troposphere-mate 0.0.1

Package short description.

---

Welcome to troposphere_mate Documentation

troposphere is a great Python library allow you to define AWS CloudFormation Resource in Python Class. But due to its implementation, IDLE can’t use attribute auto hint, and Type hint doesn’t work as well. troposphere_mate provides API exactly same as troposphere, but with availalbe Properties auto hint feature and type hint enabled. troposphere_mate is a thin wrapper layer on top of troposphere.

My goal is 100% API compatible to troposphere. Basically, you just need to replace from troposphere import Template, Ref, Tags, GetAtt to from troposphere_mate import Template, Ref, Tags, GetAtt.

Here’s how it looks like in IDLE:

How troposphere implements:

# content of troposphere.ec2.py
class Instance(AWSObject):
    resource_type = "AWS::EC2::Instance"

    props = {
        'InstanceType': (basestring, False),
        'SubnetId': (basestring, False),
        'KeyName': (basestring, False),
        ...
    }

How troposphere_mate implements:

@attr.s
class Instance(AWSObject):
    title = attr.ib() # type: str

    InstanceType = attr.ib(default=NOTHING) # type: str
    SubnetId = attr.ib(default=NOTHING) # type: str
    KeyName = attr.ib(default=NOTHING) # type: str

    template = attr.ib(default=None) # type: Template
    validation = attr.ib(default=True) # type: bool

    _aws_object_class = troposphere.ec2.Instance

Additional Features

Auto Reference

Sometimes, you just know you need to associate one AWS Resource to another, but you have to lookup the Document to find out which Property and what is the Syntax to do that.

For example, if you want to associate an IAM Role, VPC Subnet, Security Group to a Lambda Function.

Suppose you already have:

from troposphere_mate import ec2, awslambda, iam

tpl = Template()

iam_role = iam.Role(
    title="MyIamRole",
    template=tpl,
    RoleName="lambda-basic-execution",
    AssumeRolePolicyDocument={},
)

vpc = ec2.VPC(
    title="MyVPC",
    template=tpl,
    CidrBlock="10.53.0.0/16"
)

public_subnet1 = ec2.Subnet(
    title="PublicSubnet1",
    template=tpl,
    CidrBlock="10.53.0.0/16",
    VpcId=Ref(vpc)
)
public_subnet2 = ec2.Subnet(
    title="PublicSubnet2",
    template=tpl,
    CidrBlock="10.53.2.0/16",
    VpcId=Ref(vpc)
)

sg = ec2.SecurityGroup(
    title="LambdaSG",
    template=tpl,
    GroupDescription="Just a SG"
)

lbd_func = awslambda.Function(
    title="MyFunc",
    template=tpl,
    Code=awslambda.Code(
        S3Bucket="my-bucket",
        S3Key="0.0.1.zip",
    ),
    Handler="my_func.handler",
    Role="arn:aws:iam::111122223333:role/todo",
    Runtime="python3.6"
)

With troposphere_mate, you just need to do this:

from troposphere_mate import associate

associate(lbd_func, iam_role) # order doesn't matter, associate(iam_role, lbd_func)
associate(lbd_func, sg)
associate(lbd_func, public_subnet1)
associate(lbd_func, public_subnet2)

In other word, you don’t need to remember the properties and the syntax.

from troposphere import Ref
from troposphere import awslambda

lbd_func.Role = Ref(iam_role)
lbd_func.VpcConfig = awslambda.VPCConfig(
    SecurityGroupIds=[
        Ref(sg)
    ],
    SubnetIds=[
        Ref(public_subnet1),
        Ref(public_subnet2),
    ]
)

If you want to contribute your auto-associate logic to troposphere_mate, please submit issue or help me to improve. Here’s an example.

Install

troposphere_mate is released on PyPI, so all you need is:

$ pip install troposphere_mate

To upgrade to latest version:

$ pip install --upgrade troposphere_mate