Golang : Find files by name - cross platform example

Problem:

You want to find or locate files by name or by wildcard in your Golang program to do stuff like renaming files or archiving log files. You also want the solution to be cross platform and want the search facility to be available without "shelling out" or "os.Exec" to use specific operating system find program. How to do that?

Solution:

Use filepath.Glob() function to search for files by name in a given target directory and handle wildcard * search.

Here you go!

---

 package main

 import (
 "fmt"
 "os"
 "path/filepath"
 )

 func findFile(targetDir string, pattern []string) {

 for _, v := range pattern {
 matches, err := filepath.Glob(targetDir + v)

 if err != nil {
 fmt.Println(err)
 }

 if len(matches) != 0 {
 fmt.Println("Found : ", matches)
 }
 }
 }

 func main() {

 if len(os.Args) <= 2 {
 fmt.Printf("USAGE : %s <target_directory> <target_filename or part of filename> \n", os.Args[0])
 os.Exit(0)
 }

 targetDirectory := os.Args[1] // get the target directory
 fileName := os.Args[2:] // to handle wildcard such as filename*.go

 findFile(targetDirectory, fileName)

 }

Sample output:

./findfilebyname2 ../ find*

will return nothing, because no file the starts with find is found on upper directory.

./findfilebyname2 ./ find*

Found : [./findallindex.go]

Found : [./findbiggest.go]

Found : [./findduplicate]

Found : [./findduplicate.go]

Found : [./findfilebyname.go]

Found : [./findfilebyname2]

Found : [./findfilebyname2.go]

Found : [./findsmallest.go]

just searching for a single file in target directory

./findfilebyname2 /Users/admin/ findsmallest.go

Found : [/Users/admin/findsmallest.go]

NOTE: If you are looking to search from a given target directory and traverse down the directory hierarchy, you will need to use filepath.Walk() to do that. See example at https://www.socketloop.com/tutorials/golang-find-file-size-disk-usage-with-filepath-walk

References:

https://www.socketloop.com/tutorials/golang-how-to-check-if-slice-or-array-is-empty

https://www.socketloop.com/tutorials/golang-use-wildcard-patterns-with-filepath-glob-example

https://www.socketloop.com/tutorials/golang-find-duplicate-files-with-filepath-walk