Value Interpolation

Introduction

Oftentimes, you will need to define variables whose values depend on other variables. To do this, you can use Value interpolation.

Examples

• An environment variable identifier containing a complete identifier for your Bunnyshell environment.

{{ project.name }} : {{ org.name }} : {{ env.name }}

• A variable that is using the identifier variable to create a logging content prefix.

{{ "now"|date("m/d/Y") }} {{ env.var.identifier|lower }}

• A variable that interpolates a conditional value

{% if env.type == 'ephemeral' %}true{% else %}false{% endif %}

Where to use value interpolation

• Variables (at Project, Environment, or Application level)

• Components / docker-compose:

  • Build arguments

  • Build context

  • Build Dockerfile

  • Build target

• Helm Charts

  • Values

• Terraform

  • Input variables

  • Configuration variables

  • Environment variables

• Static applications build command

Available interpolation values

• Organization variables

  • org.name

  • org.unique

• Project variables

  • project.name

• Environment variables

  • env.unique

  • env.name

  • env.type - primary / ephemeral

  • env.k8s.namespace

  • env.vars.NAME

• Components variables

  • components.COMPONENT_NAME.image

  • components.COMPONENT_NAME.gitBranch

  • components.COMPONENT_NAME.ingress.hosts[*]

  • components.COMPONENT_NAME.vars.NAME

  • components.COMPONENT_NAME.exported.NAME - exported variables from the Generic Components deploy steps

  The "COMPONENT_NAME" should have the value of your target component name, with all the non-alphanumerical characters replaced with underscore (_).

• Terraform

  • tf.MODULE_NAME.input.NAME

  • tf.MODULE_NAME.output.NAME - complex values can be accessed further (ie. tf.MODULE_NAME.output.endpoints.api[0].port)

Available methods that can be used with the values interpolation

The interpolation mechanism uses Twig for rendering the values. So the syntax needs to be a valid Twig syntax.

The available Twig filters are:

• lower

• capitalize, date

• date_modify

• default

• json_encode

• length

• replace

• slice

• slug

• title

• trim

• upper

• url_encode.

The available Twig functions are:

• random

• date

• max

• min.