project-1
```
Now let's start editing these code files!
Install a text editor.

I recommend Atom, which is available at atom.io. If you already have another text editor that you are comfortable with and that you would prefer using, feel free, but please keep in mind that my capacity to offer technical support for project work this semester will be limited to folks using Atom. I'm not able to offer detailed help for all possible platforms.

When you first open Atom it will have some introductions and things. You can close all these tabs. Now open your project. You can either click File > Open and navigate to your project-1 folder, or, you can simply drag-and-drop project-1 into Atom. Either way, you should see a sidebar with all the contents of the folder.

Look around at these various files. What do you see? Make some notes about your first impressions in your Lab Notebook.

Let's focus on main.py. Modify line 10 replacing the text in parenthesis with a string, a sequence of text in quotation marks. This will be the message that your Twitter bot will tweet. For example:
```
api.update_status("hi it's rory")
```
Save the file (click File > Save).
Run the file!

Go to the command line and type:
```
$ python app/main.py
```
You should get an error message. What does it say?
If you get an error message stating that the tweepy module is not found, that is because the Python code that I've given you depends on an external module, also known as a library: a bit of self-contained code that a developer has created to do some task, and then distributed for others to use. In this case, the tweepy library is a bit of code that makes it easy to interact with the Twitter API from within Python computer programs. If an API is a kind of interface (remember, that's what the "I" stands for) then a library like tweepy is almost a kind of interface to an interface. It offers Python functions that you can call from Python code to easily access the Twitter API. (The name "tweepy" is meant to signify that it involves Twitter plus Python.)

Let's install the tweepy library! Fortunately, I've distributed a bit of code in the project to help you do this. If you look in requirements.txt, it specifies the tweepy library. You could add other library dependencies here as well if you need to as you work on your project. Then you can easily install all of the dependencies named there by using the pip command, like this:
```
$ pip install -r requirements.txt
```
Try to run your bot again:
```
$ python app/main.py
```
You'll probably get another error. Something about authorization_tokens.py missing. Look inside main.py. On line 3 it is trying to import this module, but we haven't created it yet.

When you access Twitter yourself, you have to type in a username and password. Well when you are trying to access Twitter via a computer program, you also need to authenticate yourself (i.e., to login) but it is not wise to put usernames and passwords in code, so twitter uses these long encrypted numbers called tokens. Anyone who has these tokens could access the Twitter API and pretend to be my Twitter bot account, so it is important to keep them secret. I couldn't put them in GitHub since our GitHub repository is public. So instead I have put them into Google Drive with permissions set so only our class can access them.

You can get these authorization tokens here:

authorization_tokens.py (You will need to be signed in to your New School Google account to access.)

Create a new file in Atom (File > New). Copy/paste the contents of authorization_tokens.py into this file. Click File > Save. Make sure you save the file in the app folder of your project and name it "authorization_tokens.py".
Once you have your authorization_tokens.py file saved. Try to run your code again:
```
$ python app/main.py
```
Does it work? If you got a message that says "Done" then it probably did! Check our Twitter developer account to see if you can see your message: twitter.com/bot_ror.

If so, congratulations! You just created a basic chat bot with the Twitter API.

We'll talk about some techniques to customize this in the coming weeks.
Update your Lab Notebook with some thoughts and reflections on this exercise. Make sure to include all the things that I've mentioned above. You can find the template here:

Lab notebook template ("Hacker log") — Open this link and click File > Make a copy, or File >

You can either download that to somewhere on your computer in your preferred format (probably .docx, .odt, or .txt) and re-upload it to your Google Drive folder, or, you can create a duplicate Google Doc within Google Drive and make sure to save it to your project folder.