Build your own wc in go

Intro

I began learning Go and wanted to work on a project to enhance my skills. I discovered this build your own wc tool challenge and decided to take it on.

How to run

Make sure you have Go installed.

Then clone the repo and run make build in the root directory.

Then you can write this command:

# Without any flags will show the help message

> ./ccwc 
Usage of ./ccwc:
  -c    print the byte/s count
  -l    print the line count
  -m    print the character count
  -w    print the word count

# Show line count

> ./ccwc -l <file>
791 ./data/test.txt

# Show word count

> ./ccwc -w <file>
10859 ./data/test.txt

# Show character count

> ./ccwc -m <file>
61031 ./data/test.txt

# Show byte count

> ./ccwc -c <file>
61031 ./data/test.txt

# without any flags will show all the counts
# similar to `wc` command
> ./ccwc ./data/test.txt
791 10859 61031 ./data/test.txt

Why Dockerfile

I was curious to see what a Go project Dockerfile looks like; it turns out it's really simple.

Just build the image and run it:

docker build -t ccwc .
docker run -it ccwc # or with any flag like above

Project Structure

This section provides an overview of the purpose of the key files in this project:

• main.go: The main entry point of the application. It handles command-line arguments, processes the input file or standard input, and prints the results.
• reader.go: Contains the CountLinesWordsBytes function, which counts the number of lines, words, and bytes in a given file. This function does the most of the work.
• stdin_util.go: Contains the StdinUtil function, which opens the file provided as a command-line argument or returns the standard input if no file is specified.
• stat.go: Contains the Stat function, which retrieves and returns the file information for a given file path, including details such as file size, permissions, and modification time. (You can use this instead of reader.go file)
• mem.go: Contains the Mem function, which returns the memory usage of the program. Just put Mem() in the beginning and end of the main function.
• reader_test.go: Contains the tests for the CountLinesWordsBytes function.

Credits

I studied other codes who have completed this challenge in Go. Here is the list:

• André Brandão
• PraveshGoyal
• Hruthik Reddy Yarala

Also I used project like lazygit and lazydocker to help me understand how to use Go in a large scale project.