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HashiTalks 2025

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Stop breaking things

and start testing!

Terraform Test Framework - Hallway Track Follow-Up!

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HashiCorp Ambassador

LinkedIn: jeremy-j-myers

Jeremy

Myers

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Table of Contents/�Agenda

Terraform Testing Framework Intro & Basics

Terraform Testing Framework State

Terraform Testing “At-Scale” in Pipelines

Terraform Test Mocking

Review / Wrap-Up

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Terraform Testing Framework

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Terraform Testing Framework Intro

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HCL based configuration language to test Terraform Modules.

Integration Testing

Locally
CI/CD

Terraform CLI v1.6.0 or later
Module Validation

Variable Verification
Provider Verification
Capability Verification

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Terraform Testing Framework Folder Structure

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NEW folder for tests

sub folders for setup or pre and post activities (optional)
*.tftest.hcl files for each test
*.tftest.json

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Terraform Testing Framework File Layout

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One to Many RUN blocks

One to Many PROVIDER blocks - ALIAS are allowed

Plan or Apply COMMAND

VARIABLE block - global / plan specific

override module defaults

None to Many ASSERT blocks

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Terraform testing beyond the basics

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TEST 1 - PLAN -

TEST 2 - PLAN

TEST 3 - APPLY

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Demo Time

Less Talk - More Code!

storage-account

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TF Test Apply Strategy - All About the State

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module. setup_rg

state

create_sa_stnd &

create_sa_change_tag

state

update in place

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Congratulations

Testing Framework Associate Badge

Note: It’s not a real thing!

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Terraform Testing Beyond Basics

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Module Lifecycle

Initial Release

Basic deployment with required parameters.

Add Functionality / Capabilities

Enable complex configurations

Provider Upgrade

Breaking Changes

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Test ALL Versions

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Testing Multi-Version Modules

Tag Based vs Branch Based

HCP Terraform Cloud

HCP Modules - BRANCH based
MUST enable testing capability via HCP Portal when module is published
Can test lastest version of module.
Tests run when new commits are made to MAIN branch.

Can be triggered via terraform cli
terraform test -cloud-run=app.terraform.io/hashiconf24/storage-account/azurerm

CI/CD via Pipelines

HCP Modules - version TAG based
Leverage terraform cli test commands
Can test 1 to Many versions of HCP registry module by referencing TAG’s
Set to Test on CRON schedule

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Multi-Version

Module Testing

virtual machines

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Mocking Time

Let’s all pretend for a minute!

virtual machines

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Mocking

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Load Balancer Terraform Module

Terraform will NOT build the resource, but return data about the resource AS-IF it had created the resource.

Very useful for resources that require extended deployment time.

Virtual Machines
Databases
Kubernetes
Machine Learning

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Quick Re-Cap

https://events.hashicorp.com/hashitalks2025

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Types of Terraform Tests

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Produces in Memory State files
Will NOT catch ALL provider API errors
Variable Validation - Positive / Negative
Fast
Test EVERYTHING & EVERY SCENARIO

Produces in Memory State files
Provider API Validation
Long Running - Resource Dependent
Mocking - Reduces Run time
Test High Priority Scenarios

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How about you?

What big lesson have you learned?

Share your knowledge in the chat!

Pro Tips / Recommendations

Test File Naming & Strategy

Executes Alphabetically!
Use numbers to order.
Use RANDOM everywhere!
How many tests per file?

Combine the plans
Separate the applys

Mocking

Returns VALID resource data
Fake it… so you don’t have to make it!
Cuts APPLY test times down

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Additional Learning

Mattias Fjellstrom - fellow Ambassador

A Comprehensive Guide to Testing in Terraform

YouTube - Highly Recommend!

Terraform Test Mocking - Learn with GVR

CI/CD Pipelines Examples

AzDO - CI/CD Terraform Tests

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hugs@hashicorp.com | learn.hashicorp.com | discuss.hashicorp.com

Thank you

LinkedIn: jeremy-j-myers

Jeremy

Myers

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hello@hashicorp.com

Thank you

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Thank you

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Thank you