This document was previously copied to the "Extending Terraform" section (in the
terraform-website repo), and the old URL was redirected so that the copy in
/guides can no longer be reached on the website. But the old copy of the file
remained, and now it runs the risk of confusing contributors, since the copy in
terraform-website/.../docs/extend is the more up-to-date version.
* command/show: added test scaffold for json output
More test cases will be added once the basic shape of the tests is
validated.
- command/json* packages now sort resources by address, matching
behavior elsewhere
- using cmp in tests instead of reflect.DeepEqual for the diffs
- updating expected output in tests to match sorting
Provider tests often rely on checking values contained within sets, by
directly accessing their flatmapped representation. In order to provider
the test harness with the expected set hashes, the sets must be
generated by the schema.Resource itself.
During the test we now build a fixed map of the providers, which should
only contain schema.Provider instances, and pass them into each
TestStep. The individual schema.Resource instances can then be pulled
from the providers, and used to recreate the state from the cty.Value
returned by the core operations.
Stricter type handling in the new shims may add empty containers into
the state where they were previously elided. Since the detection of
missing and empty containers in the legacy state was never reliable,
allow TestCheckNoResourceAttr to succeed if the key is a container count
index, and the value is "0"
The AWS Go SDK automatically provides a default request retryer with exponential backoff that is invoked via setting `MaxRetries` or leaving it `nil` will default to 3. The terraform-aws-provider `config.Client()` sets `MaxRetries` to 0 unless explicitly configured above 0. Previously, we were not overriding this behavior by setting the configuration and therefore not invoking the default request retryer.
The default retryer already handles HTTP error codes above 500, including S3's InternalError response, so the extraneous handling can be removed. This will also start automatically retrying many additional cases, such as temporary networking issues or other retryable AWS service responses.
Changes:
* s3/backend: Add `max_retries` argument
* s3/backend: Enhance S3 NoSuchBucket error to include additional information
Missing containers were often erroneously kept in the state, but since
the addition of the new provider shims, they can often be correctly
eliminated. There are however many tests that check for a "0" count in
the flatmap state when there shouldn't be a key at all. This addition
looks for a container count key and "0" pair, and allows for the key to
be missing.
There may be some tests negatively effected by this which were
legitimately checking for empty containers, but those were also not
reliably detected, and there should be much fewer tests involved.
Zero values and empty containers can be lost during the shimming
process, and during the provider's Apply step.
If we have known zero value containers and primitives in the source,
which appear as null values in the destination, we copy over the zero
value. Sets (and lists to an extent) are more difficult, since there
before and after indexes may not correlate. In that case we take the
entire container if it's wholly known, expecting the provider to have
correctly handled the value.
If a flatmap value has a count of 1 and no other attributes, it usually
indicates the equivalent configuration of an empty (or default value)
set block. Treat this as containing a single zero value object and
insert that into the set.
Due to incorrect use of a loop iterator variable inside a closure, all of
the given providers were ending up with the same factory function.
Now we copy the factory function to a local within the loop first so that
each iteration has its own variable.
This is the second round of similar bugs in this function, so we'll also
add a test case for it to reduce the risk of future regressions given that
most real callers don't exercise this with multiple providers in practice.
We missed this one on a previous pass of bringing in most of the cty
stdlib functions.
This will resolve#17625 by allowing conversion from Terraform's
conventional RFC 3339 timestamps into various other formats.
We use a shim to convert from the new state model back to the old because
the provider test API is still using the old API throughout. However, the
shim was not preserving the schema version recorded in the new-style state
and so a round-trip through this shim would cause the schema versions to
all revert to zero.
This can cause trouble with the destroy phase of provider tests because
(for API legacy reasons) we round-trip from old state back to new again
before the destroy phase and thus causing the providers to try to upgrade
from state version zero even though the data was already latest, which
can cause errors because state upgrades are generally not idempotent.
With the introduction of explicit "null" in 0.12 it's possible for a value
that is unknown during plan to become a known null during apply, so we
need to slightly weaken our validation rules to accommodate that, in
particular skipping the validation of conflicting attributes if the result
could potentially be valid after the unknown values become known.
This change is in the codepath that is common to both 0.12 and 0.11
callers, but that's safe because 0.11 re-runs validation during the apply
step and so will still catch problems here, albeit in the apply step
rather than in the plan step, thus matching the 0.12 behavior. This new
behavior is a superset of the old in the sense that everything that was
valid before is still valid.
The implementation here also causes us to skip all other validation for
an attribute whose value is unknown. Most of the downstream validation
functions handle this directly anyway, but again this doesn't add any new
failure cases, and should clean up some of the rough edges we've seen with
unknown values in 0.11 once people upgrade to 0.12-compatible providers.
Any issues we now short-circuit during planning will still be caught
during apply.
While working on this I found that the existing "Not a list" test was not
actually testing the correct behavior, so this also includes a tweak to
that to ensure that it really is checking the "should be a list" path
rather than the "cannot be set" codepath it was inadvertently testing
before.
This function is similar to the template_file data source offered by the
template provider, but having it built in to the language makes it more
convenient to use, allowing templates to be rendered from files anywhere
an inline template would normally be allowed:
user_data = templatefile("${path.module}/userdata.tmpl", {
hostname = format("petserver%02d", count.index)
})
Unlike the template_file data source, this function allows values of any
type in its variables map, passing them through verbatim to the template.
Its tighter integration with Terraform also allows it to return better
error messages with source location information from the template itself.
The template_file data source was originally created to work around the
fact that HIL didn't have any support for map values at the time, and
even once map support was added it wasn't very usable. With HCL2
expressions, there's little reason left to use a data source to render
a template; the only remaining reason left to use template_file is to
render a template that is constructed dynamically during the Terraform
run, which is a very rare need.
Nick Fagerlund