add migration for upcoming change to tiger tables

[nominatim.git] / nominatim / tokenizer / base.py

diff --git a/nominatim/tokenizer/base.py b/nominatim/tokenizer/base.py
index 94fac1fc4e1cdcab553af27f6fe1a94b21a9f95f..f81b3bc262ed9f690b0eb6bc794e2cab076de822 100644 (file)
--- a/nominatim/tokenizer/base.py
+++ b/nominatim/tokenizer/base.py
@@ -1,3 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2022 by the Nominatim developer community.
+# For a full list of authors see the git log.
 """
 Abstract class defintions for tokenizers. These base classes are here
 mainly for documentation purposes.
@@ -30,7 +36,6 @@ class AbstractAnalyzer(ABC):
     def close(self) -> None:
         """ Free all resources used by the analyzer.
         """
-        pass
 
 
     @abstractmethod
@@ -50,7 +55,6 @@ class AbstractAnalyzer(ABC):
                 found for the given words. Each list entry is a tuple of
                 (original word, word token, word id).
         """
-        pass
 
 
     @abstractmethod
@@ -66,7 +70,6 @@ class AbstractAnalyzer(ABC):
             Returns:
                 The given postcode after normalization.
         """
-        pass
 
 
     @abstractmethod
@@ -74,7 +77,6 @@ class AbstractAnalyzer(ABC):
         """ Update the tokenizer's postcode tokens from the current content
             of the `location_postcode` table.
         """
-        pass
 
 
     @abstractmethod
@@ -90,7 +92,6 @@ class AbstractAnalyzer(ABC):
                                 When false, just add the given phrases to the
                                 ones that already exist.
         """
-        pass
 
 
     @abstractmethod
@@ -102,7 +103,6 @@ class AbstractAnalyzer(ABC):
                               refer to.
                 names: Dictionary of name type to name.
         """
-        pass
 
 
     @abstractmethod
@@ -145,7 +145,6 @@ class AbstractTokenizer(ABC):
 
             TODO: can we move the init_db parameter somewhere else?
         """
-        pass
 
 
     @abstractmethod
@@ -158,7 +157,6 @@ class AbstractTokenizer(ABC):
             Arguments:
               config: Read-only object with configuration options.
         """
-        pass
 
 
     @abstractmethod
@@ -171,7 +169,6 @@ class AbstractTokenizer(ABC):
             Arguments:
               config: Read-only object with configuration options.
         """
-        pass
 
 
     @abstractmethod
@@ -186,7 +183,6 @@ class AbstractTokenizer(ABC):
             Arguments:
               config: Read-only object with configuration options.
         """
-        pass
 
 
     @abstractmethod
@@ -202,7 +198,6 @@ class AbstractTokenizer(ABC):
               description of the issue as well as hints for the user on
               how to resolve the issue. If everything is okay, return `None`.
         """
-        pass
 
 
     @abstractmethod
@@ -212,7 +207,13 @@ class AbstractTokenizer(ABC):
             to improve performance. However, the tokenizer must not depend on
             it to be called in order to work.
         """
-        pass
+
+
+    @abstractmethod
+    def update_word_tokens(self) -> None:
+        """ Do house-keeping on the tokenizers internal data structures.
+            Remove unused word tokens, resort data etc.
+        """
 
 
     @abstractmethod
@@ -229,4 +230,3 @@ class AbstractTokenizer(ABC):
             When used outside the with construct, the caller must ensure to
             call the close() function before destructing the analyzer.
         """
-        pass