This note is in Hasura.Function.API. It is referenced at:
Before we started supporting tracking volatile functions, permissions
for a function was inferred from the target table of the function.
The rationale behind this is that a stable/immutable function does not
modify the database and the data returned by the function is filtered using
the permissions that are specified precisely for that data.
Now consider mutable/volatile functions, we can’t automatically infer whether or
not these functions should be exposed for the sole reason that they can modify
the database. This necessitates a permission system for functions.
So, we introduce a new API pg_create_function_permission which will
explicitly grant permission to a function to a role. For creating a
function permission, the role must have select permissions configured
for the target table.
Since, this is a breaking change, we enable it only when the graphql-engine
is started with
--infer-function-permissions/HASURA_GRAPHQL_INFER_FUNCTION_PERMISSIONS set
to false (by default, it’s set to true).