04-one-webserver-with-vars

Terraform Web Server with vars example

This folder contains a web server with vars example of a Terraform file on Google Cloud Platform (GCP).

This Terraform file deploys a single web server on Google Cloud Platform (GCP). The web server returns "Hello, World" for the URL / listening on port 8080, which is defined as a variable.

Requirements

• You must have Terraform installed on your computer.
• You must have a Google Cloud Platform (GCP) account.
• You must have downloaded a Google Cloud Platform credentials file.
• You must have enabled the Google Compute Engine API.
• It uses the Terraform Google Cloud Provider that interacts with the many resources supported by Google Cloud Platform (GCP) through its APIs.
• This code was written for Terraform 0.10.x.

Using the code

• Configure your Google Cloud access keys.

  Two ways in order to configure credentials:

  • Configure GOOGLE_APPLICATION_CREDENTIALS environment variable. The variable must contain the path to the credentials file.

    To set these variable on Linux, macOS, or Unix, use export:

    export GOOGLE_APPLICATION_CREDENTIALS="~/.gcloud/terraform-examples-code.json"

    To set these variable on Windows, use set:

    set GOOGLE_APPLICATION_CREDENTIALS="C:\Users\USERNAME\.gcloud\terraform-examples-code.json"

  • Configure GOOGLE_CREDENTIALS environment variable. The variable must contain the content of the credentials file and not the path to it.

    To set these variable on Linux, macOS, or Unix, use export:

    export GOOGLE_CREDENTIALS="$(cat ~/.gcloud/terraform-examples-code.json)"

• Initialize working directory.

  The first command that should be run after writing a new Terraform configuration is the terraform init command in order to initialize a working directory containing Terraform configuration files. It is safe to run this command multiple times.

  terraform init

• Modify server port configuration.

  The web server is listening on port 8080, which is defined as an input variable server_port in vars.tf file.

  If you want to modify the server port you will be able to do it in several ways:

  • Loading variables from command line flags.

    Run Terraform commands in this way:

    terraform plan -var 'server_port=8080'

    terraform apply -var 'server_port=8080'

  • Loading variables from a file.

    When Terraform runs it will look for a file called terraform.tfvars. You can populate this file with variable values that will be loaded when Terraform runs. An example for the content of the terraform.tfvars file:

    server_port = "8080"

  • Loading variables from environment variables.

    Terraform will also parse any environment variables that are prefixed with TF_VAR. You can create an environment variable TF_VAR_server_port:

    TF_VAR_server_port=8080

  • Variable defaults.

    Change the value of the default attribute of server_port input variable in vars.tf file.

• Validate the changes.

  Run command:

  terraform plan

• Deploy the changes.

  Run command:

  terraform apply

• Test the web server.

  You can test it in two ways:

  • Running this command:

    curl http://<server_public_ip>:8080/

  • Writing in your browser this URL: http://<server_public_ip>:8080/

  You should get a Hello, World response message.

• Test the deploy.

  When the terraform apply command completes, use the Google Cloud console, you should see the new Google Compute instance.

• Clean up the resources created.

  When you have finished, run command:

  terraform destroy