I’ve been looking around for a scripting language that:
- has a cli interpreter
- is a “general purpose” language (yes, awk is touring complete but no way I’m using that except for manipulating text)
- allows to write in a functional style (ie. it has functions like map, fold, etc and allows to pass functions around as arguments)
- has a small disk footprint
- has decent documentation (doesn’t need to be great: I can figure out most things, but I don’t want to have to look at the interpter source code to do so)
- has a simple/straightforward setup (ideally, it should be a single executable that I can just copy to a remote system, use to run a script and then delete)
Do you know of something that would fit the bill?
Here’s a use case (the one I run into today, but this is a recurring thing for me).
For my homelab I need (well, want) to generate a luhn mod n check digit (it’s for my provisioning scripts to generate synchting device ids from their certificates).
I couldn’t find ready-made utilities for this and I might actually need might a variation of the “official” algorithm (IIUC syncthing had a bug in their initial implementation and decided to run with it).
I don’t have python (or even bash) available in all my systems, and so my goto language for script is usually sh (yes, posix sh), which in all honestly is quite frustrating for manipulating data.
Why aren’t python and bash be available in all your systems? Which languages would be?
I would’ve recommended python, otherwise perl or Haskell (maybe Haskell’s too big) or something, but now I’m worried that whatever reason makes python undoable also makes perl etc. undoable
Mate, I came on here to post Haskell as a semi-ironic ‘joke’ and it’s included in the top comment. You’ve made my day.
I mean, it’s a functional programming language and an incredibly good one. But it probably has a far too big footprint for their use-case…
Oh, I know. I adore Haskell.
Why aren’t python and bash be available in all your systems?
Among others, I run stuff on alpine and openwrt.
I don’t need to run these scripts everywhere (strictly speaking, I don’t need the homlab at all), but I was wondering if there’s something that I can adopt as a default goto solution without having to worry about how each system is packaged/configured.
As for python, I doubt the full version would fit in my router plus as said I don’t want to deal with libraries/virtualenvs/… and (in the future) with which distro comes with python3 vs pyton4 (2 vs 3 was enough). Openwrt does have smaller python packages, but then I would be using different implementations on different systems: again something I’d rather not deal with.
As for perl, it would be small enough, but I find it a bit archaic/esoteric (prejudice, I know), plus again I don’t want to deal with how every distro decides to package the different things (eg. openwrt has some 40+ packages for perl - if I were doing serious development that would be ok, but I don’t want to worry about that for just some scripts).
Sounds like you want MicroPython. It’s definitely available on OpenWrt and AlpineLinux and has a very small footprint.
If you don’t like Python, have a look at Lua/luajit.
You’ve defined yourself into an impossible bind: you want something extremely portable, universal but with a small disk imprint, and you want it to be general purpose and versatile.
The problem is that to be universal and general purpose, you need a lot of libraries to interact with whatever type of systems you might have it on (and the peculiarities of each), and you need libraries that do whatever type of interactions with those systems that you specify.
E.g. under-the-hood, python’s
open("<filename>", 'r')
is a systemcall to the kernel. But is that Linux? BSD? Windows NT? Android? Mach?What if you want your script to run a CLI command in a subshell? Should it call “cmd”? or “sh”? or “powershell”? Okay, okay, now all you need it to do is show the contents of a file… But is the command “cat” or “type” or “Get-FileContents”?
Or maybe you want to do more than simple read/write to files and string operations. Want to have graphics? That’s a library. Want serialization for data? That’s a library. Want to read from spreadsheets? That’s a library. Want to parse XML? That’s a library.
So you’re looking at a single binary that’s several GBs in size, either as a standalone or a self-extracting installer.
Okay, maybe you’ll only ever need a small subset of libraries (basic arithmetic, string manipulation, and file ops, all on standard glibc gnu systems ofc), so it’s not really “general purpose” anymore. So you find one that’s small, but it doesn’t completely fit your use case (for example, it can’t parse uci config files); you find another that does what you need it to, but also way too much and has a huge footprint; you find that perfect medium and it has a small, niche userbase… so the documentation is meager and it’s not easy to learn.
At this point you realize that any language that’s both easy to learn and powerful enough to manage all instances of some vague notion of “computer” will necessarily evolve to being general purpose. And being general purpose requires dependencies. And dependencies reduce portability.
At this point your options are: make your own language and interpreter that does exactly what you want and nothing more (so all the dependencies can be compiled in), or decide which criteria you are willing to compromise on.
Is compiling scripts an option? Aka compiling them in C, C++, Rust, whatever for your router on another machine, and copying and executing those binaries on your router?
