Import Variable Plugin

Fetch output values from another environment and insert them as terraform variables.

Overview

This plugin will fetch output values from another environment and insert them as terraform and/or environment variables.

Similar to self hosted agent secrets, use this notation in the value of the terraform input value:

  • ${env0:<environment id>:<output name>}
  • ${env0:<environment name>:<output name>} (see note below about Environment Names restrictions)
  • ${env0-workflow:<parent node name>:<output name>}

For fetching output values that contain lists (like subnet ids) or maps (like tags), make sure you select JSON type for your input variable, and in the value use the following JSON schema.

  • {"ENV0_ENVIRONMENT_NAME":<environment name>, "output": <output name>}
  • {"ENV0_WORKFLOW_PARENT":<parent name>, "output": <output name>}

For more information, check out the Import Variable Plugin git repository.

Requirements

To use this plugin, you need to setup the env0 API key and secret for the environment. You can use an Organization API Key or a Personal API Key.

  1. ENV0_API_KEY (Required)
  2. ENV0_API_SECRET (Required)

Usage

Add the following env0.yaml custom flow file to your environment or project.

version: 2  
deploy:  
  steps:  
    terraformPlan:  
      before:  
        - name: Import Variables
          use: https://github.com/env0/[email protected]
  1. Configure the Custom Flow above with a new environment or an existing environment
  2. Add a Terraform Variable
  3. The Key is the name of your Terraform variable
  4. The Value is a reference to another environment's output variable. With the following format: ${env0:<env0_environment_id>:<output_key>}
  5. Run the environment, and env0 will fetch the value

Workflows

When using the plugin within a workflow you can use the following notation:

string types: ${env0-workflow:<parent name>:<output name>}
json types: {"ENV0_WORKFLOW_PARENT":<parent name>, "output": <output name>}

In this case, the parent name is the yaml parent, not the "environment name."
For example, given the following env0.workflow.yaml the variable structure to fetch the "vpc-id" from the "parent vpc" would be ${env0-workflow:vpc:vpc-id} Similarly, to fetch the tags (in json) from the vpc: {"ENV0_WORKFLOW_PARENT":vpc, "output": tags}

environments:  
  vpc:  
    name: 'My VPC'  
    templateName: 'vpc-template'  
  subnet:  
    name: 'My Subnets'  
    templateName: 'subnet-template'  
    needs:  
      - vpc

Environment Name Restrictions

  • Environment Names must be unique, otherwise, the script just uses the "first" matching environment name.
  • Environment Names must not include spaces " " or slashes /. Ideally, your environment only contains alphanumeric characters and dashes -. **

Inputs

N/A

Example Usage

In this example we will run fetch the variable from a "Dev VPC" environment.

version: 2
deploy:
  steps:
    terraformPlan:  
      before:
        - name: Import Variables # The name that will be presented in the UI for this step
          use: https://github.com/env0/[email protected]
          inputs: {}

  1. Configure the Custom Flow above with a new environment or an existing environment
  2. Add a Terraform Variable
  3. The Key is the name of your Terraform variable
  4. The Value is a reference to another environment's output variable. For example, if I needed the VPC ID from my "Dev VPC" Environment:
  • First I need to get the ENV0_ENVIRONMENT_ID from that environment.
    note: the Environment ID can be found in the URL: https://app.env0.com/p/7320dd7a-4822-426c-84b5-62ddd8be0799/environments/9cec1eb6-c17f-4cca-9cdf-606a23cdf6b5 where 9cec1eb6-c17f-4cca-9cdf-606a23cdf6b5 is the ENV0_ENVIRONMENT_ID.
  • Find the output name in the environment Resources tab. e.g. vpc_id
  • The value you enter would be then: ${env0:9cec1eb6-c17f-4cca-9cdf-606a23cdf6b5:vpc_id}
  1. Run the environment, and env0 will fetch the value

Further Reading

This plugin takes advantage of Terraform variable precendence and *.auto.tfvars.

** If you must know why, it's because this script is written in Bash, and I'm taking advantage of Bash arrays which doesn't process spaces well, and also I'm saving the outputs to the filesystem which gets confused with slashes.