Best way of returning differences of two json files programatically

Question

I have two json files and I would like to get a json containing the differences. It is important that only the actual differences of

Answer 1

Basically, what you want is something similar to array_diff_assoc, but applied to json objects, and recursive.

The array_diff functions are not recursive because of reference issues: it is possible to assign a reference of an array to an entry of that array, making the array infinitely recursive. I don't think it is possible to get the same situation with a json object, thus making a recursive function safe.

Let's suppose that you wish to compute the difference between object A and B, and have the result in object C. The principle is to loop over each field of A (a foreach should do), and when:

• no such field exist in B, copy it over C.
• a similar field exist in B, put in C the result of the difference of A field with B field, which is a recursive call on the diff function with those field as parameter, as well as a fresh object for the result.

The ordering of A should be respected.