go-rwfs

Golang read-write filesystem interfaces

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📝 Table of Contents

• About
• Getting Started
• Usage
• Built Using
• TODO
• Contributing
• Authors
• Acknowledgments

🧐 About

Wrapper around io.fs interfaces to support read-write operations.

Its fully compatible with the fs standard package to avoid duplicating implementations.

Why?

Golang provides a read-only filesystem and numerous IO abstractions. That's great to read files without mangling your code with OS details. For some reason the designers decided to stop there, and provided no read-write interface. If you need to write files, then you need to fallback and use concrete types such as os.File, which hardcodes the requirement to use a OS-level filesystem.

go-rwfs provides:

• a FS interface based on fs.FS with the extra method OpenFile
• a File interface based on fs.File with writer interfaces from io

This means those interfaces are a drop-in replacement for any use-cases of the fs package where you now need write access as well.

🏁 Getting Started

Fetch the package:

go get github.com/wwmoraes/go-rwfs

Now you're good to Go 😉

🔧 Running the tests

Clone the repository then use make coverage to run both unit and integration tests.

🎈 Usage

The package comes with a concrete implementation for the OS filesystem, similar to how the standard Golang distribution provides os.DirFS:

package main

import "github.com/wwmoraes/go-rwfs"

// for brevity's sake there's no error checking, please forgive me ;)
func main() {
  // create a sample folder and file with plain OS methods
  os.Mkdir("foo", 0750)

  osFile, _ := os.Create("foo/bar.txt")
  osFile.Close()

  // create a RWFS on the new folder
  fsys := rwfs.OSDirFS("foo")

  // read-only usage, same as with fs.FS
  entries, _ := fs.ReadDir(fsys, "/")

  for _, entry := range entries {
    fmt.Println("file found:", entry.Name())
  }

  // read-write usage
  fd, _ := fsys.OpenFile("bar.txt", os.O_WRONLY|os.O_TRUNC, 0640)
  defer fd.Close()

  fd.WriteString("hello from rwfs!")
}

🔧 Built Using

• Golang - Base language

🧑‍💻 Authors

• @wwmoraes - Idea & Initial work

🎉 Acknowledgements

• Golang team for providing the fs and io interfaces