Get File Content

Now that we have a function that can get the contents of a directory, we need one that can get the contents of a file. Again, we'll just return the file contents as a string, or an error string if something went wrong.

As always, we'll safely scope the function to a specific working directory.

Assignment

Create a new file in your functions directory (e.g., functions/get_file_content.py) and define the following function in it:
```
def get_file_content(working_directory, file_path):
```

If the file_path is outside the working_directory, return a string with an error:

f'Error: Cannot read "{file_path}" as it is outside the permitted working directory'

If the file_path is not a file, again, return an error string:

f'Error: File not found or is not a regular file: "{file_path}"'

Read the file and return its contents as a string.
- I'll list some useful standard library functions in the Tips section below.
- If the file is longer than 10000 characters, truncate it to 10000, and append this message to the end [...File "{file_path}" truncated at 10000 characters].
- Instead of hard-coding the 10000 character limit, I stored it in a config.py file.

We don't want to accidentally read a gigantic file and send all that data to the LLM... that's a good way to burn through our token limits.

If any errors are raised by the standard library functions, catch them and instead return a string describing the error. Always prefix errors with Error:.
Create a new lorem.txt file in the calculator directory. Fill it with at least 20,000 characters of lorem ipsum text. You can generate some here.
Create a new test module at the root of your project, test_get_file_content.py. It should be similar in structure to the test module that you wrote for get_files_info. Start by testing get_file_content("calculator", "lorem.txt"), and ensure that it truncates properly. (You don't need to print the entire content; just check the length and the truncation message at the end.)
Once the lorem ipsum test is passing, add the following test cases, printing their outputs:
- get_file_content("calculator", "main.py")
- get_file_content("calculator", "pkg/calculator.py")
- get_file_content("calculator", "/bin/cat") (this should return an error string)
- get_file_content("calculator", "pkg/does_not_exist.py") (this should return an error string)

Run and submit the CLI tests.

Tips

os.path.abspath: Get an absolute path from a relative path
os.path.join: Join two paths together safely (handles slashes)
.startswith: Check if a string starts with a specific substring
os.path.isfile: Check if a path is a file

Example of reading up to a certain number of characters from a text file:

MAX_CHARS = 10000

with open(file_path, "r") as f:
    file_content_string = f.read(MAX_CHARS)