Snapshot

Module containing all classes and functions responsible for dealing with snapshots.

class snapshot.Snapshot(json_repr)

Snapshot of an object’s state in a particular point of time.

For now, it’s basically just a dict.

Parameters

json_repr (Dict[str, Any]) –

items()

Mimics the built-in dict.items() method.

Returns

Exactly the same result as a dict.items() would.

Return type

ItemsView[str, Any]

class snapshot.SnapshotDiff

Class representing the differences between two snapshots (instances of Snapshot class).

Contains 3 categories:

• what was modified (same keys, different values)

• what was added (new keys)

• what was deleted (old keys not present anymore)

snapshot.make_snapshot(obj)

Creates a snapshot from AttributesMixin instance.

Parameters

obj (dsw_sdk.common.attributes.AttributesMixin) – instance of class AttributesMixin

Returns

snapshot of obj state

Return type

snapshot.Snapshot

snapshot.snapshots_diff(old, new)

Compares two snapshots (assuming the first one is older and the second one is newer), returning attributes in which they differ.

Parameters

• old (snapshot.Snapshot) – former state of the object

• new (snapshot.Snapshot) – newer (current) state of the object

Returns

attributes that was added, changed or deleted

Return type

snapshot.SnapshotDiff