You might be interested in Raku. It is Perl6, or what used to be called Perl6, but it deviated too far away from the original perl and it ended up with a different team of developers than perl 5, so they forked it, changed the name and turned it into a new language.
if there’s something that I can adopt as a default goto solution without having to worry about how each system is packaged/configured.
Go is probably your best bet. Simple to use, and you can compile it so it runs everywhere
I found installing Go-sdk a total PiTA. It is okay as a developer environment. But bash + gnu utils + core utils seem much more sane to me.
Of course I mostly work with Linux systems and hardly ever have to deal with Scripting for Windoze.
luajit
is small, fast(well, it can jit), and has a small but complete standard library and can do FFI pretty easily, should be ideal for most homelab usecaseldd $(which luajit) linux-vdso.so.1 (0x00007ffee9dc7000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fb4db618000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fb4db613000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007fb4db5f3000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fb4db3ca000) /lib64/ld-linux-x86-64.so.2 (0x00007fb4db799000)
Python is what you want. You can install it on just about any system.
Other than that maybe Lua but that will be hell.
Python is what you want. You can install it on just about any system.
Perl and bash are already there, no need to install anything.
Perl isn’t normally preinstalled by Python is. (On Linux)
Try it now - go on. Type “perl” and tell me what you get.
And if you’re so certain it’s not used, try removing it and see how well your computer works afterwards.
Welp, can’t argue with that
If you just run perl it will sit waiting for input. Try perl --version
It isn’t installed
I know that because I installed it as it was a dependency of Buildroot.
Edit: My bad I must of been thinking about a Perl library
Once git no longer depends on it, it’ll be gone from my system
Is this the case? I don’t feel like I’ve ever had to install Perl but I’ve had to install Python plenty of times and I use both pretty frequently on a daily basis. Not to mention a newer version, older version, 2.7.4 instead of 2.7.3.
Python 2 is no longer supported and shouldn’t be used.
Um, exactly the opposite on all the distros I use. All Enterprise Linux distros, Suse and Debian.
What about Lua/Luajit?
In most scripting languages you have the interpreter binary and the (standard) libraries as separate files. But creating self-extracting executables, that clean up after themselves can easily be done by wrapping them in a shell script.
IMO, if low dependencies and small size is really important, you could also just write your script in a low level compiled language (C, Rust, Zig, …), link it statically (e.g. with musl) and execute that.
I use Lua for this sort of thing. Not my favorite language, but it works well for it. Easy to build for any system in the last 20-30 years, and probably the next 20 too. The executable is small so you can just redistribute it or stick it in version control.
Micropython.
That does seem to be just one, maybe two small files, and no dependencies. And a built in map() function.
Perl is already installed on most linux machines and unless you start delving into module usage, you won’t need to install anything else.
Python is more fashionable, but needs installing on the host and environments can get complicated. I don’t think it scales as well as Perl, if that’s a concern of yours.
I can’t really think of anything that’s less frustrating than sh and ticks all your boxes. You can try TCL but it’s bound to be a shit show. It was painful to use two decades ago.
Perl is a step up in terms of developer comfort, but it’s at the same time too big and too awkward to use.
Maybe a statically linked Python?
I was thinking about recommending TCL as a joke. My favorite thing about it is it’s “whimsicly typed.”
Perl is a step up in terms of developer comfort, but it’s at the same time too big and too awkward to use.
How do you mean?
It’s already on nearly every distro, so there’s no core size unless you lean into modules. The scripts aren’t exactly big either.
He doesn’t have bash. I’m not sure I’ve seen a system this millennium with Perl but not bash.
Try it now - type perl. It’s a dependency on a huge amount of core system tools.
OP is on OpenWRT (a router distro), and Alpine. Those distros don’t come with very much by default, and perl is not a core dependency for any of their default tools. Neither is python.
Based on the way the cosmo project has statically linked builds of python, but not perl, I’m guessing it’s more difficult to create a statically linked perl. This means that it’s more difficult to put perl on a system where it isn’t already there, and that system doesn’t have a package manager*, than python or other options.
*or the the user doesn’t want to use a package manager. OP said they just want to copy a binary around. Can you do that with perl?
OP is on OpenWRT
Fair point - I missed that, buried in the comments as it was.
In that scenario, you use what’s available, I guess.
OP said they just want to copy a binary around. Can you do that with perl?
This is linux. Someone will have done it.
I don’t have python (or even bash) available in all my systems, and so my goto language for script is usually sh (yes, posix sh), which in all honestly is quite frustrating for manipulating data.
Why are you making it hard on yourself? apt/dnf install a language to use and use it.
