WIP: Reimplementing search_dates

dateparser/search/__init__.py

@@ -1,63 +1,119 @@
-from dateparser.search.search import DateSearchWithDetection
+from dateparser.search.search import DateSearch
+from dateparser.conf import apply_settings
 
 
-_search_with_detection = DateSearchWithDetection()
+_search_dates = DateSearch()
 
 
+@apply_settings
 def search_dates(text, languages=None, settings=None, add_detected_language=False, detect_languages_function=None):
     """Find all substrings of the given string which represent date and/or time and parse them.
 
-        :param text:
-            A string in a natural language which may contain date and/or time expressions.
-        :type text: str
-
-        :param languages:
-            A list of two letters language codes.e.g. ['en', 'es']. If languages are given, it will
-            not attempt to detect the language.
-        :type languages: list
-
-        :param settings:
-            Configure customized behavior using settings defined in :mod:`dateparser.conf.Settings`.
-        :type settings: dict
-
-        :param add_detected_language:
-            Indicates if we want the detected language returned in the tuple.
-        :type add_detected_language: bool
-
-        :param detect_languages_function:
-            A function for language detection that takes as input a `text` and a `confidence_threshold`,
-            and returns a list of detected language codes.
-            Note: detect_languages_function is only uses if `languages` are not provided.
-        :type detect_languages_function: function
-
-        :return: Returns list of tuples containing:
-            substrings representing date and/or time, corresponding :mod:`datetime.datetime`
-            object and detected language if *add_detected_language* is True.
-            Returns None if no dates that can be parsed are found.
-        :rtype: list
-        :raises: ValueError - Unknown Language
-
-        >>> from dateparser.search import search_dates
-        >>> search_dates('The first artificial Earth satellite was launched on 4 October 1957.')
-        [('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0))]
-
-        >>> search_dates('The first artificial Earth satellite was launched on 4 October 1957.',
-        >>>              add_detected_language=True)
-        [('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0), 'en')]
-
-        >>> search_dates("The client arrived to the office for the first time in March 3rd, 2004 "
-        >>>              "and got serviced, after a couple of months, on May 6th 2004, the customer "
-        >>>              "returned indicating a defect on the part")
-        [('in March 3rd, 2004 and', datetime.datetime(2004, 3, 3, 0, 0)),
-         ('on May 6th 2004', datetime.datetime(2004, 5, 6, 0, 0))]
-
-        """
-    result = _search_with_detection.search_dates(
+    :param text:
+        A string in a natural language which may contain the date and/or time expressions.
+    :type text: str
+
+    :param languages:
+        A list of two letters language codes.e.g. ['en', 'es']. If languages are given, it will
+        not attempt to detect the language.
+    :type languages: list
+
+    :param settings:
+           Configure customized behavior using settings defined in :mod:`dateparser.conf.Settings`.
+    :type settings: dict
+
+    :param add_detected_language:
+           Indicates if we want the detected language returned in the tuple.
+    :type add_detected_language: bool
+
+    :return: Returns list of tuples containing:
+             substrings representing date and/or time, corresponding :mod:`datetime.datetime`
+             object and detected language if *add_detected_language* is True.
+             Returns None if no dates that can be parsed are found.
+    :rtype: list
+    :raises: ValueError - Unknown Language
+
+    >>> from dateparser.search import search_dates
+    >>> search_dates('The first artificial Earth satellite was launched on 4 October 1957.')
+    [('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0))]
+
+    >>> search_dates('The first artificial Earth satellite was launched on 4 October 1957.',
+    >>>              add_detected_language=True)
+    [('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0), 'en')]
+
+    >>> search_dates("The client arrived to the office for the first time in March 3rd, 2004 "
+    >>>              "and got serviced, after a couple of months, on May 6th 2004, the customer "
+    >>>              "returned indicating a defect on the part")
+    [('in March 3rd, 2004 and', datetime.datetime(2004, 3, 3, 0, 0)),
+     ('on May 6th 2004', datetime.datetime(2004, 5, 6, 0, 0))]
+
+    """
+
+    result = _search_dates.search_dates(
         text=text, languages=languages, settings=settings, detect_languages_function=detect_languages_function
     )
-    dates = result.get('Dates')
+
+    dates = result.get("Dates")
     if dates:
         if add_detected_language:
-            language = result.get('Language')
-            dates = [date + (language, ) for date in dates]
+            language = result.get("Language")
+            dates = [date + (language,) for date in dates]
         return dates
+
+
+@apply_settings
+def search_first_date(text, languages=None, settings=None, add_detected_language=False, detect_languages_function=None):
+    """Find first substring of the given string which represent date and/or time and parse it.
+
+    :param text:
+        A string in a natural language which may contain the date and/or time expression.
+    :type text: str
+
+    :param languages:
+        A list of two letters language codes.e.g. ['en', 'es']. If languages are given, it will
+        not attempt to detect the language.
+    :type languages: list
+
+    :param settings:
+           Configure customized behavior using settings defined in :mod:`dateparser.conf.Settings`.
+    :type settings: dict
+
+    :param add_detected_language:
+           Indicates if we want the detected language returned in the tuple.
+    :type add_detected_language: bool
+
+    :return: Returns a tuple containing:
+             substring representing date and/or time, corresponding :mod:`datetime.datetime`
+             object and detected language if *add_detected_language* is True.
+             Returns None if no dates that can be parsed are found.
+    :rtype: tuple
+    :raises: ValueError - Unknown Language
+
+    >>> from dateparser.search import search_first_date
+    >>> search_first_date('The first artificial Earth satellite was launched on 4 October 1957.')
+    ('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0))
+
+    >>> from dateparser.search import search_first_date
+    >>> search_first_date('Caesar Augustus, also known as Octavian')
+    None
+
+    >>> search_first_date('The first artificial Earth satellite was launched on 4 October 1957.',
+    >>>              add_detected_language=True)
+    ('on 4 October 1957', datetime.datetime(1957, 10, 4, 0, 0), 'en')
+
+    >>> search_first_date("The client arrived to the office for the first time in March 3rd, 2004 "
+    >>>              "and got serviced, after a couple of months, on May 6th 2004, the customer "
+    >>>              "returned indicating a defect on the part")
+    ('in March 3rd, 2004 and', datetime.datetime(2004, 3, 3, 0, 0))
+
+    """
+
+    result = _search_dates.search_dates(
+        text=text, languages=languages, limit_date_search_results=1, settings=settings, detect_languages_function=detect_languages_function
+    )
+    dates = result.get("Dates")
+    if dates:
+        if add_detected_language:
+            language = result.get("Language")
+            dates = [date + (language,) for date in dates]
+        return dates[0]

