goloc

A flexible tool for application localization using Google Sheets.

Table of Contents

• Features
• Supported OS / architectures
• Supported platforms / formats
• Setup
• Localization document
  • Localizations sheet
  • Formats sheet
• Usage
  • Android
  • Flutter
• macOS Catalina usage notes
• License

Features

• Easy configuration
• High configurability
• Precise error reporting
• Multiple supported target platforms
• Customizable format strings
• Missing localization reports

Supported OS / architectures

goloc can be built for each OS/architecture supported by golang, but release archives contain binaries only for amd64 architecture for macOS, Linux and Windows.

Supported formats

• Android
• iOS
• Flutter
• JSON

Setup

• Download a goloc.zip file from the latest release and unpack it into your project's root folder
• Download client_secret.json file from Google API Console and put it inside a newly created goloc folder. To do so, follow these steps:
  • Open Google API Console
  • Select a project (or create a new one)
  • Press ENABLE APIS AND SERVICES button
  • Find Google Sheets API
  • Press ENABLE
  • Go to Dashboard->Credentials
  • Press Create credentials->Service account key
  • Select any type of service account and JSON for key type, then press Create
  • Rename the downloaded file to client_secret.json and put it into a goloc folder of a project
• Create a new localization document
• Share your localization document with a service account created previously. To do so, follow these steps:
  • Open the client_secret.json file
  • Copy the client_email value
  • Open the localization document
  • Press SHARE button
  • Paste the client_email value into the People input field.

Localization document

Each localization document consists of formats and localizations sheets. One localization document can have multiple sheets for both.

The simplest way to create a new goloc-compatible localization document is to copy the sample spreadsheet. However, you can easily create a goloc-compatible localization document yourself just by following the simple requirements described below.

Localizations sheet

On the example above you can see a goloc-compatible localizations sheet. The rules to make a localizations sheet goloc-compatible are:

• First row must contain column names
• There must be exactly one key column and at least one language column
• Key column can have any name, but the dafault name is key
• Each language column must be named as lang_<lanaguage code>
• To define a format string, you can use {format_name} in place of the formatted value (each format must be specified in the formats sheet)

Formats sheet

On the example above you can see a goloc-compatible formats sheet. The rules to make a formats sheet goloc-compatible are:

• First row must contain column names
• There must be exactly one format column and at least one platform column
• Format column can have any name, but the dafault name is format
• Each platform column must have a name of a goloc-supported platform.
• Empty format name can be used to define a default format (used as {})

Usage

• Create a script or build task definition with parameters best suited for your project. To see available parameters, run goloc --help. goloc is distributed in form of separate executables for each platform, so don't forget to take that into account creating localization script.
• Execute the script/task whenever you want to update localized strings. goloc will automatically replace any existing localization files with the updated ones.

Android

No special configuration in code is required.

Example gradle task specification:

task "fetchLocalizations"(type: Exec) {
    def osName = System.getProperty('os.name').toLowerCase()
    def isWindows = osName.contains("win")
    def isMac = osName.contains("mac")
    def isUnix = osName.contains("nix") || osName.contains("nux") || osName.contains("aix")

    def params = [
            '--credentials', "goloc/client_secret.json",
            '--platform', 'android',
            '--spreadsheet', '1MbtglvGyEey3gH8yh4c9QovCIbtl5EcwqWqTZUiNga8',
            '--tab', "localizations",
            "--key-column", "key",
            '--resources', "app/src/main/res/",
            '--default-localization', 'en',
            '--default-localization-file-path', "app/src/main/res/values/localized_strings.xml"
    ]

    if (isWindows) {
        params = ['cmd', '/c', 'goloc\\windows_amd64.exe'] + params
    } else if (isMac) {
        params = ['./goloc/darwin_amd64'] + params
    } else if (isUnix) {
        params = ['./goloc/linux_amd64'] + params
    } else {
        logger.error('Your OS is not supported.')
        return
    }

    commandLine params
}

Flutter

Localized strings can be accessed through AppLocalizations.of(context)

Requirements:

• Add sprintf: ^4.0.2 to the dependencies section of pubspec.yaml
• Add AppLocalizationsDelegate() to localizationsDelegates of the app widget constructor
• Specify supported localizations in supportedLocales of the app widget constructor
• (Recommended) Add DefaultIntlLocaleDelegate() to localizationsDelegates of the app widget constructor. This will make intl-dependent formatters use currently selected locale.

class DefaultIntlLocaleDelegate extends LocalizationsDelegate<Null> {
  @override
  bool isSupported(Locale locale) => true;

  @override
  Future<Null> load(Locale locale) {
    Intl.defaultLocale = locale.toLanguageTag();
    return Future.value(null);
  }

  @override
  bool shouldReload(LocalizationsDelegate<AppLocalizations> old) => false;
}

Example bash localization script:

#!/bin/bash

case "$OSTYPE" in
  darwin*)  EXECUTABLE="darwin_amd64" ;;
  linux*)   EXECUTABLE="linux_amd64" ;;
  msys*)    EXECUTABLE="windows_amd64.exe" ;;
  *)
	  echo "Platform is not supported: $OSTYPE"
	  exit 1
  ;;
esac

goloc/${EXECUTABLE} -c goloc/client_secret.json -p flutter -s 1MbtglvGyEey3gH8yh4c9QovCIbtl5EcwqWqTZUiNga8 -t localizations -r lib/intl

macOS Catalina usage notes

Due to the security improvements in the macOS Catalina, any 3rd party application downloaded from the internet has to be notarized to be launched without additional actions from the user side. Since goloc is entirely free, I can't afford Apple Developer Program subscription for notarizing macOS builds. Luckily, Apple has left a way to launch a non-notarized app, but it requires some actions.

Here's the instruction on how to launch goloc on macOS Catalina:

1. Upon the first launch you'll see a window like this:
2. Go to settings and choose Security & Privacy:
3. Choose Open Anyway:
4. Re-launch goloc, and you'll see a next window:
5. Choose Open. Next time you launch goloc, macOS won't complain anymore.

License

Released under the MIT License.