This is a new part of the existing module_variable_optional_attrs
experiment, because it's intended to complement the ability to declare
an input variable whose type constraint is an object type with optional
attributes. Module authors can use this to replace null values (that were
either explicitly set or implied by attribute omission) with other
non-null values of the same type.
This function is a bit more type-fussy than our functions typically are
because it's intended for use primarily with input variables that have
fully-specified type constraints, and thus it uses that type information
to help inform how the defaults data structure should be interpreted.
Other uses of this function will probably be harder today because it takes
a lot of extra annotation to build a value of a specific type if it isn't
passing through a variable type constraint. Perhaps later language
features for more general type conversion will make this more applicable,
but for now the more general form of this problem is better solved other
ways.
Prior to Terraform 0.12 these two functions were the only way to construct
literal lists and maps (respectively) in HIL expressions. Terraform 0.12,
by switching to HCL 2, introduced first-class syntax for constructing
tuple and object values, which can then be converted into list and map
values using the tolist and tomap type conversion functions.
We marked both of these functions as deprecated in the Terraform v0.12
release and have since then mentioned in the docs that they will be
removed in a future Terraform version. The "terraform 0.12upgrade" tool
from Terraform v0.12 also included a rule to automatically rewrite uses
of these functions into equivalent new syntax.
The main motivation for removing these now is just to get this change made
prior to Terraform 1.0. as we'll be doing with various other deprecations.
However, a specific reason for these two functions in particular is that
their existence is what caused us to invent the idea of a "type expression"
as a distinct kind of expression in Terraform v0.12, and so removing them
now would allow potentially unifying type expressions with value
expressions in a future release.
We do not have any current specific plans to make that change, but one
potential motivation for doing so would be to take another attempt at a
generalized "convert" function which takes a type as one of its arguments.
Our previous attempt to implement such a function was foiled by the fact
that Terraform's expression validator doesn't have any way to know to
treat one argument of a particular function as special, and so it was
generating incorrect error messages. We won't necessarily do that, but
having these "list" and "map" functions out of the way leaves the option
open.
This is an analog to the "alltrue" function, using OR as the reduce
operator rather than AND.
This also includes some simplification of the "alltrue" implementation
to implement it similarly as a sort of reduce operation with AND
as the reduce operator, but with the same effective behavior.
These were initially introduced as functions with "encode" and "decode"
prefixes, but that doesn't match with our existing convention of putting
the encoding format first so that the encode and decode functions will
group together in a alphabetically-ordered function list.
"text" is not really a defined serialization format, but it's a short word
that hopefully represents well enough what these functions are aiming to
encode and decode, while being consistent with existing functions like
jsonencode/jsondecode, yamlencode/yamldecode, etc.
The "base64" at the end here is less convincing because there is precedent
for that modifier to appear both at the beginning and the end in our
existing function names. I chose to put it at the end here because that
seems to be our emergent convention for situations where the base64
encoding is a sort of secondary modifier alongside the primary purpose
of the function, as we see with "filebase64". (base64gzip is an exception
here, but it seems outvoted by the others.)
This commit adds an `alltrue` function to Terraform configuration. A
reason we might want this function is because it will enable more
powerful custom variable validations. For example:
```hcl
variable "amis" {
type = list(object({
id = string
}))
validation {
condition = (alltrue([
for a in var.amis : length(a.id) > 4 && substr(a.id, 0, 4) == "ami-"
]))
error_message = "The ID of at least one AMI was invalid."
}
}
```
The encoding/json package escapes some HTML-specific characters to
prevent JSON from being misinterpreted when in the context of an HTML
document. Terraform 0.11 used this behaviour, and to preserve backwards
compatibility we are continuing to do so moving forward.
This commit adds an explicit test to document that this is intentional,
not a bug.
* add setdifference and setsubtract functions and docs
* remove setdifference as it is not implemented correct in underlying lib
* Update setintersection.html.md
* Update setproduct.html.md
* Update setunion.html.md
These are intended to make it easier to work with arbitrary data
structures whose shape might not be known statically, such as the result
of jsondecode(...) or yamldecode(...) of data from a separate system.
