Full text support in peewee

Adds support for full text search in peewee with the creation of two new field types: `FullIndexedCharField` and `FullIndexedTextField`.

Note that this change depends upon https://github.com/zzzeek/sqlalchemy/pull/339

[Delivers #137453279]
[Delivers #137453317]

data/fields.py

@@ -2,7 +2,8 @@ import base64
 import resumablehashlib
 import json
 
-from peewee import TextField
+from peewee import TextField, CharField, Clause
+from data.text import prefix_search
 
 
 class _ResumableSHAField(TextField):
@@ -64,3 +65,44 @@ class Base64BinaryField(TextField):
     if value is None:
       return None
     return base64.b64decode(value)
+
+
+def _add_fulltext(field_class):
+  """ Adds support for full text indexing and lookup to the given field class. """
+  class indexed_class(field_class):
+    # Marker used by SQLAlchemy translation layer to add the proper index for full text searching.
+    __fulltext__ = True
+
+    def __init__(self, match_function, *args, **kwargs):
+      field_class.__init__(self, *args, **kwargs)
+      self.match_function = match_function
+
+    def match(self, query):
+      return self.match_function(self, query)
+
+    def match_prefix(self, query):
+      return prefix_search(self, query)
+
+    def __mod__(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+    def __pow__(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+    def __contains__(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+    def contains(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+    def startswith(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+    def endswith(self, _):
+      raise Exception('Unsafe operation: Use `match` or `match_prefix`')
+
+  return indexed_class
+
+
+FullIndexedCharField = _add_fulltext(CharField)
+FullIndexedTextField = _add_fulltext(TextField)