diffsync.helpers

DiffSync helper classes for calculating and performing diff and sync operations.

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Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

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diffsync.helpers.DiffSyncDiffer

Helper class implementing diff calculation logic for DiffSync.

Independent from Diff and DiffElement as those classes are purely data objects, while this stores some state.

__init__(src_diffsync, dst_diffsync, flags, diff_class=Diff, callback=None)

Create a DiffSyncDiffer for calculating diffs between the provided DiffSync instances.

calculate_diffs()

Calculate diffs between the src and dst DiffSync objects and return the resulting Diff.

diff_child_objects(diff_element, src_obj, dst_obj)

For all children of the given DiffSyncModel pair, diff recursively, adding diffs to the given diff_element.

Helper method to calculate_diffs, usually doesn't need to be called directly.

These helper methods work in a recursive cycle: diff_object_list -> diff_object_pair -> diff_child_objects -> diff_object_list -> etc.

diff_object_list(src, dst)

Calculate diffs between two lists of like objects.

Helper method to calculate_diffs, usually doesn't need to be called directly.

These helper methods work in a recursive cycle: diff_object_list -> diff_object_pair -> diff_child_objects -> diff_object_list -> etc.

diff_object_pair(src_obj, dst_obj)

Diff the two provided DiffSyncModel objects and return a DiffElement or None.

Helper method to calculate_diffs, usually doesn't need to be called directly.

These helper methods work in a recursive cycle: diff_object_list -> diff_object_pair -> diff_child_objects -> diff_object_list -> etc.

incr_models_processed(delta=1)

Increment self.models_processed, then call self.callback if present.

validate_objects_for_diff(object_pairs) staticmethod

Check whether all DiffSyncModels in the given dictionary are valid for comparison to one another.

Helper method for diff_object_list.

Raises:

Type	Description
TypeError	If any pair of objects in the dict have differing get_type() values.
ValueError	If any pair of objects in the dict have differing get_shortname() or get_identifiers() values.

diffsync.helpers.DiffSyncSyncer

Helper class implementing data synchronization logic for DiffSync.

Independent from DiffSync and DiffSyncModel as those classes are purely data objects, while this stores some state.

__init__(diff, src_diffsync, dst_diffsync, flags, callback=None)

Create a DiffSyncSyncer instance, ready to call perform_sync() against.

incr_elements_processed(delta=1)

Increment self.elements_processed, then call self.callback if present.

log_sync_status(action, status, message)

Log the current sync status at the appropriate verbosity with appropriate context.

Helper method to sync_diff_element/sync_model.

perform_sync()

Perform data synchronization based on the provided diff.

Returns:

Type	Description
bool	True if any changes were actually performed, else False.

sync_diff_element(element, parent_model=None)

Recursively synchronize the given DiffElement and its children, if any, into the dst_diffsync.

Helper method to perform_sync.

Returns:

Name	Type	Description
bool	bool	True if this element or any of its children resulted in actual changes, else False.

sync_model(src_model, dst_model, ids, attrs)

Create/update/delete the current DiffSyncModel with current ids/attrs, and update self.status and self.message.

Helper method to sync_diff_element.

Returns:

Type	Description
Tuple[bool, Optional[DiffSyncModel]]	(changed, model) where model may be None if an error occurred