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The JSON data stored in CPS can be retrieved as Maps, And using this we can find the delta between two anchors retrieved as two separate Maps. The result can be stored in an JSON array with appropriate notations for action, xpath and payload. The following algorithm can be used to find the difference between the two maps and also recursively finds the difference between the child data nodes. The response is in form of a JSON Array which closely represents the JSON Patch format as described above.

Algorithm:

1. Create an empty JSON Array, to store the result
   • The JSON array will contain the following: action, xpath, payload as individual JSON objects each object representing a singular operation.
2. Fetch the data from two anchors and store in two separate Maps
3. Iterate over the entries of first map
4. For each entry of first map, check if the key is present in second map.
5. If the key is not found in second map, it means that the key-value pair has been removed from the second map. Create a JSON Object with DELETE action, the xpath to deleted node and payload. Add the Object to the JSON Array.
6. If the key is present in the second map, compare the values associated with the keys in both maps.
7. If the values are instance of Map, recursively call the comparision algorithm to compare all nested maps. Add all the necessary fields into a JSON object and put the object into the JSON Array
8. If the values are not equal, it means the key-value pair was updated. Create a JSON Object with UPDATE action, the xpath to updated nodes and payload. Add the Object to the JSON Array.
9. Iterate over the keys of second map and find the keys not present in first map. These keys were added as new entries. Create a JSON Object with ADD action, the xpath to added node and payload. Add the Object to the JSON Array.
10. Return the JSON Array