collect

This is a decorator used to create a collection. Collections are similar to Terraform modules except the resources are included in the root module rather than under a named module.

Decorated functions should:

• Accept a single argument var
• Yield pretf.api.tf blocks
  • Optionally including variable blocks to define inputs
  • Optionally including output blocks to define outputs

When using a collection, any required inputs defined by variable blocks must be passed in as keyword arguments. Any outputs defined by output blocks can be accessed as attributes of the collection.

Example:

from pretf.api import block
from pretf.collections import collect


def pretf_blocks():
    web = yield security_group(
        name="web",
        type="ingress",
        cidrs=["10.0.0.0/24", "192.168.0.0/24"],
        protocol="tcp",
        ports=[80, 443],
    )
    yield block("output", "web_sg_id", {"value": web.group.id})


@collect
def security_group(var):

    # Inputs.
    yield block("variable", "name", {})
    yield block("variable", "type", {})
    yield block("variable", "protocol", {})
    yield block("variable", "cidrs", {"default": []})
    yield block("variable", "ports", {"default": []})

    # Group resource.
    group = yield block("resource", "aws_security_group", var.name, {
        "name": var.name,
    })

    # Rule resources.
    for cidr in sorted(set(var.cidrs)):
        cidr_label = cidr.replace(".", "_").replace("/", "_")
        for port in var.ports:
            rule_label = f"{var.name}_{port}_from_{cidr_label}"
            yield block("resource", "aws_security_group_rule", rule_label,
                {
                    "security_group_id": group.id,
                    "type": "ingress",
                    "protocol": var.protocol,
                    "from_port": port,
                    "to_port": port,
                    "cidr_blocks": [cidr],
                },
            )

    # Outputs.
    yield block(f"output", "group", {"value": group})