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.
So far all of our language experiments have been new constructs handled
statically up in the configs package, but functions are another common
extention point where experiments could be useful to gather feedback and
so this intends to pass the information down into the right place to allow
for that to happen, even though as of this commit there are no
experimental functions to use it.
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.
Our diagnostics model allows for optionally annotating an error or warning
with information about the expression and eval context it was generated
from, which the diagnostic renderer for the UI will then use to give the
user some additional hints about what values may have contributed to the
error.
We previously didn't have those annotations on the results of evaluating
for_each expressions though, because in that case we were using the helper
function to evaluate an expression in one shot and thus we didn't ever
have a reference to the EvalContext in order to include it in the
diagnostic values.
Now, at the expense of having to handle the evaluation at a slightly lower
level of abstraction, we'll annotate all of the for_each error messages
with source expression information. This is valuable because we see users
often confused as to how their complex for_each expressions ended up being
invalid, and hopefully giving some information about what the inputs were
will allow more users to self-solve.
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.)
Fix for issue #26320 - this allows us to derive known values from
partially known maps where we can, and may prevent unnecessary
destroy/rebuild cycles during apply in some cases.
In order to properly evaluate a destroy provisioner, we cannot rely on
the usual evaluation context, because the resource has already been
removed from the state.
EvalSelfBlock evaluates an hcl.Body in the limited scope of a single
object as "self", with the added values of "count.index" and "each.key".
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.
The functions that interact with the filesystem are, by design, restricted
to reading files that are distributed as a static part of the
configuration, and cannot be used to interact with files that are
generated dynamically by resources in the configuration.
However, new users have often yet developed a correct mental model of how
Terraform execution works and are confused by the terse error messages
these functions return. As an interim step to help some of those users,
this just adds some more commentary to the error message which gives a
vague, generic directive to look to attributes of the resource that is
generating the file, which should (if it's designed well) export
attributes that allow the resulting file to be used effectively with
common patterns, such as checksums of the content of the generated file.
The error message here is not particularly attractive due to the
limitations of the context where it's being returned from, but I'm
accepting that here in the interest of keeping this change simple, so we
can give a hint about a case that seems to frequently generate new-user
questions. We may iterate further on the presentation of this message
later.
Previously this function only supported the x509 RSA private key format.
More recent versions of OpenSSH default to generating a new PEM key
format, which this commit now supports using the x/crypto/ssh package.
Also improve the returned error messages for various invalid ciphertext
or invalid private key errors.
There is no codepath that can use this any longer, since we need to
evaluate the modules as whole objects.
This means we're going to have to live for now with invalid module
output references returning "object" errors rather that "module".
In order to be able to use module values, and handle operations like
possibly invalid module indexes in conditional statements, whole modules
must always be returned during evaluation.
The map function assumed that the key arguments were strings, and would
panic if they were not.
After this commit, calling `map(1, 2)` will result in a map `{"1" = 1}`,
and calling `map(null, 1)` will result in a syntax error.
Fixes#23346, fixes#23043
Previously the templatefile function would permit any arbitrary string as
a variable name, but due to the HCL template syntax it would be impossible
to refer to one that isn't a valid HCL identifier without causing an
HCL syntax error.
The HCL syntax errors are correct, but don't really point to the root
cause of the problem. Instead, we'll pre-verify that the variable names
are valid before we even try to render the template, and given a
specialized error message that refers to the vars argument expression as
the problematic part, which will hopefully make the resolution path
clearer for a user encountering this situation.
The syntax error still remains for situations where all of the variable
names are correct but e.g. the user made a typo referring to one, which
makes sense because in that case the problem _is_ inside the template.
This function has a number of different error cases with hopefully-helpful
error messages for each, so it's good to test we're getting the error
message we were actually expecting in each case.
* 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
This PR implements 2 changes to the merge function.
- Rather than always defining the merge return type as dynamic, return
a precise type when all argument types match, or all possible object
attributes are known.
- Always return a value containing all keys when the keys are known.
This allows the use of merge output in for_each, even when keys are yet
to be determined.
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.
The fallback type for GetResource from an EachMap is a cty.Object,
because resource schemas may contain dynamically typed attributes.
Check for an Object type in the evaluation of self, to use the proper
GetAttr method when extracting the value.
self references do not need to be added to `managedResource`, and in
fact that could cause issues later if self is allowed in contexts other
than managed resources.
Coalesce 2 cases in the Referenceable switch, be take the
ContainingResource address of an instance beforehand.
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.
Continue only evaluating resource at a whole and push the indexing of
the resource down into the expression evaluation.
The exception here is that `self` must be an instance which must be
extracted from the resource. We now also add the entire resource to the
context, which was previously only partially populated with the self
referenced instance.
In order to allow lazy evaluation of resource indexes, we can't index
resources immediately via GetResourceInstance. Change the evaluation to
always return whole Resources via GetResource, and index individual
instances during expression evaluation.
This will allow us to always check for invalid index errors rather than
returning an unknown value and ignoring it during apply.
James Bardin