Terraform - Revision history

Christoph: /* Introduction */

2022-07-19T23:51:39Z

‎Introduction

Christoph: /* Hello, World */

2022-05-05T23:24:37Z

‎Hello, World

Christoph: /* Examples */

2022-05-05T21:27:53Z

‎Examples

Christoph: /* See also */

2022-04-22T21:08:02Z

‎See also

Christoph: /* See also */

2022-04-15T00:49:52Z

‎See also

Christoph: /* Basic example #1 */

2021-10-19T07:19:02Z

‎Basic example #1

Christoph: /* Basic example #2 */

2021-10-19T07:18:38Z

‎Basic example #2

Christoph: /* See also */

2021-10-19T07:14:52Z

‎See also

Christoph: /* See also */

2021-07-08T00:42:12Z

‎See also

Christoph: /* External links */

2021-07-08T00:05:27Z

‎External links

← Older revision		Revision as of 23:51, 19 July 2022
Line 11:		Line 11:

	A high-level difference and/or reason to use Terraform over CAPS (Chef, [[Ansible]], Puppet, Salt) is that these others have a focus on automating the installation and configuration of software (i.e., keeping the machines in compliance and in a certain state). Terraform, however, can automate the provisioning of the infrastructure itself (e.g., in [[:Category:AWS\|AWS]] or [[Google Cloud Platform\|GCP]]). One can, of course, do the same with, say, Ansible. However, Terraform really shines in infrastructure management and automation.		A high-level difference and/or reason to use Terraform over CAPS (Chef, [[Ansible]], Puppet, Salt) is that these others have a focus on automating the installation and configuration of software (i.e., keeping the machines in compliance and in a certain state). Terraform, however, can automate the provisioning of the infrastructure itself (e.g., in [[:Category:AWS\|AWS]] or [[Google Cloud Platform\|GCP]]). One can, of course, do the same with, say, Ansible. However, Terraform really shines in infrastructure management and automation.
		+
		+	==Terraform cheatsheet==
		+
		+	; General commands
		+
		+	* Get Terraform version:
		+	$ terraform version
		+
		+	* Download and update root modules:
		+	$ terraform get -update=true
		+
		+	* Open up a Terraform interactive command:
		+	$ terraform console
		+
		+	* Create a DOT diagram of Terraform dependencies:
		+	$ terraform graph \| dot -Tpng > graph.png
		+
		+	* Format Terraform code to HCL standards:
		+	$ terraform fmt
		+
		+	* Validate Terraform code syntax:
		+	$ terraform validate
		+
		+	* Enable tab auto-completion in the terminal
		+	$ terraform -install-autocomplete
		+
		+	* Show information about provider requirements:
		+	$ terraform providers
		+
		+	* Login and logout of Terraform Cloud:
		+	$ terraform login
		+	$ terraform logout
		+
		+	; Workspaces
		+
		+	* List the available workspaces
		+	$ terraform workspace list
		+
		+	* Create a new workspace:
		+	$ terraform workspace new development
		+
		+	* Select an existing workspace:
		+	$ terraform workspace select default
		+
		+	; Initialize Terraform
		+
		+	* Initialize Terraform in the current working directory:
		+	$ terraform init
		+
		+	* Skip plugin installation:
		+	$ terraform init -get-plugins=false
		+
		+	* Force plugin installation from a directory:
		+	$ terraform init -plugin-dir=PATH
		+
		+	* Upgrade modules and plugins at initialization:
		+	$ terraform init -upgrade
		+
		+	* Update backend configuration:
		+	$ terraform init -migrate-state -force-copy
		+
		+	* Skip backend configuration:
		+	$ terraform init -backend=false
		+
		+	* Use a local backend configuration:
		+	$ terraform init -backend-config=FILE
		+
		+	* Change state lock timeout (default is zero seconds):
		+	$ terraform init -lock-timeout=120s
		+
		+	; Plan Terraform
		+
		+	* Produce a plan with difference between code and state:
		+	$ terraform plan
		+
		+	* Output a plan file for reference during apply:
		+	$ terraform plan -out current.tfplan
		+
		+	* Output a plan to show effect of Terraform destroy:
		+	$ terraform plan -destroy
		+
		+	* Target a specific resource for deploying:
		+	$ terraform plan -target=ADDRESS
		+
		+	Note that the <code>-target</code> option is also available for the <code>terraform apply</code> and <code>terraform destroy</code> commands.
		+
		+	; Outputs
		+
		+	* List available outputs:
		+	$ terraform output
		+
		+	* Output a specific value:
		+	$ terraform output NAME
		+
		+	; Apply Terraform
		+
		+	* Apply the current statue of Terraform code:
		+	$ terraform apply
		+
		+	* Specify a previously generated plan to apply:
		+	$ terraform apply current.tfplan
		+
		+	* Enable auto-approval or automation:
		+	$ terraform apply -auto-approve
		+
		+	; Destroy Terraform
		+
		+	* Destroy resources managed by Terraform state:
		+	$ terraform destroy
		+
		+	* Enable auto-approval or automation:
		+	$ terraform destroy -auto-approve
		+
		+	; Manage Terraform State
		+
		+	* List all resources in Terraform state:
		+	$ terraform state list
		+
		+	* Show details about a specific resource:
		+	$ terraform state show ADDRESS
		+
		+	* Track an existing resource in state under a new name:
		+	$ terraform state mv SOURCE DESTINATION
		+
		+	* Import a manually-created resource into state:
		+	$ terraform state import ADDRESS ID
		+
		+	* Pull state and save to a local file:
		+	$ terraform state pull > terraform.tfstate
		+
		+	* Push state to a remote location:
		+	$ terraform state push PATH
		+
		+	* Replace a resource provider:
		+	$ terraform state replace-provider A B
		+
		+	* Taint a resource to force redeployment on apply:
		+	$ terraform taint ADDRESS
		+
		+	* Untaint a previously tainted resource:
		+	$ terraform untaint ADDRESS

