I was working on creating EC2 images using Packer. For that, there’s the amazon-ebs Packer Builder to use.
After checking that there’s nothing wrong with the syntax, thanks to packer validate --syntax-only /path/to/packter-template.pkr.hcr, I ran packer validate /path/to/packter-template.pkr.hcr and got the error below:
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packer validate --syntax-only /path/to/packter-template.pkr.hcr
Syntax-only check passed. Everything looks okay.
packer validate /path/to/packter-template.pkr.hcr
Error: 2 error(s) occurred:
* A source_ami or source_ami_filter must be specified
* For security reasons, your source AMI filter must declare an owner.
on/path/to/packter-template.pkr.hcr line 42:
(source code not available)
The question became
is
source_amiset ? If so, why isn’t packer finding it?
The source_ami is set but expects a value from an environment variable.
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. . .
variable "source_ami" {
type = string
default = env("SOURCE_AMI")
}
. . .
source "amazon-ebs" "ami_name" {
. . .
source_ami = var.source_ami
}
Because packer uses the env function, the next step is to set SOURCE_AMI as an environment variable.
In the CI part with AWS CodeBuild, SOURCE_AMI is set by Cloudformation. To validate packer locally means that I need to set SOURCE_AMI to some value.
Setting SOURCE_AMI as a “normal” variable, even after taking into account the precedence of how packer evaluates variables, doesn’t work. E.g., using the -var option when ivoking packer: packer validate -var SOURCE_AMI=1234 Packer/template.pkr.hcl
In my Powershell console, I set the environment variable with $env:SOURCE_AMI = '1234' and invoke packer validate --syntax-only /path/to/packter-template.pkr.hcr