Create helper.py

helper.py

@@ -0,0 +1,156 @@
+import spacy 
+import re
+
+from datetime import datetime
+
+
+# load the spacy model
+spacy.cli.download("en_core_web_lg")
+nlp = spacy.load("en_core_web_lg")
+
+
+# Define a function to extract dates from text
+def extract_dates(text):
+    """
+    Identify dates both in numeric and free-text from text, using date regex patterns and NER tag
+    """
+
+    # Define regex patterns for common date formats
+    # Regular expressions that include the \b word boundary character to ensure that the date pattern only matches if it is not part of a longer pattern that has already been matched
+    date_patterns = [
+        r'\b\d{1,2}[-/]\d{1,2}[-/]\d{2,4}\b',  # Matches dates like "01/01/22" or "1-1-2022"
+        r'\b\d{1,2}[-/]\d{1,2}\b(?!\d)',       # Matches dates like "01/01" or "1-1"
+        r'\b[A-Z][a-z]{2,8} \d{1,2},? \d{2,4}\b',  # Matches dates like "January 1, 2022" or "Feb 28, 22"
+        r'\b\d{1,2} [A-Z][a-z]{2,8} \d{2,4}\b',  # Matches dates like "1 January 2022" or "28 Feb 22"
+        r'\b[A-Z][a-z]{2,8} \d{2,4}\b',        # Matches dates like "January 2022" or "Feb 22"
+        
+    ]
+
+    # Find all matches for date patterns in the text
+    matches = []
+    for pattern in date_patterns:
+        for match in re.findall(pattern, text):
+
+            # Check if the match is part of a longer date pattern that has already been matched
+            if all(match not in m for m in matches):
+                matches.append(match)
+    
+    # Use SpaCy to extract additional dates
+    doc = nlp(text)
+
+    for ent in doc.ents:
+        if ent.label_ == 'DATE':
+            date_str = ent.text
+
+            # Checks each SpaCy date reference against the matches list to ensure that it is not already included
+            if all(date_str not in m for m in matches):
+                matches.append(date_str)
+    
+    # Remove duplicates and return the matches
+    return list(set(matches))
+
+
+def convert_dates(date_list):
+  """
+  Assign to the identified formatted dates the proper date format and then, on the formatted dates, assign the relevant date tags (e.g. specify which is the day, the month, etc)
+  """
+
+  DATE_FORMATS = {
+      '%B %d, %Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%-m-%d-%Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m-%d-%y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d/%m': 'day:{dt.day}, month:{dt.month}',
+      '%B %d': 'day:{dt.day}, month:{dt.month}',
+      '%b %d': 'day:{dt.day}, month:{dt.month}',
+      '%B %Y': 'month:{dt.month}, year:{dt.year}',
+      '%Y': 'year:{dt.year}',
+      '%d/%m/%y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%B %d, %y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%b %d, %y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d-%m-%Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d/%m/%Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d-%m-%y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m/%d/%y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m/%d/%Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m-%d-%Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m-%d-%y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d/%m/%Y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%d/%m/%y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%m/%d/%Y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%m/%d/%y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%Y-%m-%d': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%y-%m-%d': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%m-%d-%Y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%m-%d-%y %H:%M:%S': 'day:{dt.day}, month:{dt.month}, year:{dt.year}, time:{dt.strftime("%H:%M:%S")}',
+      '%m-%d': 'month:{dt.month}, day:{dt.day}',
+      '%-m-%-d': 'month:{dt.month}, day:{dt.day}',
+      '%d %b %y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d %B %Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%b %Y': 'month:{dt.month}, year:{dt.year}',
+      '%b %d, %Y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}',
+      '%d %B %y': 'day:{dt.day}, month:{dt.month}, year:{dt.year}'  
+  }
+
+
+  output_list = []
+  for date_str in date_list:
+      valid_format = False
+      for fmt, out_fmt in DATE_FORMATS.items():
+          try:
+              dt = datetime.strptime(date_str, fmt)
+              output_list.append(out_fmt.format(dt=dt))
+              valid_format = True
+              break
+          except ValueError:
+              pass
+      if not valid_format:
+          # Attempt to parse using a custom format
+          try:
+              if '-' in date_str:
+                  dt = datetime.strptime(date_str, '%m-%d-%y')
+              else:
+                  dt = datetime.strptime(date_str, '%d/%m/%y')
+              output_list.append(f'day:{dt.day}, month:{dt.month}, year:{dt.year}')
+          except ValueError:
+              output_list.append(f'INVALID FORMAT: {date_str}')
+  return output_list
+
+
+
+def dates_binding(text):
+  '''
+  This is a function that binds together all the subcomponents of the dates identification, while also controlling for multiple, or zero date references
+  '''
+
+  try:
+
+      # capture the referred dates
+      identified_dates = extract_dates(text)
+
+      # we only accept for one date reference
+      if len(identified_dates) == 1:
+
+        formatted_dates = convert_dates(identified_dates)
+
+
+        # in case there is a wrong date format then return the appropriate code to prompt back the proper message
+        if 'INVALID FORMAT' in formatted_dates[0]:
+          return (0,'DATES','wrong_date_format')
+
+        else:
+          return formatted_dates
+
+      # in case of zero references return the appropriate code (to aid returning the correct prompt)
+      elif len(identified_dates) == 0:
+        return (0,'DATES','no_date')
+
+      # in case of more than one references return the appropriate code (to aid returning the correct prompt)
+      elif len(identified_dates) > 1:
+        return (0,'DATES','more_dates')
+
+      # in case of unexpected error return the appropriate code (to aid returning the correct prompt)
+      else:
+        return (0,'DATES','unknown_error')
+
+  except:
+      return (0,'DATES','unknown_error')