在Go的父目录中以递归方式查找具有名称的文件

Question

I have a directory:

basepath + /my/sub/directory

In that subdirectory, I have multiple instances of a file with name file.json

Example:

my/file.json
my/sub/file.json
my/sub/directory/file.json

What I want to do is use the full directory path and walk BACK up the file tree until I hit the basepath and find all the filepaths for the file.json

I looked at filepath.Walk but that seems to go downwards through the directory tree, not upwards

Answer 1

Here's one way you can walk backwards and read each file.json along the way.

Example project directory structure:

./
  - main.go
  ./my
    - file.json > {"location": "/my"}
    ./my/sub
      - file.json > {"location": "/my/sub"}
      ./my/sub/dir
        - file.json > {"location": "/my/sub/dir"}

---

main.go

package main

import (
    "fmt"
    "io/ioutil"
    "path/filepath"
)

func main() {
    basePath := "./"
    targetPath := basePath + "my/sub/dir"
    fileName := "file.json"

    for {
        rel, _ := filepath.Rel(basePath, targetPath)

        // Exit the loop once we reach the basePath.
        if rel == "." {
            break
        }

        // Simple file reading logic.
        dat, err := ioutil.ReadFile(fmt.Sprintf("%v/%v", targetPath, fileName))
        if err != nil {
            panic(err)
        }
        fmt.Println(string(dat))

        // Going up!
        targetPath += "/.."
    }

}

---

Output:

{ "location": "/my/sub/dir" }
{ "location": "/my/sub" }
{ "location": "/my" }

Hope you find this approach useful.