## Changes
DABs deployments should be isolated if `root_path` and workspace host
are different. This PR fixes a bug where local terraform state gets
piggybacked if the same cwd is used to deploy two isolated deployments
for the same bundle target. This can happen if:
1. A user switches to a different identity on the same machine.
2. The workspace host URL the bundle/target points to is changed.
3. A user changes the `root_path` while doing bundle development.
To solve this problem we rely on the lineage field available in the
terraform state, which is a uuid identifying unique terraform
deployments. There's a 1:1 mapping between a terraform deployment and a
bundle deployment.
For more details on how lineage works in terraform, see:
https://developer.hashicorp.com/terraform/language/state/backends#manual-state-pull-push
## Tests
Manually verified that changing the identity no longer results in the
incorrect terraform state being used. Also, new unit tests are added.
`terraform show -json` (`terraform.Show()`) fails if the state file
contains resources with fields that non longer conform to the provider
schemas.
This can happen when you deploy a bundle with one version of the CLI,
then updated the CLI to a version that uses different databricks
terraform provider, and try to run `bundle run` or `bundle summary`.
Those commands don't recreate local terraform state (only `terraform
apply` or `plan` do) and terraform itself fails while parsing it.
[Terraform
docs](https://developer.hashicorp.com/terraform/language/state#format)
point out that it's best to use `terraform show` after successful
`apply` or `plan`.
Here we parse the state ourselves. The state file format is internal to
terraform, but it's more stable than our resource schemas. We only parse
a subset of fields from the state, and only update ID and ModifiedStatus
of bundle resources in the `terraform.Load` mutator.
## Changes
When local state file exists it won't be override by remote state file
## Tests
Running `bricks bundle deploy` after state push failed does not override
local state file
Use cases verified:
1. Local state file is newer than remote
2. Local state file is older than remote
3. Local state file does not exist
4. Local state file corrupted
Pieter Noordhuis
shreyas-goenka
Ilia Babanov
Andrew Nester