You can signal the same information in `Read` with an empty ID if the object does not exist, Implementing `Exists` is not the only way to do so and in some providers is also not the preferred way.
Notable changes (from Terraform AWS Provider CHANGELOG):
```
NOTES:
* backend/s3: Region validation now automatically supports the new `me-south-1` Middle East (Bahrain) region. For AWS operations to work in the new region, the region must be explicitly enabled as outlined in the [previous new region announcement blog post](https://aws.amazon.com/blogs/aws/now-open-aws-asia-pacific-hong-kong-region/). When the region is not enabled, the Terraform S3 Backend will return errors during credential validation (e.g. `error validating provider credentials: error calling sts:GetCallerIdentity: InvalidClientTokenId: The security token included in the request is invalid`).
* backend/s3: After this update, the AWS Go SDK will prefer credentials found via the `AWS_PROFILE` environment variable when both the `AWS_PROFILE` environment variable and the `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` environment variables are statically defined. Previously the SDK would ignore the `AWS_PROFILE` environment variable, if static environment credentials were also specified. This is listed as a bug fix in the AWS Go SDK release notes.
ENHANCEMENTS:
* backend/s3: Add support for assuming role via web identity token via the `AWS_WEB_IDENTITY_TOKEN_FILE` and `AWS_ROLE_ARN` environment variables
* backend/s3: Support automatic region validation for `me-south-1`
BUG FIXES:
* backend/s3: Load credentials via the `AWS_PROFILE` environment variable (if available) when `AWS_PROFILE` is defined along with `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`
```
Updated via:
```
go get github.com/aws/aws-sdk-go@v1.21.7
go mod tidy
go mod vendor
```
Verification with this update:
```hcl
terraform {
backend "s3" {
bucket = "me-south-1-testing"
key = "test"
region = "me-south-1"
}
}
output "test" {
value = timestamp()
}
```
Outputs:
```
$ terraform apply
Apply complete! Resources: 0 added, 0 changed, 0 destroyed.
Outputs:
test = 2019-07-30T12:49:19Z
```
If the new region is not properly enabled for the account, errors like the below will be received:
```
$ terraform init
Initializing the backend...
Error: error validating provider credentials: error calling sts:GetCallerIdentity: InvalidClientTokenId: The security token included in the request is invalid.
```
To use this region before this update:
```hcl
terraform {
# ... potentially other configuration ...
backend "s3" {
# ... other configuration ...
region = "me-south-1"
skip_region_validation = true
}
}
```
Nil values were not previously expected during validation, but they can
appear in some situations with the new protocol. Add checks to prevent
using zero reflect.Values.
If there are unknowns, the block may have come from a dynamic
declaration, and we can't validate MinItems. Once the blocks are
expanded, we will get the full config for validation without any unknown
values.
If a block was defined via "dynamic", there will be only one block value
until the expansion is known. Since we can't detect dynamic blocks at
this point, don't verify MinItems while there are unknown values in the
config.
The decoder spec can also only check for existence of a block, so limit
the check to 0 or 1.
This also fixes a few things with resource for_each:
It makes validation more like validation for count.
It makes sure the index is stored in the state properly.
In some cases (see #22020 for a specific example), the parsed hilNode
can be nil. This causes a series of panics. Instead, return an error and
move on.
* command/init: omit a warning if -backend-config is used with no backend
block
Terraform would silently accept - and swallow - `-backend-config` on the
CLI when there was no `backend` block. Since it is mostly expected to
override existing backend configuration, terraform
should omit a warning if there is no backend configuration to
override.
If the user intended to override the default (local) backend
configuration, they can first add a `backend` block to the `terraform` block to silence the warning (or just ignore it):
```hcl
terraform {
backend "local" {}
}
```
Mistakenly using dynamic on an attribute will lead to a panic when
attempting to resolve variable references with a partial body, because
the dynamic blocks have yet to be expanded and validated. Check that the
block element type is actually an object before generating a schema.
Previously, terraform was returning a potentially-misleading error
message in response to anything other than a 404 from the
b.client.Workspaces.Read operation. This PR simplifies Terraform's error
message with the intent of encouraging those who encounter it to focus
on the error message returned from the tfe client.
The added test is odd, and a bit hacky, and possibly overkill.
1) Mention the host and port in the "Connecting..." message.
2) Mention the username in the post-connection handshaking message.
3) If handshaking fails, mention the user, host, and port in the error
message that will eventually be returned to the user.
Some of our errors returned here were lacking context about what part of
the file was problematic, which led to some useless error reporting for
some real-world situations that this upgrade process doesn't seem to be
catching.
Here we add additional context to those error cases, as a step towards
tracking down exactly which upgrade cases are missing here so that we can
potentially fix them in a subsequent release.
Paul Tyng