dateparser/search/languages.py

@@ -0,0 +1,48 @@
+from collections.abc import Set
+
+from dateparser.search.text_detection import FullTextLanguageDetector
+from dateparser.languages.loader import LocaleDataLoader
+from dateparser.custom_language_detection.language_mapping import map_languages
+
+
+class SearchLanguages:
+    def __init__(self):
+        self.loader = LocaleDataLoader()
+        self.available_language_map = self.loader.get_locale_map()
+        self.language = None
+
+    def get_current_language(self, language_shortname):
+        if self.language is None or self.language.shortname != language_shortname:
+            self.language = self.loader.get_locale(language_shortname)
+
+    def translate_objects(self, language_shortname, text, settings):
+        self.get_current_language(language_shortname)
+        result = self.language.translate_search(text, settings=settings)
+        return result
+
+    def detect_language(self, text, languages, settings=None, detect_languages_function=None):
+        if detect_languages_function and not languages:
+            detected_languages = detect_languages_function(
+                text, confidence_threshold=settings.LANGUAGE_DETECTION_CONFIDENCE_THRESHOLD
+            )
+            detected_languages = map_languages(detected_languages) or settings.DEFAULT_LANGUAGES
+            return detected_languages[0] if detected_languages else None
+
+        if isinstance(languages, (list, tuple, Set)):
+            if all([language in self.available_language_map for language in languages]):
+                languages = [self.available_language_map[language] for language in languages]
+            else:
+                unsupported_languages = set(languages) - set(self.available_language_map.keys())
+                raise ValueError("Unknown language(s): %s" % ', '.join(map(repr, unsupported_languages)))
+        elif languages is not None:
+            raise TypeError("languages argument must be a list (%r given)" % type(languages))
+
+        if languages:
+            self.language_detector = FullTextLanguageDetector(languages=languages)
+        else:
+            self.language_detector = FullTextLanguageDetector(list(self.available_language_map.values()))
+
+        detected_language = self.language_detector._best_language(text) or (
+            settings.DEFAULT_LANGUAGES[0] if settings.DEFAULT_LANGUAGES else None
+        )
+        return detected_language