aferox

The aferox packages expands on github.com/spf13/afero by adding more afero.Fs implementations, as well as various afero.Fs utility functions.

Go Doc

containerregistry

The containerregistry package adds implementations of afero.Fs wrapping github.com/google/go-containerregistry v1.Image and v1.Layer abstractions. Currently readonly.

img, _ := image.FromFs(afero.NewMemMapFs())
fs, _ := image.ToFs(empty.Image)

layer, _ = layer.FromFs(afero.NewMemMapFs())
fs, _ := layer.ToFs(empty.Layer)

This package lives in a separate module to avoid adding a dependency on go-containerregistry to aferox.

Go Doc

go get github.com/unmango/aferox/containerregistry

github

The github package adds multiple implementations of afero.Fs for interacting with the GitHub API as if it were a filesystem. In general it can turn a GitHub url into an afero.Fs.

fs := github.NewFs(github.NewClient(nil))

file, _ := fs.Open("https://github.com/unmango")

// ["go", "thecluster", "pulumi-baremetal", ...]
file.Readdirnames(420)

This package lives in a separate module to avoid adding a dependency on go-github to aferox.

Go Doc

go get github.com/unmango/aferox/github

ignore

The ignore package adds a filtering afero.Fs that accepts a .gitignore file and ignores paths matched by it.

base := afero.NewMemMapFs()

gitignore, _ := os.Open("path/to/my/.gitignore")

fs, _ := ignore.NewFsFromGitIgnoreReader(base, gitignore)

filter

The filter package adds a filtering implementation of afero.Fs similar to afero.RegExpFs, but for predicates.

base := afero.NewMemMapFs()

fs := filter.NewFs(base, func(path string) bool {
	return filepath.Ext(path) == ".go"
})

docker

The docker package adds a docker afero.Fs implementation for operating on the filesystem of a container.

client := client.NewClientWithOpts(client.FromEnv)

fs := docker.NewFs(client, "my-container-id")

This package lives in a separate module to avoid adding a dependency on docker to aferox.

Go Doc

go get github.com/unmango/aferox/docker

testing

The testing package adds helper stubs for mocking filesystems in tests.

fs := &testing.Fs{
	CreateFunc: func(name string) (afero.File, error) {
		return nil, errors.New("simulated error")
	}
}

writer

The writer package adds a readonly afero.Fs implementation that dumps all file writes to the provided io.Writer. Currently paths are ignored and there are no delimeters separating files.

buf := &bytes.Buffer{}
fs := writer.NewFs(buf)

_ = afero.WriteFile(fs, "test.txt", []byte("testing"), os.ModePerm)
_ = afero.WriteFile(fs, "other.txt", []byte("blah"), os.ModePerm)

// "testingblah"
buf.String()

context

The context package adds the context.Fs interface for filesystem implementations that accept a context.Context per operation. It has a basic test suite and generally works but should be considered a 🚧 work in progress 🚧.

The context package re-exports various functions and types from the standard context packge for convenience. Currently the creation functions focus on adapting external context.Fs implementations to an afero.Fs to be used with the other utility functions.

var base context.Fs = mypkg.NewEffectfulFs()

fs := context.BackgroundFs(base)

var accessor context.AccessorFunc = func() context.Context {
	return context.Background()
}

// Equivalent to `context.BackgroundFs`
fs := context.NewFs(base, accessor)

The context.AferoFs interface is a union of afero.Fs and context.Fs, i.e. exposing both fs.Create and fs.CreateContext. I'm not sure if this actually has any value but it exists.

The context.Discard function adapts an afero.Fs to a context.AferoFs by ignoring the context.Context argument.

base := afero.NewMemMapFs()

var fs context.AferoFs = context.Discard(base)

protofs

The protofs module contains a silly little idea I had for communicating filesystem information over gRPC. The protobuf definitions are over at https://github.com/unmango/protofs/. It... works? It is not well tested and probably performs poorly. Use at your own risk.

Go Doc

Server

// Serve any afero.Fs implementation
var fs afero.Fs

server := grpc.NewServer()
protofsv1alpha1.RegisterFsServer(server, fs)
protofsv1alpha1.RegisterFileServer(server, fs)

lis, _ := net.Listen("unix", "/tmp/fs.sock")
server.Serve(lis)

Client

conn, _ := grpc.NewClient("unix:///tmp/fs.sock",
  grpc.WithTransportCredentials(insecure.NewCredentials()),
)

var fs afero.Fs = protofsv1alpha1.NewFs(conn)