## Changes
With https://github.com/databricks/cli/pull/1507 and
https://github.com/databricks/cli/pull/1511 we are clarifying the
semantics associated with `dyn.InvalidValue` and `dyn.NilValue`. An
invalid value is the default zero value and is used to signals the
complete absence of the value.
A nil value, on the other hand, is a valid value for a piece of
configuration and signals explicitly setting a key to nil in the
configuration tree. In keeping with that theme, this PR returns
`dyn.InvalidValue` instead of `dyn.NilValue` at error sites. This change
is not expected to have a material change in behaviour and is being done
to set the right convention since we have well-defined semantics
associated with both `NilValue` and `InvalidValue`.
## Tests
Unit tests and integration tests pass. Also manually scanned the changes
and the associated call sites to verify the `NilValue` value itself was
not being relied upon.
## Changes
This builds on #1098 and uses the `dyn.Value` representation of the
bundle configuration to generate the Terraform JSON definition of
resources in the bundle.
The existing code (in `BundleToTerraform`) was not great and in an
effort to slightly improve this, I added a package `tfdyn` that includes
dedicated files for each resource type. Every resource type has its own
conversion type that takes the `dyn.Value` of the bundle-side resource
and converts it into Terraform resources (e.g. a job and optionally its
permissions).
Because we now use a `dyn.Value` as input, we can represent and emit
zero-values that have so far been omitted. For example, setting
`num_workers: 0` in your bundle configuration now propagates all the way
to the Terraform JSON definition.
## Tests
* Unit tests for every converter. I reused the test inputs from
`convert_test.go`.
* Equivalence tests in every existing test case checks that the
resulting JSON is identical.
* I manually compared the TF JSON file generated by the CLI from the
main branch and from this PR on all of our bundles and bundle examples
(internal and external) and found the output doesn't change (with the
exception of the odd zero-value being included by the version in this
PR).