What is the best way to write to a file in Ruby?

General Discussions
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1

What is the best way to write to a file in Ruby?

I need to read data from a database and save it into a text file. How can I achieve this in Ruby? Does Ruby provide any built-in file management system for this purpose?

2

Ruby provides built-in methods for file management. The simplest way to write to a file in Ruby is by using File.open with the write mode:

File.open("output.txt", "w") do |file|
  file.write("Hello, this is a test!")
end

This creates (or overwrites) a file named output.txt and writes the string inside it. The do |file| … end block ensures that the file is closed automatically after writing, which is a good practice to prevent memory leaks or file corruption.

3

That’s a solid approach! But if you want to append data instead of overwriting the file, you can use ‘a’ mode instead of ‘w’:

File.open("output.txt", "a") do |file|
  file.puts("This line gets appended instead of replacing previous content.")
end

Additionally, it’s good practice to handle potential file errors using begin-rescue blocks:

begin
  File.open("output.txt", "w") { |file| file.puts("Writing safely!") }
rescue IOError => e
  puts "File write failed: #{e.message}"
end

This ensures that your program doesn’t crash if something goes wrong, like insufficient permissions or disk space issues."

4

Using Ruby’s File.write for Simplicity

Both methods are great! But for a quick and simple way to write to a file in Ruby, you can use File.write, which is a one-liner:

File.write("output.txt", "This will overwrite any existing content.")

you want to append instead of overwriting, you can pass the mode as a third argument:

File.write("output.txt", "This gets appended!", mode: "a")

This approach is useful when you don’t need advanced file handling and just want a straightforward way to write data."