resholve VS concise-encoding

I'm also not 100% on whether it answers the question, but I imagine you're thinking of https://github.com/abathur/resholve (doc in nixpkgs: https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/misc/resholve/README.md)

I intend to eventually find some time to figure out how feasible it would be to use https://github.com/abathur/resholve or wrapper techniques to bolt basalt (and perhaps other bash PMs) on to the nix ecosystem and nix-package some of your libraries.

(I'd love to have this ability for https://github.com/abathur/resholve to reliably identify arguments to one command that are also external commands/programs that it will in turn exec. I can't imagine trying to start it until/unless I have any bright ideas about how that executable spec and a parser for it would work.)

In https://github.com/abathur/resholve/blob/master/default.nix and https://github.com/abathur/resholve/blob/master/shell.nix you can see one approach to extending that line of thought to the default.nix itself.

Completions have in general been of interest, though the shell-specific completions I've looked at so far were all too dynamic.

I'd forgotten all about Fig since I saw your launch post here last year, so thanks for reminder. (I don't think I had quite started to work on parsing specific external commands, yet. Was still focused on just identifying the likely presence of exec in the executables.)

Are you familiar with the parse code? Are you handling painful stuff like combined short flags with a trailing option? (If I ferreted out some of the more painful cases I've had to wrangle, I am curious if you'd have a gut sense of whether your approach handles it. Would you mind if I reach out? I am working on this for https://github.com/abathur/resholve)

@dloreto @robrich A little aside from the announcement, but since it seems like you both work on this I wanted to surface something that came up down in a subthread:

I'm curious if you attempted to support macOS by doing this with Nix's dockerTools and cross-compiling (there may be better sources, but it's at least hinted at in https://nix.dev/tutorials/building-and-running-docker-images...)? If so, I'm wondering where that failed or bogged down?

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Background: I build a tool (https://github.com/abathur/resholve) for ~packaging Bash/Shell (i.e., for demanding all dependencies be present). The tool's technically agnostic, but I built it specifically to fix Shell packaging in Nix.

I think it could benefit a lot of other Shell projects, since one of Shell's big tribulations is dealing with heterogenous environments, but most Shell projects wouldn't see much reason to endure the pain of adopting Nix if they still had to support the heterogenous environments.

Much like you're doing here, I've entertained figuring out how to build a Nix-based packaging flow that can generate deployable standalone bundles or containers. It'd be a heavy way to bundle Shell, but I imagine some projects would take the tradeoff for predictability and reduced support load. But since it would need to take place within a Nix build, I'd need to cross-compile for it to work on macOS. Hoping you know if it's a dead-end or not :)

For a concrete example, I've been developing a tool (https://github.com/abathur/resholve) that can ~build/link Bash/Shell scripts--i.e., rewrite them with external executables converted to absolute paths. (This helps ensure dependencies are known, declared, present, and don't have to be on the global PATH for the script to execute cleanly.)

There's a devilish sub-problem, which is that any given executable can potentially exec arbitrary arguments. For now I handle this with a very crude automated binary/executable analysis that needs to be augmented by human source analysis. Deep multi-language source analysis wouldn't be very scalable, but I suspect fairly-standardized structural annotations could improve the results in a scalable way.

I have to imagine there are other applications of the same information.

I'm not 100% sure if you see the minimal PATH dependencies as a problem or not--so this may or may not help--but I develop https://github.com/abathur/resholve to make it easier to package Shell in Nix/nixpkgs by rewriting invocations of external dependencies in Shell scripts to absolute paths--and shunit2 is one of the Nix packages that I've updated to use resholve.

I came here to say this, too :)

But, of course, it still isn't a silver bullet...

1. You still have to have a sane PATH. A fair amount of the Nix install-related issues that get opened are PATH problems, and you can also run into problems with PATH in cron/launchd.

2. You still have to know what the script depends on. This can get tricky beyond small scripts you wrote yourself. (I write a tool for ~linking/resolving external dependencies in Shell scripts, https://github.com/abathur/resholve. As I've been working on converting some of nixpkgs' existing Shell packages to use it, I almost always find dependencies the initial packager missed.)

Check out resholve. https://github.com/abathur/resholve

"Local time" is time zone metadata. I've written a fair bit about timekeeping, because the context of what you're capturing becomes very important: https://github.com/kstenerud/concise-encoding/blob/master/ce...

This is basically why I ended up rolling my own text date format for Concise Encoding: https://github.com/kstenerud/concise-encoding/blob/master/ct...

ISO 8601 and RFC 3339 are fine for dates in the past, but they're not great as a general time format.