	==Examples==		==Examples==

@@ Line 21: / Line 21: @@
 <pre>
 terraform {
    # This module is now only being tested with Terraform 0.13.x. However, to make upgrading easier, we are setting
@@ Line 32: / Line 33: @@
    value = "Hello, Redapt!"
+}
 </pre>

← Older revision		Revision as of 21:27, 5 May 2022
Line 13:		Line 13:

	==Examples==		==Examples==
		+
		+	===Hello, World===
		+
		+	This section contains the simplest possible Terraform module—one that just outputs "Hello, World"—to demonstrate how you can use Terratest to write automated tests for your Terraform code.
		+
		+	Note that this module does not do anything useful; it is just here to demonstrate the simplest usage pattern for Terratest. For a slightly more complicated example of a Terraform module and the corresponding tests, see [https://github.com/gruntwork-io/terratest/tree/master/examples/terraform-basic-example terraform-basic-example].
		+
		+	<pre>
		+	terraform {
		+	# This module is now only being tested with Terraform 0.13.x. However, to make upgrading easier, we are setting
		+	# 0.12.26 as the minimum version, as that version added support for required_providers with source URLs, making it
		+	# forwards compatible with 0.13.x code.
		+	required_version = ">= 0.12.26"
		+	}
		+
		+	# website::tag::1:: The simplest possible Terraform module: it just outputs "Hello, World!"
		+	output "hello_world" {
		+	value = "Hello, Redapt!"
		+	}
		+	</pre>
		+
	===Basic example #1===		===Basic example #1===

@@ Line 2,117: / Line 2,117: @@
 * [https://github.com/instrumenta/conftest conftest]
 * [https://github.com/gruntwork-io/terratest terratest]
 ==External links==

@@ Line 2,109: / Line 2,109: @@
 * [[Ansible]]
 * [[Pulumi]]
 * [https://github.com/terraform-linters/ tfline]
 * [https://github.com/wayfair/terrafirma terrafirma]

@@ Line 22: / Line 22: @@
 * Create a Terraform file describing the AWS EC2 instance to create:
 <pre>
-$ cat << EOF >> instance.tf
+$ cat << EOF > instance.tf
 provider "aws" {
    access_key = "<REDACTED>"

@@ Line 87: / Line 87: @@
 The contents of each of the above files should look like the following:
 <pre>
-$ cat << EOF >> instance.tf
+$ cat << EOF > instance.tf
 resource "aws_instance" "example" {
    ami           = "${lookup(var.AMIS, var.AWS_REGION)}"
@@ Line 94: / Line 94: @@
 EOF
-$ cat << EOF >> provider.tf
+$ cat << EOF > provider.tf
 provider "aws" {
    access_key = "${var.AWS_ACCESS_KEY}"
@@ Line 102: / Line 102: @@
 EOF
-$ cat << EOF >> terraform.tfvars
+$ cat << EOF > terraform.tfvars
 AWS_ACCESS_KEY = "<REDACTED>"
 AWS_SECRET_KEY = "<REDACTED>"
 EOF
-$ cat << EOF >> vars.tf
+$ cat << EOF > vars.tf
 variable "AWS_ACCESS_KEY" {}
 variable "AWS_SECRET_KEY" {}