Generating Files Dynamically with FMPP

AIOP allows for the dynamic generation of files during the build phase. This can be useful for generating configuration files, data files, and specific code files based on your declarations.

The principle is to create a template with predefined tags as well as custom tags that will be replaced by values defined in the resource declaration. AIOP relies on the tool FMPP to generate the files dynamically. It is also possible to use Jinja.

Conditions

To use this feature, you need to install the fmpp dependency on your machine (see installation).

Usage

FMPP is simple to use. Let's look at some ways to use it. Here is a guide to help you get started:

1. Create an FMPP Template

An FMPP template is essentially a text file with special tags that will be replaced by dynamic values. For example, suppose you have a template.txt file with the following content:

template.txt

Hello ${name},

Thank you for your order of ${product}. Your order will be shipped to the following address:
${address}.

Best regards,
The Sales Team

2. Declare the Template

Next, declare the template in your playbook as follows:

- source: template.txt
  destination: file.txt
  template: fmpp
  compatibility:
    - system:
      template_data:
        name: My Name
        product: My Product
        address: My Address

The result after package generation:

file.txt

Hello My Name,

Thank you for your order of My Product. Your order will be shipped to the following address:
My Address.

Best regards,
The Sales Team

3. Use Control Structures

Jinja allows you to use control structures such as loops and conditions to generate more complex dynamic content. For example:

template.txt

Hello ${name},

Thank you for your order of ${product}. Your order contains the following items:

<#list articles as article>
  - ${a}
</#list>

Your order will be shipped to the following address:
${address}.

Best regards,
The Sales Team

4. Declare the Template

And in the declaration:

- source: template.txt
  destination: file.txt
  template: jinja
  compatibility:
    - system:
      template_data:
        name: My Name
        product: My Product
        articles: [Article1, Article2]
        address: My Address

The result after package generation:

file.txt

Hello My Name,

Thank you for your order of My Product. Your order contains the following items:

- Article1
- Article2

Your order will be shipped to the following address:
My Address.

Best regards,
The Sales Team

Go Further

FMPP is a very powerful template engine and offers advanced features that we will not discuss here. To learn more, consult the official documentation (opens in a new tab). For a list of predefined functions by FMPP, see this documentation (opens in a new tab).

Learn more about declaring a template: Declare a template.

Finally, AIOP predefines variables for templates, the list of which can be found here.

Pre-defined variables Jinja