Try to make package_dictize_with_revisions backwards compatible

ckan/migration/revision_legacy_code.py

@@ -35,17 +35,25 @@ def package_dictize_with_revisions(pkg, context):
     * the specified revision_id doesn't exist
     * the specified revision_date was before the package was created
     '''
+    try:
+        model.PackageRevision
+        # CKAN<=2.8
+        revision_model = model
+    except AttributeError:
+        # CKAN>2.8
+        revision_model = RevisionTableMappings.instance()
+
     model = context['model']
     is_latest_revision = not(context.get(u'revision_id') or
                              context.get(u'revision_date'))
     execute = _execute if is_latest_revision else _execute_with_revision
     # package
     if is_latest_revision:
-        if isinstance(pkg, RevisionTableMappings.instance().PackageRevision):
+        if isinstance(pkg, revision_model.PackageRevision):
             pkg = model.Package.get(pkg.id)
         result = pkg
     else:
-        package_rev = RevisionTableMappings.instance().package_revision_table
+        package_rev = revision_model.package_revision_table
         q = select([package_rev]).where(package_rev.c.id == pkg.id)
         result = execute(q, package_rev, context).first()
     if not result:
@@ -59,7 +67,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         res = model.resource_table
     else:
-        res = RevisionTableMappings.instance().resource_revision_table
+        res = revision_model.resource_revision_table
     q = select([res]).where(res.c.package_id == pkg.id)
     result = execute(q, res, context)
     result_dict["resources"] = resource_list_dictize(result, context)
@@ -70,7 +78,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         pkg_tag = model.package_tag_table
     else:
-        pkg_tag = RevisionTableMappings.instance().package_tag_revision_table
+        pkg_tag = revision_model.package_tag_revision_table
     q = select([tag, pkg_tag.c.state],
                from_obj=pkg_tag.join(tag, tag.c.id == pkg_tag.c.tag_id)
                ).where(pkg_tag.c.package_id == pkg.id)
@@ -90,7 +98,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         extra = model.package_extra_table
     else:
-        extra = RevisionTableMappings.instance().package_extra_revision_table
+        extra = revision_model.package_extra_revision_table
     q = select([extra]).where(extra.c.package_id == pkg.id)
     result = execute(q, extra, context)
     result_dict["extras"] = extras_list_dictize(result, context)
@@ -99,7 +107,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         member = model.member_table
     else:
-        member = RevisionTableMappings.instance().member_revision_table
+        member = revision_model.member_revision_table
     group = model.group_table
     q = select([group, member.c.capacity],
                from_obj=member.join(group, group.c.id == member.c.group_id)
@@ -118,7 +126,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         group = model.group_table
     else:
-        group = RevisionTableMappings.instance().group_revision_table
+        group = revision_model.group_revision_table
     q = select([group]
                ).where(group.c.id == result_dict['owner_org']) \
                 .where(group.c.state == u'active')
@@ -133,7 +141,7 @@ def package_dictize_with_revisions(pkg, context):
     if is_latest_revision:
         rel = model.package_relationship_table
     else:
-        rel = RevisionTableMappings.instance() \
+        rel = revision_model \
             .package_relationship_revision_table
     q = select([rel]).where(rel.c.subject_package_id == pkg.id)
     result = execute(q, rel, context)
@@ -195,7 +203,7 @@ def _execute_with_revision(q, rev_table, context):
     revision_date = context.get(u'revision_date')
 
     if revision_id:
-        revision = session.query(RevisionTableMappings.instance().Revision) \
+        revision = session.query(revision_model.Revision) \
             .filter_by(id=revision_id).first()
         if not revision:
             raise logic.NotFound