wan24-I8NTool

This is a small dotnet tool for extracting stings to translate from source code and writing the result in the PO format to a file or STDOUT. It can also be used to create i8n files, which are easy to use from any app.

It's pre-configured for use with the wan24-Core translation helpers for C#, but it can be customized easily for any environment and any programming language by customizing the used regular expressions in your own configuration file (find available presets in the config folder of this repository).

Usage

Where to get it

This is a dotnet tool and can be installed from the command line:

dotnet tool install -g wan24-I8NTool

The default installation folder is

• %USER%\.dotnet\tools for Windows
• ~/.dotnet/tools for Linux (or MAC)

NOTE: Please ensure that your global .NET tool path is in the PATH environment variable (open a new Windows terminal after adding the path using Settings -> System -> Extended system settings -> Extended -> Environment variables).

Simple usage

With pre-configuration for .NET:

wan24I8NTool --input ./ > keywords.po

You can find other pre-configurations in the config/*.json files in the GitHub repository:

wan24I8NTool --config file.json --input ./ > keywords.po

If you want to use advanced options, you can display help like this:

wan24I8NTool help (--api API (--method METHOD)) (-details)

For individual usage support, please open an issue here.

NOTE: The wan4-Core CLI configuration (CliConfig) will be applied, so advanced configuration is possible using those special command line arguments.

Default keyword extraction process

Per default keywords will be found by the regular expressions you can find in config/dotnet.json. They'll then be post-processed by the replacement expressions, until the final quoted keyword was extracted from a line.

These default translation method names can be parsed from source code:

• _
• gettext(n|d)("..."
• Translate(Plural)("..."
• GetTerm("..."

There are also some attributes, which can define translated text:

• StdIn("..."
• StdOut("..."
• StdErr("..."
• Description("..."
• DisplayText("..."

And these attribute peoperty strings will also be parsed:

• Example = "..."
• ErrorMessage = "..."

Finally, there are also attributes, which get the text to translate as a 2nd argument after a numeric argument:

• ExitCode(N, "..."

NOTE: (Multiline) concatenated string value definitions (like @"Part \ a" + $"Part b {variable}") or interpolations can't be parsed. The matched string literal must be JSON style escaped.

To force including any string (from a constant definition, for example), simply add a comment wan24I8NTool:include at the end of the line - example:

public const string NAME = "Any PO included keyword";// wan24I8NTool:include

To force excluding any line, simply add a comment wan24I8NTool:exclude to that line - example:

string text = gettext("Text file keyword");// wan24I8NTool:exclude

This will avoid including the text file ID Text file keyword (see below) as an additional term to translate into the catalog.

Custom parser configuration

In the config/dotnet.json file of this repository you find the default configuration. You can download and modify it for your needs, and use it with the --config parameter.

Example parser JSON configuration:

{
	"SingleThread": false,// (optional) Set to true to disable multithreading (may be overridden by -singleThread)
	"Encoding": "UTF-8",// (optional) Source encoding to use (default is UTF-8; may be overridden by --encoding)
	"Patterns": [// (optional)
		{
			// Matching only pattern
			"Pattern": "Regular expression",// Pattern for use with RegEx
			"Options": "None"// RegexOptions enumeration
		},
		{
			// Matching and replacement pattern
			"Pattern": "Regular expression",// Pattern for use with RegEx
			"Options": "None",// RegexOptions enumeration
			"Replacement": "$1"// Replacement expression
		},
		{
			// Replacement-only pattern
			"Pattern": "Regular expression",// Pattern for use with RegEx
			"Options": "None",// RegexOptions enumeration
			"Replacement": "$1",// Replacement expression
			"ReplaceOnly": true// Disable use for matching
		}
		...
	],
	"FileExtensions": [// (optional) File extensions to include when walking through a folder tree (may be overridden by --ext)
		".ext",
		...
	],
	"TextFileExtensions": [// (optional) Text file extensions to include when walking through a folder tree (may be overridden by --textFileExt)
		".ext.txt",
		...
	],
	"MergeOutput": true,// (optional) Merge the extracted keywords to the existing output PO file
	"FailOnError": true,// (optional) To fail thewhole process on any error
	"Merge": false// (optional) Set to true to merge your custom configuration with the default configuration
}

When loading the configuration, the pattern property Options will be extended by the SingleLine and Compiled default options.

TIPP: You may use the variable %{rxStringLiteral} to match a double quoted string literal.

The parser looks for any matching non-replacement-only expression, then applies all matching replacement expressions to refer to the keyword to use, finally.

NOTE: The final keyword must be a valid JSON string literal in single or double quotes!

During merging lists will be combined, and single options will be overwritten.

