When packer validate is invoked, it does not try to evaluate the
datasources before attempting to decide if the template is valid.
In many cases, this works, but sometimes it will fail as the value is
unknown by the validation code.
Since the validation code for all the elements of a Packer template is
left to be implemented by plugins, we cannot rely on checking for
unknown values everywhere, especially since the unknown references are
replaced automatically by a value of the right type for the
configuration expected.
So, in order for such configurations to be validable, we add an extra
option to packer validate, that will let users evaluate the datasources
from a template.
* Update validation options for undeclared variables
In an effort to help users move from JSON to HCL2 templates the support for
variable definitions files are being updated to ignore undeclared
variable warnings on build execution. For legacy JSON templates builds no
warnings are displayed when var-files contain undeclared variables.
Since preferred mode HCL2 templates is to be explicit with variable
declarations - they must be declared to be used - validation for
undeclared variables still warns when running `packer validate`. A new
flag has been added to the validate command that can be used to disable
undeclared variable warnings.
* Update validation test for unused variables
Example Run
```
~> go run . validate -no-warn-undeclared-var -var-file
command/test-fixtures/validate/var-file-tests/undeclared.pkrvars.hcl
command/test-fixtures/validate/var-file-tests/basic.pkr.hcl
The configuration is valid.
~> go run . validate -var-file
command/test-fixtures/validate/var-file-tests/undeclared.pkrvars.hcl
command/test-fixtures/validate/var-file-tests/basic.pkr.hcl
Warning: Undefined variable
The variable "unused" was set but was not declared as an input variable.
To declare variable "unused" place this block in one of your .pkr.hcl
files,
such as variables.pkr.hcl
variable "unused" {
type = string
default = null
}
The configuration is valid.
~> go run . build -var-file
command/test-fixtures/validate/var-file-tests/undeclared.pkrvars.hcl
command/test-fixtures/validate/var-file-tests/basic.pkr.hcl
file.chocolate: output will be in this color.
Build 'file.chocolate' finished after 744 microseconds.
==> Wait completed after 798 microseconds
==> Builds finished. The artifacts of successful builds are:
--> file.chocolate: Stored file: chocolate.txt
```
* Rename Strict field to WarnOnUndeclaredVar
The field name Strict is a bit vague since it is only used for
checking against undeclared variables within a var-file definition.
To mitigate against potential overloading of this field it is
being renamed to be more explicit on its usage.
* command/build: Add warn-on-undeclared-var flag
Now that the default behaviour is to not display warnings for undeclared variables
an optional flag has been added to toggle the old behaviour.
```
~> go run . build -warn-on-undeclared-var -var-file command/test-fixtures/validate/var-file-tests/undeclared.pkrvars.hcl command/test-fixtures/validate/var-file-tests/basic.pkr.hcl
Warning: Undefined variable
The variable "unused" was set but was not declared as an input variable.
To declare variable "unused" place this block in one of your .pkr.hcl files,
such as variables.pkr.hcl
variable "unused" {
type = string
default = null
}
file.chocolate: output will be in this color.
Build 'file.chocolate' finished after 762 microseconds.
==> Wait completed after 799 microseconds
==> Builds finished. The artifacts of successful builds are:
--> file.chocolate: Stored file: chocolate.txt
```
To be able to track HCP builds during a Packer build, we need to
propagate the name used for registering the build to HCP.
This works out-of-the-box for JSON templates, as the build's name is
always the builder's, so there's no confusion on that.
For HCP templates however, there's a possibility for a template to
define a name for the build, which is returned by a CoreBuild's Name()
function, in addition to the source's Type/Name.
The builds are registered to HCP with the source.String() function
however, which does not contain the build's name. This prevents any
build containing a name to work, as their name/source.String does not
match.
The name we registered the build with is stored in a CoreBuild as the
Type attribute, but cannot be safely accessed, as builds are types
within the command as packersdk.Build, which only exposes Name() for
this purpose.
In order to circumvent this problem, and as a way to present a prototype
of solution that will likely have to be discussed before we merge it,
this commit hotfixes the issue.
The initialization of packer core in JSON also validates that `null` variables were set, except in the case of `packer validate --syntax-only` , but after the refactor to allow to have all commands work with HCL2 and JSON this subtlety was lost.
This refactors the initialisation of the core in order to allow to have `packer validate --syntax-only` not error in case a variable is not set. Since these calls are refactored this works for HCL2 too.
fix#9478
* Update validate command to use FixConfig for checking against known
fixers
* Update validation command flag docs
* Add ConfigFixer method to PackerHandler Interface
* Implement ConfigFixer interface in PackerConfig
* Remove all stdout messaging (i.e calls to c.Ui.Say) in the validate
command. The command will only display hcl.Diagnotic messaging when there is an error or warning.
HCL2 Configs
```
⇶ packer validate docker_centos_shell_provisioner.pkr.hcl
```
JSON Configs
```
⇶ packer validate vmware-iso_ubuntu_minimal/vmware-iso_ubuntu_minimal.json
Error: Failed to prepare build: "vmware-iso"
1 error occurred:
* Deprecated configuration key: 'iso_checksum_type'. Please call `packer fix`
against your template to update your template to be compatable with the current
version of Packer. Visit https://www.packer.io/docs/commands/fix/ for more
detail.
Warning: Fixable configuration found.
You may need to run `packer fix` to get your build to run correctly.
See debug log for more information.
map[string]interface{}{
"builders": []interface{}{
map[string]interface{}{
... // 3 identical entries
"guest_os_type": string("ubuntu-64"),
"http_directory": string("http"),
- "iso_checksum":
string("946a6077af6f5f95a51f82fdc44051c7aa19f9cfc5f737954845a6050543d7c2"),
+ "iso_checksum":
string("sha256:946a6077af6f5f95a51f82fdc44051c7aa19f9cfc5f737954845a6050543d7c2"),
- "iso_checksum_type": string("sha256"),
"iso_url":
string("http://old-releases.ubuntu.com/releases/14.04.1/ubuntu-14.04.1-server-amd64.iso"),
"shutdown_command": string("echo 'vagrant' | sudo -S shutdown -P now"),
... // 4 identical entries
},
},
}
```
