Unknown Values: The Secret to Terraform Plan
log.martinatkins.me
log.martinatkins.me
That sure does sound like the author believes "pulumi preview" shouldn't ever work
Personally, I see the landscape like this: If you like CloudFormation templates, then Terraform is a better version of that. Especially as it’s workflows are very similar. If you like, or want, CDK then Pulumi will make you very happy, as it’s a much better version of that. Pulumi in particular makes some alternate patterns possible, e.g. using the integrated secret management, that give you more flexibility with how you approach your project.
As a side note, Pulumi is actively working with the community, accepting PRs, etc. and new provider APIs generally are available when they release. This may influence your decision, or not.
EDIT: Should mention that enabling bucket versioning here is also a little cherry on top (to me).
I haven't really looked under the hood but I strongly suspect I'm not that far away from truth. At some point I've seriously considered a question why I'm not just templating HCL directly rather than dealing with all those Pulumi oddities.
Either way it feels very different and pretty much alien.
Terraform's 0.12 release[0] was the shining light realization for me that Pulumi's was absolutely the better paradigm. When you start adding expressions, type systems, and ad-hoc iteration primitives to a DSL, you probably should be using a fully powered programming language.
As far as what is kind of offputting to you, I argue that of the two of them Pulumi is the only one with a shot of not doing it the write-it-out-to-text way. Building a representation of desired state is necessary to achieve the goals of both tools -- Pulumi gives you exposure to the objects that make up the tool in your programming language of choice, before they get serialized.
Another key innovation of Pulumi is that you can build those objects and abstractions much easier (IMO) than with TF (i.e. writing a provider), and you can build them with the tooling you're familiar with -- if you're using a supported pulumi language.
[0]: https://vadosware.io/post/setting-up-ses-with-pulumi/
[1]: https://www.hashicorp.com/blog/announcing-terraform-0-12
[0]: https://www.hashicorp.com/blog/announcing-terraform-0-12
The discussion part where you are not allowed (from Terraform lang) to create behavior dependent on the actual values of "Unknown" values (to prevent an ambiguous / non-deterministic plan), reminds of Applicatives vs Monads a bit.
(Sketchy potentially non-100% true illustration ahead)
For example, if you write a command-line parsing library using a Monad, then the set of command-line options is not an upfront fixed set easy to list with --help, but can change depending on previous command line options (here the command line parsing can peek into the upfront "Unknown" values, the options used and their values, to generate even more options).
While if you write it using Applicative, then peeking into the actual values is not possible, you can't create branching behaviour.
EDIT: and note that Pulumi has language targets in C#, Typescript, golang, and Python
there is absolutely no reason why you shouldn't be able to express your definition in python, or ruby or json.
anyone remember Vagrant? Where you could write your config is a Ruby DSL and could drop into Ruby whenever you wanted to do something "special"?