diff options
Diffstat (limited to 'searx/utils.py')
-rw-r--r-- | searx/utils.py | 53 |
1 files changed, 49 insertions, 4 deletions
diff --git a/searx/utils.py b/searx/utils.py index cda336035..c3958ae78 100644 --- a/searx/utils.py +++ b/searx/utils.py @@ -53,6 +53,9 @@ _LANG_TO_LC_CACHE: Dict[str, Dict[str, str]] = {} _FASTTEXT_MODEL: Optional["fasttext.FastText._FastText"] = None """fasttext model to predict laguage of a search term""" +SEARCH_LANGUAGE_CODES = frozenset([searxng_locale[0].split('-')[0] for searxng_locale in language_codes]) +"""Languages supported by most searxng engines (:py:obj:`searx.languages.language_codes`).""" + class _NotSetClass: # pylint: disable=too-few-public-methods """Internal class for this module, do not create instance of this class. @@ -637,11 +640,53 @@ def _get_fasttext_model() -> "fasttext.FastText._FastText": return _FASTTEXT_MODEL -def detect_language(text: str, threshold: float = 0.3, min_probability: float = 0.5) -> Optional[str]: - """https://fasttext.cc/docs/en/language-identification.html""" +def detect_language(text: str, threshold: float = 0.3, only_search_languages: bool = False) -> Optional[str]: + """Detect the language of the text parameter + + Args: + * text (str): the string whose language is to be detected. + * threshold (float): threshold filters the returned labels by a threshold on probability. + A choice of 0.3 will return labels with at least 0.3 probability. + * only_search_languages (bool): if True, returns only supported SearXNG search languages. + see :py:obj:`searx.languages` + + + Raises: + * ValueError: if text is not a string + + Returns: + * result (str, None): the detected language code or None. See below. + + The language detection is done by using `a fork`_ of the fastText_ library (`python + fasttext`_). fastText_ distributes the `language identification model`_, for + reference: + + - `FastText.zip: Compressing text classification models`_ + - `Bag of Tricks for Efficient Text Classification`_ + + The `language identification model`_ support the language codes (ISO-639-3):: + af als am an ar arz as ast av az azb ba bar bcl be bg bh bn bo bpy br bs bxr + ca cbk ce ceb ckb co cs cv cy da de diq dsb dty dv el eml en eo es et eu fa + fi fr frr fy ga gd gl gn gom gu gv he hi hif hr hsb ht hu hy ia id ie ilo io + is it ja jbo jv ka kk km kn ko krc ku kv kw ky la lb lez li lmo lo lrc lt lv + mai mg mhr min mk ml mn mr mrj ms mt mwl my myv mzn nah nap nds ne new nl nn + no oc or os pa pam pfl pl pms pnb ps pt qu rm ro ru rue sa sah sc scn sco sd + sh si sk sl so sq sr su sv sw ta te tg th tk tl tr tt tyv ug uk ur uz vec vep + vi vls vo wa war wuu xal xmf yi yo yue zh + + .. _a fork: https://github.com/searxng/fasttext-predict + .. _fastText: https://fasttext.cc/ + .. _python fasttext: https://pypi.org/project/fasttext/ + .. _language identification model: https://fasttext.cc/docs/en/language-identification.html + .. _Bag of Tricks for Efficient Text Classification: https://arxiv.org/abs/1607.01759 + .. _`FastText.zip: Compressing text classification models`: https://arxiv.org/abs/1612.03651 + """ if not isinstance(text, str): raise ValueError('text must a str') r = _get_fasttext_model().predict(text.replace('\n', ' '), k=1, threshold=threshold) - if isinstance(r, tuple) and len(r) == 2 and len(r[0]) > 0 and len(r[1]) > 0 and r[1][0] > min_probability: - return r[0][0].split('__label__')[1] + if isinstance(r, tuple) and len(r) == 2 and len(r[0]) > 0 and len(r[1]) > 0: + language = r[0][0].split('__label__')[1] + if only_search_languages and language not in SEARCH_LANGUAGE_CODES: + return None + return language return None |