This is not very readable:

Output.concat(
            "postgres://",
            root_user,
            ":",
            root_password.result,
            "@",
            cluster.endpoint,
            ":",
            cluster.port,
            "/{dbname}",
        )

(Ah, it’s also incorrect, I see a bug, but that’s besides the point.)

(Or maybe not. Maybe if I were using

interpolate

I wouldn’t have introduced that bug…)

Actually I’m having some trouble related to this expression! Looks like it’s related to

cluster.port

which is an

int

I think. When I run

pulumi up

I get this:

File "/usr/local/lib/python3.7/site-packages/pulumi/output.py", line 178, in run
        transformed: Input[U] = func(value)
    TypeError: sequence item 7: expected str instance, int found

Any chance you have a suggestion for fixing this?

(It’d be nice if

Output.concat

did this automatically)

Which makes sense to me, that that would happen.

Because

cluster.port

is an

Output

Or I guess it might be an

Input

with a default value…

don’t remember

(It’s an ECS cluster)

As long as we’re discussing the python experience, something else I’ve found a little annoying is that in some cases wherein something is typed as a string, and expects a stringified JSON value, I have to use

Output.all

to inject output values into the value that I’m going to stringify. Not everywhere, though; I’ve found that I can just pass a hash containing some Outputs inside it to the

policy

arg of the various AWS policy resources such as

UserPolicy

— which is great. But in another case, e.g. the

container_definitions

arg of an

ecs.TaskDefinition

, I can’t do that — it fails. I have to do something like this:

container_definitions=Output.all(repository.repository_url, db_url_secret.arn).apply(
            lambda vs: json.dumps(
                [
                    {
                        "name": base_name,
                        "image": vs[0],
etc…

that’s a lot of boilerplate and redirection that makes it hard to read and hard to work on.

This isn’t really a solution to your actual problem, but more like a perhaps more friendly way to use

Output.all

but you can use keyword args so you don’t have to refer to each value by its index. i.e.

container_definitions=Output.all(url=repository.repository_url, arn=db_url_secret.arn).apply(
            lambda vs: json.dumps(
                [
                    {
                        "name": base_name,
                        "image": vs["url"],
etc…

i dont get how it works, but my python is a little rusty

you might want to add an example like that to the docs

making it a little more realistic might help