There are some more optional keys for advanced configuration:

• Core: wan24-Core configuration using a AppConfig structure
• CLI: wan24-CLI configuration using a CliAppConfig structure

About including text files

The extractor API does also incude text files - per default filtered by:

• *.translate.txt (for simple text)
• *.translate.md (for MarkDown text)

When doing so, you can address the translation using the filename without extensions as keyword - example for Info text.translate.txt:

string text = _("Info text");// wan24I8NTool:exclude

The wan24I8NTool:exclude does tell the extractor to skip adding Info text as keyword to translate, because what you want to translate, is the text file content, but not the keyword used to load the translation in that case.

Build, extract, display and use an i8n file

i8n files contain optional compressed translation terms. They can be created from PO/MO and/or JSON dictionary (keyword as key, translation as an array of strings as value) or wan24-I8NKws input files like this:

wan24I8NTool i8n -compress --poInput /path/to/input.po --output /path/to/output.i8n

An i8n file can be embedded into an app, for example.

To convert all *.json|po|mo|kws files in the current folder to *.i8n files:

wan24I8NTool i8n buildmany -compress -verbose

To display some i8n file informations:

wan24I8NTool i8n display --input /path/to/input.i8n

To extract some i8n file to a JSON file (prettified):

wan24I8NTool i8n extract --input /path/to/input.i8n --jsonOutput /path/to/output.json

To extract some i8n file to a PO file:

wan24I8NTool i8n extract --input /path/to/input.i8n --poOutput /path/to/output.po

To extract some i8n file to a wan24-I8NKws file:

wan24I8NTool i8n extract --input /path/to/input.i8n --kwsOutput /path/to/output.kws

NOTE: For more options and usage instructions please use the CLI API help (see below).

TIPP: You can use the i8n API for converting, merging and validating the supported source formats also.

In a .NET app you can use an i8n file using the wan24-I8N(-Compressed) NuGet packages and wan24-Core:

// Uncompressed using the wan24-I8N NuGet package
Translation.Current = new(await I8NTranslationTerms.FromStreamAsync(fileStream));

// Compressed using the wan24-I8N-Compressed NuGet package
Translation.Current = new(await I8NCompressedTranslationTerms.FromStreamAsync(fileStream));

The FromStream(Async) methods also allow to specify, if there's no i8n header to read.

Links to used NuGet packages:

• wan24-Core
• wan24-I8N
• wan24-I8N-Compressed

i8n file structure in detail

If you didn't skip writing a header during build, the first byte contains the version number and a flag (bit 8), if the body is compressed. The file body is a JSON encoded dictionary, having the keyword as ID, and the translations as value (an array of strings with none, one or multiple (plural) translations).

If compressed, the wan24-Compression default compression algorithm was used. This is Brotli at the time of writing. But please note that wan24-Compression writes a non-standard header before the body, which is required for compatibility of newer wan24-Compression library versions with older compressed contents.

NOTE: For using compressed i8n files, you'll have to use the wan24-Compression NuGet package in your .NET app for decompressing the body.

Please see the I8NApi(.Internals).cs source code in this GitHub repository for C# code examples.

TIPP: Use compression and the i8n header only, if you're using the i8n file from a .NET app. Without a header and compression you can simply deserialize the JSON dictionary from the i8n file using any modern programming language.

Steps to i8n

Internationalization (i8n) for apps is a common task to make string used in apps translatable. gettext is a tool which have been around for many years now and seem to satisfy developers, translators and end users.

The steps to i8n your app are:

1. use l10n methods in your code when you want to translate a term
2. extract keywords (terms) from your source code into a PO file using an extractor
3. translate the terms using an editor tool and create a MO file
4. load the MO file using your apps gettext-supporting library

wan24-I8NTool is a CLI tool which you can use as extractor to automatize things a bit more, and you're also free to use other translation file formats.

If you'd like to use the i8n file format from wan24-I8NTool in your .NET app, the last step is replaced by:

• convert the PO/MO file to an i8n file using wan24-I8NTool
• load the i8n file using your .NET app using the wan24-I8N library

This is one additional step, but maybe worth it, if you don't want to miss features like compressed i8n files ready-to-use i8n wan24-Core localization (l10n) features. You'll also not need to reference any gettext supporting library or do the parsing of the PO/MO format by yourself. You also may not need to reference the wan24-I8N(-Compressed) NuGet package, if you can manage to load the i8n structure by yourself (which is an easy task) - find examples in the wan24-I8N(-Compressed) projects in this repository.

Links to useful NuGet packages:

• wan24-Core
• wan24-I8N
• wan24-I8N-Compressed