This module calculates parameterized query hash, which is a way to hash an incoming query (after resolving variables) with all leaf nodes (i.e. scalar values) discarded. In other words, two queries having the same parameterized query hash are essentially the same query but may differ in leaf values.

For example:

1. query { authors (where: {id: {_eq: 2}}) { id name } }
2. query { authors (where: {id: {_eq: 203943}}) { id name } }
3. query { authors (where: {id: {_eq: $id}}) { id name } }

For any value of id

1. query { authors (where: $whereBoolExp) { id name } }

only when whereBoolExp is of the form of

{ "id": { "_eq": id } }

All the above queries should result in the same parameterized query hash.

The following steps are done to calculate the parameterized query hash:

1. Normalize the GraphQL query by substituting the variables (if any) in appropriate places.
2. Substitute any scalar GraphQL values (Int, Float, Enum, String and Boolean) to null
3. For input objects and list, traverse through them and do step no 2.
4. Calculate the hash of the query obtained from step 3.

Note: Parameterized query hash is a PRO only feature