For example, in an object value which has attributes that may or may not
be set we can concisely provide a fallback value to use when the attribute
isn't set:
try(local.example.foo, "fallback-foo")
Using a "try to evaluate" model rather than explicit testing fits better
with the usual programming model of the Terraform language where values
are normally automatically converted to the necessary type where possible:
the given expression is subject to all of the same normal type conversions,
which avoids inadvertently creating a more restrictive evaluation model
as might happen if this were handled using checks like a hypothetical
isobject(...) function, etc.
Previously we were using the experimental HCL 2 repository, but now we'll
shift over to the v2 import path within the main HCL repository as part of
actually releasing HCL 2.0 as stable.
This is a mechanical search/replace to the new import paths. It also
switches to the v2.0.0 release of HCL, which includes some new code that
Terraform didn't previously have but should not change any behavior that
matters for Terraform's purposes.
For the moment the experimental HCL2 repository is still an indirect
dependency via terraform-config-inspect, so it remains in our go.sum and
vendor directories for the moment. Because terraform-config-inspect uses
a much smaller subset of the HCL2 functionality, this does still manage
to prune the vendor directory a little. A subsequent release of
terraform-config-inspect should allow us to completely remove that old
repository in a future commit.
This is a companion to cidrsubnet that allows bulk-allocation of multiple
subnet addresses at once, with automatic numbering.
Unlike cidrsubnet, cidrsubnets allows each of the allocations to have a
different prefix length, and will pack the networks consecutively into the
given address space. cidrsubnets can potentially create more complicated
addressing schemes than cidrsubnet alone can, because it's able to take
into account the full set of requested prefix lengths rather than just
one at a time.
Reference: https://github.com/hashicorp/terraform/issues/16697
Enumerates a set of regular file names from a given glob pattern. Implemented via the Go stdlib `path/filepath.Glob()` functionality. Notably, stdlib does not support `**` or `{}` extended patterns. See also: https://github.com/golang/go/issues/11862
To support the extended glob patterns, it will require adding a dependency on a third party library or adding our own matching code.
These existing upstream cty functions allow matching strings against
regular expression patterns, which can be useful if you need to consume
a non-standard string format that Terraform doesn't (and can't) have a
built-in function for.
These follow the same principle as jsondecode and jsonencode, but use
YAML instead of JSON.
YAML has a much more complex information model than JSON, so we can only
support a subset of it during decoding, but hopefully the subset supported
here is a useful one.
Because there are many different ways to _generate_ YAML, the yamlencode
function is forced to make some decisions, and those decisions are likely
to affect compatibility with other real-world YAML parsers. Although the
format here is intended to be generic and compatible, we may find that
there are problems with it that'll we'll want to adjust for in a future
release, so yamlencode is therefore marked as experimental for now until
the underlying library is ready to commit to ongoing byte-for-byte
compatibility in serialization.
The main use-case here is met by yamldecode, which will allow reading in
files written in YAML format by humans for use in Terraform modules, in
situations where a higher-level input format than direct Terraform
language declarations is helpful.
This is similar to the function of the same name in Python, generating a
sequence of numbers as a list that can then be used in other
sequence-oriented operations.
The primary use-case for it is to turn a count expressed as a number into
a list of that length, which can then be iterated over or passed to a
collection function to produce that number of something else, as shown
in the example at the end of its documentation page.
Added higher-level test for matchkeys to exercise mixing
types in searchset. This had to be in the functions tests so the HCL
auto conversion from tuple to list would occur.
* lang/funcs: testing of functions through the lang package API
The function-specific unit tests do not cover the HCL conversion that happens when the functions are called in a terraform configuration. For e.g., HCL converts sets to lists before passing it to the function. This means that we could not test passing a set in the function _unit_ tests.
This adds a higher-level acceptance test, plus a check that every (pure) function has a test.
* website/docs: update function documentation
Martin Atkins