how do I implement if condition in my cloudformation stack - json

Question

I have two attributes in my stack enviornment and iamprofileName. If I select one of the non-prod enviornment i.e "use1dev","use1qa". I should get MyPlatformEC2NonProd as default value in "IAMProfileName"
If I select one of the prod enviornments i.e "useProd1","useProd2".I must get MyPlatformEC2Prod as default value in "IAMProfileName"
How can I achieve this
"Environment" : {
"Description" : "Environment being deployed to - use1dev, use1qa,
use1sbox etc",
"Type" : "String",
"Default" : "use1sbox",
"AllowedValues" : ["use1dev","use1qa","useProd1","useProd2"]
},
"IAMProfileName" : {
"Default" : "MyPlatformEC2",
"Type" : "String",
"Description" : "Name of IAM profile to attach to created
machines",
"AllowedValues" : ["MyPlatformEC2","MyPlatformEC2NonProd"]

Answer 1

Use CloudFormation conditions. For example in your case, I would do something like the following:
Conditions:
"ProdProfileCondition": {
"Fn::Or": [
{"Fn::Equals": ["useProd1", {"Ref": "Environment"}]},
{"Fn::Equals": ["useProd2", {"Ref": "Environment"}]},
]
}
Now wherever you want to use the IAMProfileName value, use something like the following,
SomeAWSResource:
Properties:
"ProfileName" : [{
"Fn::If" : [
"ProdProfileCondition",
{"Ref" : "MyPlatformEC2"},
{"Ref" : "MyPlatformEC2NonProd"}
]
}]
For more information on how to use conditionals, check out the following link.
Also, you can achieve more complicated conditionals using Jinja, just create a template and fill values according to conditions. But I wouldn't go into details of that because what you need can be fulfilled by this already.
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference-conditions.html