This looks similar to https://concise-encoding.org/

Dogma was developed as a consequence of trying to describe Concise Binary Encoding. The CBE spec used to look like the preserves binary spec, full of hex values, tables and various ad-hoc illustrations: https://preserves.dev/preserves-binary.html

Now the CBE formal description looks like this: https://github.com/kstenerud/concise-encoding/blob/master/cb...

And the regular documentation looks like this: https://github.com/kstenerud/concise-encoding/blob/master/cb...

Dogma also does text formats (Concise Encoding has a text and binary format, so I needed a metalanguage that could do both in order to make it less jarring for a reader):

https://github.com/kstenerud/concise-encoding/blob/master/ct...

https://github.com/kstenerud/concise-encoding/blob/master/ct...

Hey thanks for taking the time to critique!

I actually do have an ANTLR file that is about 90% of the way there ( https://github.com/kstenerud/concise-encoding/tree/master/an... ), so I could use those as a basis...

One thing I'm not sure about is how to define a BNF rule that says for example: "An identifier is a series of characters from unicode categories Cf, L, M, N, and these specific symbol characters". BNF feels very ASCII-centric...

It's still in the prerelease stage, but v1 will be released later this year. I'm mostly getting hits from China since they tend to be a lot more worried about security. I expect the rest of the world to catch on to the gaping security holes of JSON and friends in the next few years as the more sophisticated actors start taking advantage of them. For example https://github.com/kstenerud/concise-encoding/blob/master/ce...

There are still a few things to do:

- Update enctool (https://github.com/kstenerud/enctool) to integrate https://cuelang.org so that there's at least a command line schema validator for CE.

- Update the grammar file (https://github.com/kstenerud/concise-encoding/tree/master/an...) because it's a bit out of date.

- Revamp the compliance tests to be themselves written in Concise Encoding (for example https://github.com/kstenerud/go-concise-encoding/blob/master... but I'll be simplifying the format some more). That way, we can run the same tests on all CE implementations instead of everyone coming up with their own. I'll move the test definitions to their own repo when they're done and then you can just submodule it.

I'm thinking that they should look more like:

    c1

Ugh Unicode has been the bane of my existence trying to write a text format spec. I started by trying to forbid certain characters to keep files editable and avoid Unicode rendering exploits (like hiding text, or making structured text behave differently than it looks), but in the end it became so much like herding cats that I had to just settle on https://github.com/kstenerud/concise-encoding/blob/master/ct...

Basically allow everything except some separators, most control chars, and some lookalike characters (which have to be updated as more characters are added to Unicode). It's not as clean as I'd like, but it's at least manageable this way.

You might get a kick out of Concise Encoding then (shameless plug). It focuses on security and consistency of behavior.

https://concise-encoding.org/

In particular:

* How to deal with unrepresentable values: https://github.com/kstenerud/concise-encoding/blob/master/ce...

* Mandatory limits and security considerations: https://github.com/kstenerud/concise-encoding/blob/master/ce...

* Consistent error classification and processing: https://github.com/kstenerud/concise-encoding/blob/master/ce...

In the above example, `&a:` means mark the next object and give it symbolic identifier "a". `$a` means look up the reference to symbolic identifier "a". So this is a map whose "recusive link" key is a pointer to the map itself. How this data is represented internally by the receiver of such a document (a table, a struct, etc) is up to the implementation.

> - Time zones: ASN.1 supports ISO 8601 time types, including specification of local or UTC time.

Yes, this is the major failing of ISO 8601: They don't have true time zones. It only uses UTC offsets, which are a bad idea for so many reasons. https://github.com/kstenerud/concise-encoding/blob/master/ce...

> - Bin + txt: Again, I'm unclear on what you mean here, but ASN.1 has both binary and text-based encodings

Ah cool, didn't know about those.

> - Versioned: Also a little unclear to me

The intent is to specify the exact document formatting that the decoder can expect. For example we could in theory decide make CBE version 2 a bit-oriented format instead of byte-oriented in order to save space at the cost of processing time. It would be completely unreadable to a CBE 1 decoder, but since the document starts with 0x83 0x02 instead of 0x83 0x01, a CBE 1 decoder would say "I can't decode this" and a CBE 2 decoder would say "I can decode this".

With documents versioned to the spec, we can change even the fundamental structure of the format to deal with ANYTHING that might come up in future. Maybe a new security flaw in CBE 1 is discovered. Maybe a new data type becomes so popular that it would be crazy not to include it, etc. This avoids polluting the simpler encodings with deprecated types and bloating the format.