This is to avoid dependency sprawl - e.g. vendoring AWS or Azure SDK
when we don't really need remote backend functionality
in provider code - it's core's responsibility.
This is a rework of pull request #6213 submitted by @joshuaspence,
adjusted to work with the remote state data source. We also add
a deprecation warning for people using the unsupported API, and retain
the ability to refer to "_local" as well as "local" for users in a mixed
version environment.
The template resources don't actually need to retain any state, so they
are good candidates to be data sources.
This includes a few tweaks to the acceptance tests -- now configured to
run as unit tests -- since it seems that they have been slightly broken
for a while now. In particular, the "update" cases are no longer tested
because updating is not a meaningful operation for a data source.
I noticed we had two mechanisms for unit test override. One that dropped
a sentinel into the env var, and another with a struct member on
TestCase. This consolidates the two, using the cleaner struct member
internal mechanism and the nicer `resource.UnitTest()` entry point.
The work integrated in hashicorp/terraform#6322 silently broke the
ability to use remote state correctly. This commit adds a fix for that,
making use of the work integrated in hashicorp/terraform#7124.
In order to deal with outputs which are complex structures, we use a
forked version of the flatmap package - the difference in the version
this commit vs the github.com/hashicorp/terraform/flatmap package is
that we add in an additional key for map counts which state requires.
Because we bypass the normal helper/schema mechanism, this is not set
for us.
Because of the HIL type checking of maps, values must be of a homogenous
type. This is unfortunate, as it means we can no longer refer to outputs
as:
${terraform_remote_state.foo.output.outputname}
Instead we had to bring them to the top level namespace:
${terraform_remote_state.foo.outputname}
This actually does lead to better overall usability - and the BC
breakage is made better by the fact that indexing would have broken the
original syntax anyway.
We also add a real-world test and assert against specific values. Tests
which were previously acceptance tests are now run as unit tests, so
regression should be identified at a much earlier stage.
This commit forward ports the changes made for 0.6.17, in order to store
the type and sensitive flag against outputs.
It also refactors the logic of the import for V0 to V1 state, and
fixes up the call sites of the new format for outputs in V2 state.
Finally we fix up tests which did not previously set a state version
where one is required.
As a first example of a real-world data source, the pre-existing
terraform_remote_state resource is adapted to be a data source. The
original resource is shimmed to wrap the data source for backward
compatibility.
For backward compatibility we will continue to support using the data
sources that were formerly logical resources as resources for the moment,
but we want to warn the user about it since this support is likely to
be removed in future.
This is done by adding a new "deprecation message" feature to
schema.Resource, but for the moment this is done as an internal feature
(not usable directly by plugins) so that we can collect additional
use-cases and design a more general interface before creating a
compatibility constraint.
