158 lines
4.2 KiB
Plaintext
158 lines
4.2 KiB
Plaintext
---
|
|
description: |
|
|
The `packer console` command allows you to experiment with Packer variable
|
|
interpolations.
|
|
page_title: packer console - Commands
|
|
sidebar_title: <tt>console</tt>
|
|
---
|
|
|
|
# `console` Command
|
|
|
|
The `packer console` command allows you to experiment with Packer variable
|
|
interpolations. You may access variables in the Packer config you called the
|
|
console with, or provide variables when you call console using the -var or
|
|
-var-file command line options.
|
|
|
|
~> **Note:** `console` is available from version 1.4.2 and above.
|
|
|
|
~> **Note:** For HCL2 `console` is available from version 1.6.0 and above, use
|
|
`packer console --config-type=hcl2` to try it without a config file. Go
|
|
templating ( or `{{..}}` calls ) will not work in HCL2 mode.
|
|
|
|
Type in the interpolation to test and hit `<enter>` to see the result.
|
|
|
|
To exit the console, type "exit" and hit `<enter>`, or use Control-C.
|
|
|
|
```shell-session
|
|
$ packer console my_template.json
|
|
```
|
|
|
|
The full list of options that the console command will accept is visible in the
|
|
help output, which can be seen via `packer console -h`.
|
|
|
|
## Options
|
|
|
|
- `-var` - Set a variable in your packer template. This option can be used
|
|
multiple times. This is useful for setting version numbers for your build.
|
|
example: `-var "myvar=asdf"`
|
|
|
|
- `-var-file` - Set template variables from a file.
|
|
example: `-var-file myvars.json`
|
|
|
|
## REPL commands
|
|
|
|
- `help` - displays help text for Packer console.
|
|
|
|
- `exit` - exits the console
|
|
|
|
- `variables` - prints a list of all variables read into the console from the
|
|
`-var` option, `-var-files` option, and template.
|
|
|
|
## Usage Examples - repl session ( JSON )
|
|
|
|
Let's say you launch a console using a Packer template `example_template.json`:
|
|
|
|
```shell-session
|
|
$ packer console example_template.json
|
|
```
|
|
|
|
You'll be dropped into a prompt that allows you to enter template functions and
|
|
see how they're evaluated; for example, if the variable `myvar` is defined in
|
|
your example_template's variable section:
|
|
|
|
```json
|
|
"variables":{
|
|
"myvar": "asdfasdf"
|
|
},
|
|
...
|
|
```
|
|
|
|
and you enter `` {{user `myvar`}} `` in the Packer console, you'll see the value of
|
|
myvar:
|
|
|
|
```shell-session
|
|
> {{user `myvar`}}
|
|
asdfasdf
|
|
```
|
|
|
|
From there you can test more complicated interpolations:
|
|
|
|
```shell-session
|
|
> {{user `myvar`}}-{{timestamp}}
|
|
asdfasdf-1559854396
|
|
```
|
|
|
|
And when you're done using the console, just type "exit" or CTRL-C
|
|
|
|
```shell-session
|
|
> exit
|
|
$
|
|
```
|
|
|
|
If you'd like to provide a variable or variable files, you'd do this:
|
|
|
|
```shell-session
|
|
$ packer console -var "myvar=fdsafdsa" -var-file myvars.json example_template.json
|
|
```
|
|
|
|
If you don't have specific variables or var files you want to test, and just
|
|
want to experiment with a particular template engine, you can do so by simply
|
|
calling `packer console` without a template file.
|
|
|
|
## Usage Examples - piped commands ( JSON )
|
|
|
|
If you'd like to just see a specific single interpolation without launching
|
|
the REPL, you can do so by echoing and piping the string into the console
|
|
command:
|
|
|
|
```shell-session
|
|
$ echo {{timestamp}} | packer console
|
|
1559855090
|
|
```
|
|
|
|
## Usage Examples - repl session ( HCL2 )
|
|
|
|
~> **Note:** For HCL2 `console` is available from version 1.6.0 and above, use
|
|
`packer console --config-type=hcl2` to try it without a config file. Go
|
|
templating ( or `{{..}}` calls ) will not work in HCL2 mode.
|
|
|
|
Without a config file, `packer console` can be used to experiment with the
|
|
expression syntax and [built-in functions](/docs/from-1.5/functions).
|
|
|
|
### Starting
|
|
|
|
To start a session on a folder containing HCL2 config files, run:
|
|
|
|
```shell-session
|
|
packer console folder/
|
|
```
|
|
|
|
Because `folder/` is a folder Packer will start in HCL2 mode, you can also
|
|
directly pass an HCL2 formatted config file:
|
|
|
|
```shell-session
|
|
packer console file.pkr.hcl
|
|
```
|
|
|
|
Because the file is suffixed with `.pkr.hcl` Packer will start in HCL2 mode.
|
|
|
|
When you just want to play arround without a config file you can set the
|
|
`--config-type=hcl2` option and Packer will start in HCL2 mode:
|
|
|
|
```shell-session
|
|
packer console --config-type=hcl2
|
|
```
|
|
|
|
### Scripting
|
|
|
|
The `packer console` command can be used in non-interactive scripts by piping
|
|
newline-separated commands to it. Only the output from the final command is
|
|
printed unless an error occurs earlier.
|
|
|
|
For example:
|
|
|
|
```shell-session
|
|
$ echo "1 + 5" | packer console
|
|
6
|
|
```
|