Extract strings from projects using ngx-translate

Usage no npm install needed!

<script type="module">
  import sebastianzillessenNgxTranslateExtract from 'https://cdn.skypack.dev/@sebastianzillessen/ngx-translate-extract';


Build Status

NPM version

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Extract translatable (ngx-translate) strings and save as a JSON or Gettext pot file. Merges with existing strings if the output file already exists.


Install the package in your project:

npm install @sebastianzillessen/ngx-translate-extract --save-dev

Add an extract script to your project's package.json:

"scripts": {
  "extract": "ngx-translate-extract --input ./src --output ./src/assets/i18n/ --sort --format namespaced-json"

You can now run npm run extract to extract strings.

Extract examples

Extract from dir and save to file

ngx-translate-extract -i ./src -o ./src/i18n/strings.json

Extract from multiple dirs

ngx-translate-extract -i ./src/folder-a ./src/folder-b -o ./src/i18n/strings.json

Extract and save to multiple files

ngx-translate-extract -i ./src -o ./src/i18n/{da,en,fr}.json


ngx-translate-extract -i ./src -o ./src/i18n/da.json ./src/i18n/en.json ./src/i18n/fr.json

or (update only)

ngx-translate-extract -i ./src -o ./src/i18n/*.json

or (update only)

Custom indentation

By default, tabs are used for indentation when writing extracted strings to json formats:

ngx-translate-extract -i ./src -o ./src/i18n/en.json --format-indentation \t'

If you want to use spaces instead, you can do the following:

ngx-translate-extract -i ./src -o ./src/i18n/en.json --format-indentation ' '

Mark strings for extraction using a marker function

If, for some reason, you want to extract strings not passed directly to TranslateService, you can wrap them in a custom marker function.

import { _ } from '@sebastianzillessen/ngx-translate-extract';

_('Extract me');

Add the marker argument when running the extract script:

ngx-translate-extract ... -m _

Modify the scripts arguments as required.

Commandline arguments

ngx-translate-extract [options]

  --version, -v               Show version number                      [boolean]
  --help, -h                  Show help                                [boolean]
  --input, -i                 Paths you would like to extract strings from. You
                              can use path expansion, glob patterns and multiple
              [array] [default: "/home/vagrant/workspace/ngx-translate-extract"]
  --patterns, -p              Extract strings from the following file patterns
                                    [array] [default: ["/**/*.html","/**/*.ts"]]
  --output, -o                Paths where you would like to save extracted
                              strings. You can use path expansion, glob patterns
                              and multiple paths              [array] [required]
  --marker, -m                Extract strings passed to a marker function
                                                       [string] [default: false]
  --format, -f                Output format
          [string] [choices: "json", "namespaced-json", "pot"] [default: "json"]
  --format-indentation, --fi  Output format indentation [string] [default: "\t"]
  --replace, -r               Replace the contents of output file if it exists
                              (Merges by default)     [boolean] [default: false]
  --sort, -s                  Sort strings in alphabetical order when saving
                                                      [boolean] [default: false]
  --clean, -c                 Remove obsolete strings when merging
                                                      [boolean] [default: false]
  --keys, -k                  Extract only the keys without their values
                              (otherwise it prefills it with the existing text)
                                                      [boolean] [default: false]
  --prefill, --pp             Fills extracted translation keys with this pattern
                              instead of empty string     [string] [default: ""]
  --verbose, --vb             Log all output to console[boolean] [default: true]