[IMP] orm: iter_browse accept generator or query as ids

This allows the caller to be memory efficient on huge numbers of ids, allowing
for even more millions of records to be browsed.

Author: cawo-odoo

src/util/orm.py

@@ -11,6 +11,7 @@
 
 import logging
 import re
+import uuid
 from contextlib import contextmanager
 from functools import wraps
 from itertools import chain
@@ -374,7 +375,8 @@ class iter_browse(object):
 
     :param model: the model to iterate
     :type model: :class:`odoo.model.Model`
-    :param list(int) ids: list of IDs of the records to iterate
+    :param iterable(int) ids: iterable of IDs of the records to iterate
+    :param str query: alternative to ids, SQL query that can produce them
     :param int chunk_size: number of records to load in each iteration chunk, `200` by
                            default
     :param logger: logger used to report the progress, by default
@@ -387,23 +389,60 @@ class iter_browse(object):
     See also :func:`~odoo.upgrade.util.orm.env`
     """
 
-    __slots__ = ("_chunk_size", "_cr_uid", "_it", "_logger", "_model", "_patch", "_size", "_strategy")
+    __slots__ = ("_chunk_size", "_cr_uid", "_ids", "_it", "_logger", "_model", "_patch", "_query", "_size", "_strategy")
 
     def __init__(self, model, *args, **kw):
         assert len(args) in [1, 3]  # either (cr, uid, ids) or (ids,)
         self._model = model
         self._cr_uid = args[:-1]
-        ids = args[-1]
-        self._size = len(ids)
+        self._ids = args[-1]
+        self._size = kw.pop("size", None)
+        self._query = kw.pop("query", None)
         self._chunk_size = kw.pop("chunk_size", 200)  # keyword-only argument
         self._logger = kw.pop("logger", _logger)
         self._strategy = kw.pop("strategy", "flush")
         assert self._strategy in {"flush", "commit"}
         if kw:
             raise TypeError("Unknown arguments: %s" % ", ".join(kw))
 
+        if not bool(self._ids) ^ bool(self._query):
+            raise TypeError("Must be initialized using exactly one of `ids` or `query`")
+
+        if self._query:
+            self._ids_query()
+
+        if not self._size:
+            try:
+                self._size = len(self._ids)
+            except TypeError:
+                raise ValueError("When passing ids as a generator, the size kwarg is mandatory")
         self._patch = None
-        self._it = chunks(ids, self._chunk_size, fmt=self._browse)
+        self._it = chunks(self._ids, self._chunk_size, fmt=self._browse)
+
+    def _ids_query(self):
+        cr = self._model.env.cr
+        tmp_tbl = "_upgrade_ib_{}".format(uuid.uuid4().hex)
+        cr.execute(
+            format_query(
+                cr,
+                "CREATE UNLOGGED TABLE {}(id) AS (WITH query AS ({}) SELECT * FROM query)",
+                tmp_tbl,
+                SQLStr(self._query),
+            )
+        )
+        self._size = cr.rowcount
+        cr.execute(
+            format_query(cr, "ALTER TABLE {} ADD CONSTRAINT {} PRIMARY KEY (id)", tmp_tbl, "pk_{}_id".format(tmp_tbl))
+        )
+
+        def get_ids():
+            with named_cursor(cr, itersize=self._chunk_size) as ncr:
+                ncr.execute(format_query(cr, "SELECT id FROM {} ORDER BY id", tmp_tbl))
+                for (id_,) in ncr:
+                    yield id_
+            cr.execute(format_query(cr, "DROP TABLE IF EXISTS {}", tmp_tbl))
+
+        self._ids = get_ids()
 
     def _browse(self, ids):
         next(self._end(), None)