Support for Jolt-like "&" and "@" wildcards/operators for shift

[jeffneely]

It doesn't seem like Kazaam supports some of the wildcard functionality that Jolt offers in terms of the shift operation...

As an example, here is a Jolt shift spec:

  {
    "operation": "shift",
    "spec": {
      "job": {
        "task": {
          "*": {
            "query": {
              "*": {
                "name": "tasks[&3].queries[&1].query",
                "enabled": "tasks[&3].queries[&1].query_enabled",
                "@(2,name)": "tasks[&3].queries[&1].task_name",
                "@(4,name)": "tasks[&3].queries[&1].job_name"
              }
            }
          }
        }
      }
    }
 }

Specifically:
"&" - references key values captured by a walked wildcard "*" path to get a value
Example:

{
    "foo" : {
        "bar": {
            "baz":  // &0 = baz, &1 = bar, &2 = foo
        }
    }
}

"@" - reference another key by name in a walked wildcard "*" path
Example: "@(3,title)"
"3" means go up the tree 3 levels and then lookup the key "title" and use the value at that key

Any plans to support these?

[yxuco]

Isn't the spec of this package reversed from Jolt? Jolt spec maps from input field to output field path, while kazaam maps output field to input field path. Would this change make it harder to introduce iterative wildcard "*", or to create a new array based on an input array? For example, the following Jolt spec would create a new array photos[] from an input array Photos[]. Can Kazaam do something similar?

	spec := `{
        "Photos": {
            "*": {
                "Id": "photos[&1].id",
                "Caption": "photos[&1].caption",
                "Sizes": {
                    "*": {
                        "Url": "photos[&3].sizes.&1"
                    }
                },
                "SizesOrder": "photos[&1].sizesOrder"
            }
        }
    }`