ensure/README.md

ensure

Ensure is a small library to help ensure state on a UNIX system. It is currently pretty basic and doesn't have much to offer apart from a file/directory and exec helper.

But with these small pieces more should easily be possible and go offers more than enough to implement other functions on top of the ensurer interface and the runner to ensure the state.

how to use

To use this library use one of the provided resources or implement one yourself with the Ensurer interface.

Either call Ensure on the resource yourself or let one of the runners do it for all your resources.

package main

import (
  "io/ioutil"
  "os"
  "path"

  "git.zero-knowledge.org/gibheer/ensure"
  "git.zero-knowledge.org/gibheer/ensure/file"
)

func main() {
  tmpDir, _ := ioutil.TempDir("", "")
  defer os.RemoveAll(tmpDir)
  f := &file.F{
    Path: path.Join(tmpDir, "test")
  }
  if !f.Is() {
    if err := f.Ensure(); err != nil {
      fmt.Fatalf("could not ensure file: %s\n", err)
    }
  }

  // Use a runner to ensure multiple resources blocked by a check.
  // In case of the runner, ensure will also run Is() before making changes.
  // Better read the documentation, not all resources do that or can do that.
  r := &ensure.Runner{
    States: []ensure.Ensurer{f},
    Is: f.Is,
  }
  if err := r.Ensure(); err != nil {
    fmt.Fatalf("could not ensure directory: %s", err)
  }
}