gotext-tools

A Go library and CLI toolkit for working with Gettext .po and .mo files. This project provides cross-platform tools for extracting, merging, and compiling translation files, with a focus on Go projects.

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Features

✅ Cross-platform – Written in Go, works on Linux, NetBSD, FreeBSD, OpenBSD, Windows, Darwin(MacOS), Plan9, Solaris and DragonFly. 386, amd64, arm, arm64, ppc64, ppc64le, riscv64.

✅ Go-native support – Designed with Go projects in mind.
✅ Easy to Install – Pre-built binaries available, or build from source.

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CLI Tools

Located in cli/, these tools provide command-line utilities for managing .po and .mo files.

gotext-tools

It is a wrapper of all the utilities that will be mentioned below, if you don't want to install all of them one by one, or you want to save disk space, I recommend you install this one.

Usage:

gotext-tools [tool] [option]... [arg]...

msgomerge

A cross-platform alternative to msgmerge, used for updating .po files with new translations while preserving existing ones.

Usage:

msgomerge [old.po] [new.po] -o [output.po]

More information here

msgofmt

A cross-platform alternative to msgfmt, used for compiling .po files into binary .mo files.

Usage:

msgofmt [input.po] -o [output.mo]

More information here

xgotext

A Go-compatible version of xgettext for extracting translatable strings from Go source code.

Usage:

xgotext -o [output.po] [file1.go] [file2.go] ...

More information here

msgocat

A cross-platform alternative to msgcat, used to concatenate and merge .po files.

Usage:

msgocat [file1.po] [file2.po]

More information here

msgounfmt

A cross-platform alternative to msgunfmt, used to convert .mo files to .po format.

Usage:

msgounfmt myFile.mo -o myFile.po

More information here

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📌 Coming Soon: More CLI tools for advanced Gettext operations.

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Library

The core library is located in pkg/ and provides structured handling of .po and .mo files.

go/parse

Extracts Gettext-compatible strings from Go source code. Useful for generating translation templates.

Example:

Details

package main

import (
  goparse"github.com/Tom5521/gotext-tools/v2/pkg/go/parse"
  "fmt"
)

func main(){
  myGolangFile := `package main

  import "fmt" // Import strings are ignored!

  func MyFunc(){
    a := 10
    "My anonymous string"

    switch "a"{
      case "b":
      case "c":
    }
  }`

  file,err := goparse.FromString(myGolangFile,"my-file.go")
  if err != nil{
    panic(err)
  }

  fmt.Println(file.Entries)
}

po

The main package for working with .po files. Includes:

• Entry & Entries – Structured representation of translation entries.
• File
• Sorting & Comparison – Easily organize and compare translations.

Details

package main

import (
  "os"
  "github.com/Tom5521/gotext-tools/v2/pkg/po"
  "github.com/Tom5521/gotext-tools/v2/pkg/po/compiler"
  "github.com/Tom5521/gotext-tools/v2/pkg/po/parse"
)


func main(){
  def,_ := parse.Mo("es.mo")
  ref,_ := parse.Po("en.pot")
  if def.Equal(ref){
    return
  }

  merged := po.Merge(def.Entries,ref.Entries)
  merged = merged.CleanFuzzy().CleanDuplicates()
  compiler.PoToWriter(merged,os.Stdout)
}

po/compile

Compiles parsed .po files into .mo (binary) or updated .po files.

Details

package main

import (
  "os"
  "github.com/Tom5521/gotext-tools/v2/pkg/po"
  "github.com/Tom5521/gotext-tools/v2/pkg/po/compile"
)

func main(){
  myFile := &po.File{
    Name: "My File!",
    Entries: po.Entries{
      {
        ID: "Hello World!",
        Str: "Hola Mundo!",
      },
      {
        ID: "Bye World!",
        Str: "Adios Mundo!",
      },
    },
  }

  compile.PoToWriter(myFile,os.Stdout)
}

po/parse

Parsers for reading .po and .mo files into structured Go objects.

Details

package main

import (
  "github.com/Tom5521/gotext-tools/v2/pkg/po/parse"
)

func main(){
  myPoFile := `msgid "hello"
msgstr "hola"

#, fuzzy
msgid "world"
msgstr "mundo"`

  myFile,_ := parse.PoFromString(myPoFile,"my_po_file.po")
}

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Installation

From Source

git clone https://github.com/Tom5521/gotext-tools
cd gotext-tools
make local-install APP=gotext-tools

Or...

git clone https://github.com/Tom5521/gotext-tools
cd gotext-tools
make go-install-gotext-tools

Pre-built Binaries

Check the Releases page for pre-compiled executables.

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Notes

Recommendation: the version of this module is go1.18, it will work fine, but if you need better performance I recommend you to use go1.21 as minimum, since several internal functions are manual implementations (since for go1.18 they haven't added some libraries yet) so they are a bit slower than the official implementations.

Here is an example with benchmarks:

Go 1.24.3

$ make bench path=./pkg/po/compile/mo_benchmark_test.go
goos: linux
goarch: amd64
cpu: Intel(R) Core(TM) i5-3330 CPU @ 3.00GHz
BenchmarkMoCompiler/WithHashTable-4               169875              5946 ns/op
BenchmarkMoCompiler/WithoutHashTable-4            218752              5495 ns/op
PASS
ok      command-line-arguments  2.350s

Go 1.18

$ make GOCMD=go1.18 bench path=./pkg/po/compile/mo_benchmark_test.go
goos: linux
goarch: amd64
cpu: Intel(R) Core(TM) i5-3330 CPU @ 3.00GHz
BenchmarkMoCompiler/WithHashTable-4               135243              7897 ns/op
BenchmarkMoCompiler/WithoutHashTable-4            161006              7837 ns/op
PASS
ok      command-line-arguments  2.507s

I have to note that this only applies to the library, the CLI binaries use a module with version 1.23 and are compiled with the latest version of golang, so these problems do not affect them.

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Contributing

Contributions are welcome! Feel free to open issues or submit pull requests.

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License

This project is open-source under the MIT License. See LICENSE for details.