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Comment by chopraaa | Hacker News Reader

If you feel YAML is too complicated for you, a host of problems await for anything you want to do in infrastructure...

Ansible has it's own set of features that are largely abstracted out by it's YAML playbook syntax. You can run it across any (or almost) system, from Linux to Windows and even networking devices. You can create modules in any language you want.

For speeding up Ansible runs, a number of optimisations can be made including using Mitogen https://mitogen.networkgenomics.com/ansible_detailed.html

Alternatives listed in the blog post don't even come close to the speed and power of Ansible.

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> If you feel YAML is too complicated for you, a host of problems await for anything you want to do in infrastructure...

This is an uncharitable dismissal of a valid point. Think a bit more about the concern: is it that YAML is too hard or that it’s adding complexity in addition to that inherent to the work? You’re taking the domain-specific challenges of whatever you’re doing and adding YAML’s quirks like magic type conversion, various syntax oddities which just have to be memorized, requirement for a domain specific linter to validate things like macros, etc.; the various Ansible conventions for variable declaration and manipulation, programming language-like loops and conditionals, mix of raw Python and Jinja2 template syntax; the whole complex system for doing inventory and host/group variables; the various modules’ different implementation decisions for how they accept arguments and what they return; and the fact that those modules are wrapping other libraries which you can’t call directly (AWS adds something, wait for boto3 to add it, wait for Ansible to add it, find out that they forgot to add the optional feature you need, repeat). YAML is part of the concern and it especially adds wrinkles like needing dialect-specific editor / formatter / linter support to get the formatting and validation support which using a programming language would give out of the box but most of it comes back to using a document formatting language to write what inevitably needs to be code.

The counter-argument is that it’s easier to start with and that the high-level module interface avoids needing to write as much code. I think that’s a valid goal but it makes me wish there was an easier way to drop code into a project than writing a plugin: imagine if you hit a tricky place with the basic modules but could just drop a .py task in and have the richness of full Python with type validation telling you that an argument is incorrect before your deploy fails 10 minutes in.

> Ansible has its own set of features that are largely abstracted out by its YAML playbook syntax.

I don't understand what YAML has to do with abstraction. The example from pyinfra is pretty much the same as the ansible equivalent. Whether the feature set is comparable is a different question (I agree with you, it's probably nowhere close to ansible).

    apt.packages(
        {'Install iftop'},
        'iftop',
        sudo=True,
        update=True,
    )

> If you feel YAML is too complicated for you

Ansible YAML is a poor substitute for a real language once you add conditional logic to the mix. Another huge downside is that composition in YAML is much harder than in any programming language. A Python (or dhall, or cue) library that compiled to ansible would be pretty swell.

Ansible YAML is a poor substitute for a real language once you add conditional logic to the mix. Another huge downside is that composition in YAML is much harder than in any programming language

Given that the average devops person is already stuck with yaml, many of those problems are addressed by jsonnet. But I agree, having it in the language would be preferable. I think it stems from the desire to make infrastructure declarative, which isn't really the case when your declarations are dynamic.

I've written a lot of Ansible in the past year. While I'm happy with the work, I'd admit to looking at some of the logic I've had to put together with clunky, esoteric constructs like `with_nested_items` and the super colloquial variable system, while thinking "it's great to be able to do this stuff, but htf am I going to explain this code to a newbie?".

I'd like some kind of 'sensible', backwards compatible layer in Ansible that would allow me to rewrite stuff in raw Python, with 'normal' code, where it makes sense, but keep YAML for constructs that do actually look and work like lists of basic tasks.

Stuff that gets too complex you can pretty easily abstract into a role and jump into Python.

https://opendev.org/zuul/zuul-jobs/src/branch/master/roles/t... is a nice example of some pretty complex co-install of libraries for testing under tox (and you can unit test bits of it too...).

https://zuul-ci.org/docs/zuul-jobs/ is a collection of roles and playbooks that do a lot of complicated things with nice abstractions such as this. Although they're designed to be called from the Zuul CI system, there's many good examples for anyone wanting to build out their Ansible in a scalable and maintainable way.

> I don't understand what YAML has to do with abstraction. The example from pyinfra is pretty much the same as the ansible equivalent.

I said this in continuation to the line you quoted:

> You can run it across any (or almost) system, from Linux to Windows and even networking devices. You can create modules in any language you want.

This is abstracted in YAML so that anyone who uses any modules does not need to know the language it is written in. Only the YAML syntax.

> This is abstracted in YAML so that anyone who uses any modules does not need to know the language it is written in. Only the YAML syntax.

And the declarative and imperative language you've built on top of that.

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