Ausgabe der neuen DB Einträge

venv/lib/python3.9/site-packages/scrapy/utils/trackref.py

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+"""This module provides some functions and classes to record and report
+references to live object instances.
+
+If you want live objects for a particular class to be tracked, you only have to
+subclass from object_ref (instead of object).
+
+About performance: This library has a minimal performance impact when enabled,
+and no performance penalty at all when disabled (as object_ref becomes just an
+alias to object in that case).
+"""
+
+import weakref
+from time import time
+from operator import itemgetter
+from collections import defaultdict
+
+
+NoneType = type(None)
+live_refs = defaultdict(weakref.WeakKeyDictionary)
+
+
+class object_ref:
+    """Inherit from this class to a keep a record of live instances"""
+
+    __slots__ = ()
+
+    def __new__(cls, *args, **kwargs):
+        obj = object.__new__(cls)
+        live_refs[cls][obj] = time()
+        return obj
+
+
+def format_live_refs(ignore=NoneType):
+    """Return a tabular representation of tracked objects"""
+    s = "Live References\n\n"
+    now = time()
+    for cls, wdict in sorted(live_refs.items(),
+                             key=lambda x: x[0].__name__):
+        if not wdict:
+            continue
+        if issubclass(cls, ignore):
+            continue
+        oldest = min(wdict.values())
+        s += f"{cls.__name__:<30} {len(wdict):6}   oldest: {int(now - oldest)}s ago\n"
+    return s
+
+
+def print_live_refs(*a, **kw):
+    """Print tracked objects"""
+    print(format_live_refs(*a, **kw))
+
+
+def get_oldest(class_name):
+    """Get the oldest object for a specific class name"""
+    for cls, wdict in live_refs.items():
+        if cls.__name__ == class_name:
+            if not wdict:
+                break
+            return min(wdict.items(), key=itemgetter(1))[0]
+
+
+def iter_all(class_name):
+    """Iterate over all objects of the same class by its class name"""
+    for cls, wdict in live_refs.items():
+        if cls.__name__ == class_name:
+            return wdict.keys()