dhall-lang VS JHipster

Fail to see how this is any different than Dhall (https://dhall-lang.org/) other than it produces plists too.

Kubernetes config is a decent example. I had ChatGPT generate a representative silly example -- the content doesn't matter so much as the structure:

https://gist.github.com/cstrahan/528b00cd5c3a22e3d8f057bb1a7...

Now consider 100s (if not 1000s) of such files.

I haven't given Pkl an in depth look yet, but I can say that the Industry Standard™ of "simple YAML" + string substitution (with delicate, error prone indentation -- since YAML is indentation sensitive) is easily beat by any of:

- https://jsonnet.org/

- https://nickel-lang.org/

- https://nixos.org/manual/nix/stable/language/index.html

- https://dhall-lang.org/

- (insert many more here, probably including Pkl)

There are underpowered languages / tools, that can only solve a problem for which they are intended poorly. But not all limited tools are like that.

Say, eBPF is prominently not Turing-complete, which allows to guarantee that a eBPF program terminates, and even how soon. Still eBPF is hugely useful in its area.

Or, say, regular expressions are limited to regular languages; in particular, they famously [1] cannot process recursive structures, like trees. Still tools like grep / ag / rg are mightily useful.

Yes, I agree that YAML is underpowered for proper k8s configuration! But it's also too powerful for its own good in other aspects [2]. I wish Google used Dhall [3] or their own purely functional config language (FCL? I already forgot the name) instead of YAML; sadly, they did not.

[1]: https://stackoverflow.com/a/1732454/223424

[2]: https://ruudvanasseldonk.com/2023/01/11/the-yaml-document-fr...

[3]: https://dhall-lang.org/

Dhall: Dhall is a programmable configuration language that combines features like JSON, functions, types, and import capabilities. Its style leans towards functional programming, so if you're familiar with functional-style languages such as Haskell, you might find Dhall to be quite intuitive.

I've been thinking along these lines but more 'strongly validated' than statically typed in the sense that you'd be better off being able to load the entire config and then produce a list of problems (and should be able to offer good editor support if done correctly).

Though https://dhall-lang.org/ demonstrates that you can statically type quite a lot of configuration to great advantage, which appears to be programmatically embeddable in multiple languages per https://docs.dhall-lang.org/howtos/How-to-integrate-Dhall.ht...

> Where practical is in the sense of an engineer (or in their terms, a CS practitioner),

Configuration processing. E.g. I'd like my yamls to be decidable, though I'd settle for guaranteed to halt[1].

[1] https://dhall-lang.org/

Maybe you'd like jsonnet: https://jsonnet.org/

I find it particularly useful for configurations that often have repeated boilerplate, like ansible playbooks or deploying a bunch of "similar-but" services to kubernetes (with https://tanka.dev).

Dhall is also quite interesting, with some tradeoffs: https://dhall-lang.org/

A few years ago I did a small comparison by re-implementing one of my simpler ansible playbooks: https://github.com/retzkek/ansible-dhall-jsonnet

And to checkout Dhall: https://dhall-lang.org/

An easy way to get a pre-configured Keycloak instance is to use JHipster's jhipster-sample-app-oauth2 application. It gets updated with every JHipster release. You can clone it with the following command:

provider "auth0" { domain = "https://" debug = false } # Create a new Auth0 application for the JHipster app resource "auth0_client" "java_ms_client" { name = "JavaMicroservices" description = "Java Microservices Client Created Through Terraform" app_type = "regular_web" callbacks = ["http://localhost:8080/login/oauth2/code/oidc"] allowed_logout_urls = ["http://localhost:8080"] oidc_conformant = true jwt_configuration { alg = "RS256" } } # Configuring client_secret_post as an authentication method. resource "auth0_client_credentials" "java_ms_client_creds" { client_id = auth0_client.java_ms_client.id authentication_method = "client_secret_post" } # Create roles for the JHipster app resource "auth0_role" "admin" { name = "ROLE_ADMIN" description = "Administrator" } resource "auth0_role" "user" { name = "ROLE_USER" description = "User" } # Create an action to customize the authentication flow to add the roles and the username to the access token claims expected by JHipster applications. resource "auth0_action" "jhipster_action" { name = "jhipster_roles_claim" runtime = "node18" deploy = true code = <<-EOT /** * Handler that will be called during the execution of a PostLogin flow. * * @param {Event} event - Details about the user and the context in which they are logging in. * @param {PostLoginAPI} api - Interface whose methods can be used to change the behavior of the login. */ exports.onExecutePostLogin = async (event, api) => { const namespace = 'https://www.jhipster.tech'; if (event.authorization) { api.idToken.setCustomClaim(namespace + '/roles', event.authorization.roles); api.accessToken.setCustomClaim(namespace + '/roles', event.authorization.roles); } }; EOT supported_triggers { id = "post-login" version = "v3" } } # Attach the action to the login flow resource "auth0_trigger_actions" "login_flow" { trigger = "post-login" actions { id = auth0_action.jhipster_action.id display_name = auth0_action.jhipster_action.name } } # Create a test user. You can create more users here if needed resource "auth0_user" "test_user" { connection_name = "Username-Password-Authentication" name = "Jane Doe" email = "[email protected]" email_verified = true password = "passpass$12$12" # Don't set passwords like this in production! Use env variables instead. lifecycle { ignore_changes = [roles] } } resource "auth0_user_roles" "test_user_roles" { user_id = auth0_user.test_user.id roles = [auth0_role.admin.id, auth0_role.user.id] } output "auth0_webapp_client_id" { description = "Auth0 JavaMicroservices Client ID" value = auth0_client.java_ms_client.client_id } output "auth0_webapp_client_secret" { description = "Auth0 JavaMicroservices Client Secret" value = auth0_client_credentials.java_ms_client_creds.client_secret sensitive = true }

If you want a Spring backend with an Angular Frontend check out https://www.jhipster.tech. This is very nice for CRUD stuff.

Use https://www.jhipster.tech/

To test GitHub Actions, we need a new project which in this case I generated using JHipster with the configuration seen here:

exports.onExecutePostLogin = async (event, api) => { const namespace = 'https://www.jhipster.tech'; if (event.authorization) { api.idToken.setCustomClaim('preferred_username', event.user.email); api.idToken.setCustomClaim(`${namespace}/roles`, event.authorization.roles); api.accessToken.setCustomClaim(`${namespace}/roles`, event.authorization.roles); } }

What you maybe asking for is something like vaadin or jhipster which marries the front with the backend. (I don't like them tbh but it worth mentioning)

You can try this stack https://www.jhipster.tech with generator for mobile app https://github.com/jhipster/generator-jhipster-ionic.