Is there any workaround to use if statement in troposphere templates?

Question

I'm trying to add an if statement in add_resource of troposphere, but I can't. Is there any workaround to do so?

s3_bucket = t.add_resource(Bucket(
    "MyBucket",
    if 2>1:
       BucketName="bucket1",
    else:
       BucketName="bucket2",
    CorsConfiguration=CorsConfiguration(
        "CorsConfiguration",
        CorsRules=[CorsRules(
            "AllowOrganization",
            AllowedMethods=["GET"],
            AllowedOrigins=["*"],
        )]
    ),
    Tags=Tags(
        Environment="aa",
    )
))

Edit:

I tried to use ternary operators as well, but it didn't work.

BucketName= if 2 > 1: "bucket2" else: "bucket3",

@mkrieger1 unfortunately not. I'm basically trying to do this inside of add_resource function parameters. I get this "if" is not definedPylancereportUndefinedVariable https://github.com/cloudtools/troposphere/blob/master/troposphere/s3.py#L475 — cosmos-1905-14, Jun 25 '21 at 14:49
That's because you didn't use it correctly. `BucketName="bucket1" if 2>1 else "bucket2"` would be the correct syntax. — mkrieger1, Jun 25 '21 at 16:08

Florian Fasmeyer · Accepted Answer · 2021-06-25T20:31:16.070

2

if you want to control the parameters, then you can do your if-statement before the function.

if 2 > 1:
    BucketName="bucket1"
else:
    BucketName="bucket2"

s3_bucket = t.add_resource(Bucket(
        "MyBucket",
        BucketName,
        ...
    ))

Or you can use ternary operators:

s3_bucket = t.add_resource(Bucket(
        "MyBucket",
        "bucket1" if 2 > 1 else "bucket2",
        ...
    ))

Note: 2 > 1 will always be true. But I guess you will replace 2 with a variable?

edited Jun 25 '21 at 20:31

answered Jun 25 '21 at 14:33

Florian Fasmeyer

795
5
18

it didnt work. I get this "if" is not definedPylancereportUndefinedVariable – cosmos-1905-14 Jun 25 '21 at 14:42
Remove your code (past it in a temp txt). Run print('hello world'). If it works, just make a simple if-statement and print: if True: Print('hello world'). – Florian Fasmeyer Jun 25 '21 at 14:46
What is a Pylancereport? I don't think the bucket is a Pylancereport. You may have an issue with your settings – Florian Fasmeyer Jun 25 '21 at 14:49
I think this is because of me trying to run if statement inside of add.resource function of parameters. Do you know troposphere? https://github.com/cloudtools/troposphere/blob/master/troposphere/s3.py#L475 – cosmos-1905-14 Jun 25 '21 at 15:17
You didn't write the ternary operator right: A if [condition] else B, you did if[condition] A else B. ;) – Florian Fasmeyer Jun 25 '21 at 15:28
you're great! Thanks for catching it! – cosmos-1905-14 Jun 25 '21 at 19:01

Is there any workaround to use if statement in troposphere templates?

1 Answers1