.

go/zodb/pyserialize.go

+// Copyright (C) 2016-2017  Nexedi SA and Contributors.
+//                          Kirill Smelkov <kirr@nexedi.com>
+//
+// This program is free software: you can Use, Study, Modify and Redistribute
+// it under the terms of the GNU General Public License version 3, or (at your
+// option) any later version, as published by the Free Software Foundation.
+//
+// You can also Link and Combine this program with other software covered by
+// the terms of any of the Free Software licenses or any of the Open Source
+// Initiative approved licenses and Convey the resulting work. Corresponding
+// source of such a combination shall include the source code for all other
+// software used.
+//
+// This program is distributed WITHOUT ANY WARRANTY; without even the implied
+// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+//
+// See COPYING file for full licensing terms.
+// See https://www.nexedi.com/licensing for rationale and options.
+
+package zodb
+// serialization compatibility with ZODB/py
+
+import (
+	"bytes"
+	"fmt"
+
+	pickle "github.com/kisielk/og-rek"
+)
+
+// PyData represent data stored into ZODB by Python applications.
+//
+// The format is based on python pickles. Basically every sirialized object has
+// two parts: class description and object state. See
+//
+//	https://github.com/zopefoundation/ZODB/blob/a89485c1/src/ZODB/serialize.py
+//
+// for format description.
+type PyData []byte
+
+// ClassString returns fully-qualified python class name used for object type
+// The format is "module.class"
+// If pickle decoding fails "?.?" is returned.
+// TODO tests
+func (d PyData) ClassString() string {
+	// see ObjectReader.getClassName & get_pickle_metadata in zodb/py
+	p := pickle.NewDecoder(bytes.NewReader([]byte(d)))
+	xklass, err := p.Decode()
+	if err != nil {
+		return "?.?"
+	}
+
+	if t, ok := xklass.(pickle.Tuple); ok {
+		if len(t) != 2 {	// (klass, args)
+			return "?.?"
+		}
+		xklass = t[0]
+		if t, ok := xklass.(pickle.Tuple); ok {
+			// py: "old style reference"
+			if len(t) != 2 {
+				return "?.?"	// (modname, classname)
+			}
+			return fmt.Sprintf("%s.%s", t...)
+		}
+	}
+
+	if klass, ok := xklass.(pickle.Class); ok {
+		return klass.Module + "." + klass.Name
+	}
+
+	return "?.?"
+}

go/zodb/storage/fs1/fs1tools/dump.go

@@ -28,6 +28,7 @@ import (
 	"log"
 	"os"
 
+	"lab.nexedi.com/kirr/neo/go/zodb"
 	"lab.nexedi.com/kirr/neo/go/zodb/storage/fs1"
 
 	"lab.nexedi.com/kirr/go123/xbytes"
@@ -183,9 +184,7 @@ func (d *DumperFsDump) DumpTxn(buf *xfmt.Buffer, it *fs1.Iter) error {
 		if data == nil {
 			buf .S(" class=undo or abort of object creation")
 		} else {
-			//modname, classname = zodb.GetPickleMetadata(...)	// XXX
-			//fullclass = "%s.%s" % (modname, classname)
-			fullclass := "AAA.BBB"	// FIXME stub
+			fullclass := zodb.PyData(data).ClassString()
 
 			buf .S(" size=") .D64(dh.DataLen)
 			buf .S(" class=") .S(fullclass)