Dotted packages pass build in WASM but don't work

[willhausman]

Short description

Using this sample, https://github.com/open-policy-agent/npm-opa-wasm/tree/main/examples/nodejs-app, with OPA 0.35 installed on my machine.

I changed the package from example to example.dotted, and could no longer retrieve a result from evaluation.

Steps To Reproduce

package example.dotted

default hello = false

hello {
    x := input.message
    x == data.world
}

I ran these commands for compiling and running the wasm:

opa build -t wasm -e 'example.dotted' ./example.rego
tar -xzf ./bundle.tar.gz /policy.wasm
node app.js '{"message": "world"}' 

The output is an empty array. [].

Expected behavior

I expect dotted package names to work in wasms the same as a server, or at least some documentation saying it isn't supported.
https://play.openpolicyagent.org/p/3gdkg5nd8q

Additional context

I found my way to this use case because I was making a wasm to run in C# with Wasmtime and wanted to provide a builtin to call some C# code. I never got a result out of the wasm, and noticed that my call to the exported builtins wasm function did not return any mapped functions for me to connect with. I eventually removed the dot from my package name simply because I was desperate to match samples as closely as possible, and then my builtins started showing up.

[srenatus]

Excuse my brevity, but please try example/dotted as entrypoint. That's the format and we should probably call that out somewhere better.

[willhausman]

Excuse my brevity, but please try example/dotted as entrypoint. That's the format and we should probably call that out somewhere better.

Ahh, that makes sense for how paths happen from a REST endpoint as well. Thanks!

[srenatus]

Your issue is further evidence that #3957 is a thing we should do.

[anderseknert]

This has bitten me too in the past, even if not in the context of Wasm. Failing on non-existing paths would be good, but I wonder if we can't just accept both forms whenever a path like this is expected. Postel's Law and all that :) Meaning that if there is an example/dotted path/entrypoint (or path in the SDK, or whatever). These would all be accepted (possibly with a info/debug message about the preferred form):

example/dotted
example.dotted
data.example.dotted

[srenatus]

That's a good idea. We'll only need to figure out what to do when there's both

package foo.example.dotted

and

package foo["example.dotted"]

[anderseknert]

You mean both of those packages would exist inside of the same OPA? I'd honestly be fine with keeping the current behavor for that edge case... it's like they'd want problems, so let them have them 😆

[stale]

This issue has been automatically marked as inactive because it has not had any activity in the last 30 days.

[ashutosh-narkar]

Should we update the docs and the opa build instructions with the entrypoint format to close out this issue ? cc @srenatus

[srenatus]

@ashutosh-narkar Yeah. I would prefer @anderseknert's "let's just do the right thing when we can figure out what it is" approach, but documentation is the low-hanging fruit here.

[stale]

This issue has been automatically marked as inactive because it has not had any activity in the last 30 days.

[srenatus]

#3957