I honestly love Powershell, but haven’t tried the Linux version yet. I only use Bash on linux but it has a load of odd quirks that make it unpleasant to use imo. Can’t comment on anything else.
Pwsh 7.x works very well in Linux. Haven’t got any snags.
I use powershell for work as I need the m365 modules for work and its very flexible with decent module availability to plug in all sorts.
However it absolutely sucks for large data handling, anything over 10k rows is just horrendous, I typically work with a few million rows. You can make it work with using .Net to process it within your script but its something to be aware of. Being able to extend with .Net can be extremely useful.
Realistically whatever problems you see in python will be there for any other language. Python is the most ubiquitously available thing after bash for a reason.
Also you mentioned provisioning scripts, is that Ansible? If so python is already there, if you mean really just bash scripts I can tell you that does not scale well. Also if you already have some scriptsz what language are they on? Why not write the function there?
Also you’re running syncthing on these machines, I don’t think python is larger than that (but I might be wrong).
Also you mentioned provisioning scripts, is that Ansible? If so python is already there, if you mean really just bash scripts I can tell you that does not scale well. Also if you already have some scriptsz what language are they on? Why not write the function there??
Currently it’s mostly nixos, plus a custom thing that generates preconfigured openwrt images that I then deploy manually. I have a mess of other vms and stuff, but I plan to phase out everything and migrate to nixos (except the openwrt stuff, since nixos doesn’t run on mips).
I don’t really need to run this specific synchthing-ID script except on my PC (I do the provisioning from there), but I have written scripts that run on my router (using busybox sh) and I was wondering if there is a “goto” scripting that I can use everywhere.
another vote for Lua – lua5.4 is available for all 8 Alpine architectures, tiny installed size (120–200 kB) (and Alpine package only installs two files)
Only 5 years ago, everybody would be singing and shouting “perl”.
Nowadays it is python that has taken this position (even though Perl is still there and can do so much more).
More like
20 years ago - perl
10 years ago - python
Nowadays - go
Go isn’t a scripting language
Go isn’t a scripting language, and it isn’t a system language either, despite what Wikipedia currently says. To be a system language, a language should support assembly language and shouldn’t require an embedded garbage collector. And if you’re going to make a compiled language anyway, why not make it capable of system work? Go is a platypus that’s popular with devops for some reason—probably Google’s clout in the industry.
The one thing Go does have going for is performance. It compiles and runs pretty fast. It isn’t as fast as C but it is very close.
And it has a pretty excellent stdlib.
Perl is a pain to work with
Python is a lot less pain
Even after using CPAN ? I found Perl to be much more “manageable” than Python.
Python with Venv and Pip at least works as expected. Which makes it easier.
Python has a clean syntax and is popular. I can’t say the same for Perl. Also I’m not sure if Perl is cross platform.
Why would you say that Perl “can do so much more” than Python? That assertion sounds indefensible.
LOL It is one of the most well known things about perl that the language is as mighty as probably no other programming language.
Right, so you’ve got nothing to back it up. Sure, 1990s, let’s get you back to bed.
The smallest footprint for an actual scripting probably will be posix sh - since you already have it ready.
A slightly bigger footprint would be Python or Lua.
If you can drop your requirement for actual scripting and are willing to add a compile step, Go and it’s ecosystem is pretty dang powerful and it’s really easy to learn for small automation tasks.
Personally, with the requirement of not adding too much space for runtimes, I’d write it in go. You don’t need a runtime, you can compile it to a really small zero dependency lib and you have clean and readable code that you can extend, test and maintain easily.
No one has mentioned PHP yet? Man, times really have changed.
I used it for scripting a decade after everyone else, but even I have to admit PHP is rarely the best choice now.
For data processing?
Yeah, it’s really flexible when it comes to arrays and string processing. Super easy to work with, too.
I’ve actually tried using PHP on OpenWRT and embedded before. It’s not exactly lightweight, it’s a memory and CPU hog. Keep in mind that the kind of machine that runs OpenWRT might only have 32 or even 16 MB of RAM to work with.
Also, PHP is not the first language that comes to mind when doing data processing and/or functional programming. You can but it doesn’t lend itself well to it.
I still love bash. I’m able to accomplish quite a lot with it. I vote bash.
Also vote bash, but I don’t love it…more of a tolerate.
Bash? On windows it’s pretty much unusable even if you use cygwin. Python or Lua are the only reasonable suggestions here
I just assumed the scripts would run on Linux.
Nah, gross. You need to set a bunch of global options to get sane behavior on errors.
Nushell is shaping up really really nicely, and it’ll actually stop executing if something fails! Even if that happens in a pipe! And it’s not super eager to convert between arrays and strings if you use the wrong cryptic rune.