133 lines
5.0 KiB
Plaintext
133 lines
5.0 KiB
Plaintext
---
|
|
page_title: Contextual Variables - HCL Configuration Language
|
|
sidebar_title: Contextual Variables
|
|
description: >-
|
|
Special variables provide connection information and basic instance state
|
|
information.
|
|
|
|
This page covers all existing special variables.
|
|
---
|
|
|
|
`@include 'from-1.5/beta-hcl2-note.mdx'`
|
|
|
|
`@include 'from-1.5/contextual-source-variables.mdx'`
|
|
|
|
# Build Variables
|
|
|
|
Build variables will allow you to access connection information and basic instance state information for a builder.
|
|
All special build variables are stored in the `build` variable:
|
|
|
|
```hcl
|
|
source "null" "first-example" {
|
|
communicator = "none"
|
|
}
|
|
|
|
build {
|
|
name = "my-build-name"
|
|
sources = ["null.first-example"]
|
|
|
|
provisioner "shell-local" {
|
|
environment_vars = ["TESTVAR=${build.PackerRunUUID}"]
|
|
inline = ["echo source.name is ${source.name}.",
|
|
"echo build.name is ${build.name}.",
|
|
"echo build.PackerRunUUID is $TESTVAR"]
|
|
}
|
|
}
|
|
```
|
|
|
|
Here is the list of available build variables:
|
|
|
|
- **name** Represents the name of the build block being run. This is different
|
|
than the name of the source block being run.
|
|
|
|
- **ID**: Represents the vm being provisioned. For example, in Amazon it is the instance id; in digitalocean,
|
|
it is the droplet id; in Vmware, it is the vm name.
|
|
|
|
- **Host**, **Port**, **User** and **Password**: The host, port, user, and password that Packer uses to access the machine.
|
|
Useful for using the shell local provisioner to run Ansible or Inspec against the provisioned instance.
|
|
|
|
- **ConnType**: Type of communicator being used. For example, for SSH communicator this will be "ssh".
|
|
|
|
- **PackerRunUUID**: Current build's unique id. Can be used to specify build artifacts.
|
|
An example of that, is when multiple builds runs at the same time producing the same artifact.
|
|
It's possible to differentiate these artifacts by naming them with the builds' unique ids.
|
|
|
|
- **PackerHTTPIP**, **PackerHTTPPort**, and **PackerHTTPAddr**: HTTP IP, port, and address of the file server Packer creates to serve items in the "http" dir to the vm. The HTTP address is displayed in the format `IP:PORT`.
|
|
|
|
- **SSHPublicKey** and **SSHPrivateKey**: The public and private key that Packer uses to connect to the instance.
|
|
These are unique to the SSH communicator and are unset when using other communicators.
|
|
**SSHPublicKey** and **SSHPrivateKey** can have escape sequences and special characters so their output should be single quoted to avoid surprises. For example:
|
|
|
|
```hcl
|
|
provisioner "shell" {
|
|
inline = ["echo '${build.SSHPrivateKey}' > /tmp/packer-session.pem"]
|
|
}
|
|
```
|
|
|
|
For backwards compatibility, `WinRMPassword` is also available through this
|
|
engine, though it is no different than using the more general `Password`.
|
|
|
|
All build variables are valid to use with any of the [HCL2 functions](/docs/templates/hcl_templates/functions).
|
|
Example of using [upper](/docs/templates/hcl_templates/functions/string/upper) to upper case the build ID:
|
|
|
|
```hcl
|
|
post-processor "shell-local" {
|
|
inline = ["echo ${upper(build.ID)}"]
|
|
}
|
|
```
|
|
|
|
For builder-specific builder variables, please also refer to the builder docs:
|
|
|
|
- Amazon EC2: [chroot](/docs/builders/amazon/chroot#build-shared-information-variables),
|
|
[EBS Volume](/docs/builders/amazon/ebsvolume#build-shared-information-variables),
|
|
[EBS](/docs/builders/amazon/ebs#build-shared-information-variables),
|
|
[EBS Surrogate](/docs/builders/amazon/ebssurrogate#build-shared-information-variables),
|
|
[Instance](/docs/builders/amazon/instance#build-shared-information-variables).
|
|
|
|
The HCL2 Special Build Variables is in beta; please report any issues or requests on the Packer
|
|
issue tracker on GitHub.
|
|
|
|
# Packer Version
|
|
|
|
This variable is set to the Packer version currently running.
|
|
|
|
```hcl
|
|
source "null" "first-example" {
|
|
communicator = "none"
|
|
}
|
|
|
|
build {
|
|
sources = ["null.first-example"]
|
|
|
|
provisioner "shell-local" {
|
|
inline = ["echo packer_version is '${packer.version}'"]
|
|
}
|
|
}
|
|
```
|
|
|
|
If you are running a development version of Packer, the version variable will
|
|
contain the released version number, dev flag, and current commit.
|
|
|
|
```shell-session
|
|
PACKER_LOG=0 packer build packer_version_demo.pkr.hcl
|
|
null.first-example: output will be in this color.
|
|
|
|
==> null.first-example: Running local shell script: /var/folders/8t/0yb5q0_x6mb2jldqq_vjn3lr0000gn/T/packer-shell083160352
|
|
null.first-example: packer_version is 1.6.5-dev (a69392129+CHANGES)
|
|
```
|
|
|
|
If you are running a released version of Packer, the version variable will
|
|
contain the released version number only:
|
|
|
|
```shell-session
|
|
PACKER_LOG=0 packer build packer_version_demo.pkr.hcl
|
|
null.first-example: output will be in this color.
|
|
|
|
==> null.first-example: Running local shell script: /var/folders/8t/0yb5q0_x6mb2jldqq_vjn3lr0000gn/T/packer-shell718995312
|
|
null.first-example: packer_version is 1.6.5
|
|
```
|
|
|
|
Make sure to wrap your variable in single quotes in order to escape the
|
|
string that is returned; if you are running a dev version of packer the
|
|
parenthesis may through off your shell escaping otherwise.
|