translation-keys-generator

Generate typescript interface for a given json translation table

This generator is used in conjunction with value-to-keys to achieve auto completion and type-checking when dealing with translations.

Example say you have a json translation table as below (en.json)

{
  "Common": {
    "NoMatch": "No match"
  }
}

you can get the translation like so

translate.get(Keys.Common.NoMatch); // Keys.Common.NoMatch will result in "Common.NoMatch"

or inside the view

<span> {{ Keys.Common.NoMatch | translate }} </span>

Note that the example above assume you are using a translation library that supports namespaces in keys (e.g. ngx-translate)

How to use

Step 1: Prepare the translation interface

npm install --save-dev translation-keys-generator

then add a script that executes the following

import { generator } from "translation-keys-generator";
generator.generateAsFile({ json: "en.json", path: "translation.interface.d.ts" });

that will provide us with an interface that matches our translation table, the interface will help us get auto-completion.

Note the generator belongs to the build process, you shouldn't include it in your app.

Step 2: Prepare the translation keys

We'll basically take the en.json, loop through all the values and replace them with keys.

In our example above, if we were to:

import { default as translationTable } from "en.json";
console.log(translationTable.Common.NoMatch); // outputs "No match"

It will output "No match", so what need to do is replace "No match" with "NoMatch".

For that install the following

npm install --save values-to-keys

Then add a .ts file that contains the following (this file should be bundled with your app)

import { replace } from "values-to-keys";
import { default as translationTable } from "en.json";
import { ITranslationKeys } from "translation.interface"; // the interface we generated in step 1

replace(translationTable);
export const TranslationKeys = translationTable as ITranslationKeys;

Step 3: Use the translation keys

Now import the TranslationKeys constant in other classes and enjoy the auto completion.

import { TranslationKeys as Keys } from "keys.ts";
translateService.get(Keys.Common.Great);

License MIT.