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This may make some people pull their hair out, but I’d love to hear some arguments. I’ve had the impression that people really don’t like bash, not from here, but just from people I’ve worked with.

There was a task at work where we wanted something that’ll run on a regular basis, and doesn’t do anything complex aside from reading from the database and sending the output to some web API. Pretty common these days.

I can’t think of a simpler scripting language to use than bash. Here are my reasons:

  • Reading from the environment is easy, and so is falling back to some value; just do ${VAR:-fallback}; no need to write another if-statement to check for nullity. Wanna check if a variable’s set to something expected? if [[ <test goes here> ]]; then <handle>; fi
  • Reading from arguments is also straightforward; instead of a import os; os.args[1] in Python, you just do $1.
  • Sending a file via HTTP as part of an application/x-www-form-urlencoded request is super easy with curl. In most programming languages, you’d have to manually open the file, read them into bytes, before putting it into your request for the http library that you need to import. curl already does all that.
  • Need to read from a curl response and it’s JSON? Reach for jq.
  • Instead of having to set up a connection object/instance to your database, give sqlite, psql, duckdb or whichever cli db client a connection string with your query and be on your way.
  • Shipping is… fairly easy? Especially if docker is common in your infrastructure. Pull Ubuntu or debian or alpine, install your dependencies through the package manager, and you’re good to go. If you stay within Linux and don’t have to deal with differences in bash and core utilities between different OSes (looking at you macOS), and assuming you tried to not to do anything too crazy and bring in necessary dependencies in the form of calling them, it should be fairly portable.

Sure, there can be security vulnerability concerns, but you’d still have to deal with the same problems with your Pythons your Rubies etc.

For most bash gotchas, shellcheck does a great job at warning you about them, and telling how to address those gotchas.

There are probably a bunch of other considerations but I can’t think of them off the top of my head, but I’ve addressed a bunch before.

So what’s the dealeo? What am I missing that may not actually be addressable?

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"Use the best tool for the job, that the person doing the job is best at." That's my approach.

I will use bash or python dart or whatever the project uses.

[-] MITM0@lemmy.world 3 points 3 days ago

Well then you guys will love what this guy (by tha name "icitry") did with bash https://www.youtube.com/watch?v=b_WGoPaNPMY

He created a youtube clone with Bash

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[-] MonkderVierte@lemmy.ml 2 points 3 days ago* (last edited 3 days ago)

Run checkbashisms over your $PATH (grep for #!/bin/sh). That's the problem with Bash.
#!/bin/sh is for POSIX compliant shell scripts only, use #!/bin/bash if you use bash syntax.

Btw, i quite like yash.

[-] FooBarrington@lemmy.world 1 points 3 days ago

Any reason to use #!/bin/sh over #!/usr/bin/env sh?

[-] MonkderVierte@lemmy.ml 1 points 3 days ago* (last edited 3 days ago)

I personally don't see the point in using the absolute path to a tool to look up the relative path of your shell, because shell is always /bin/sh but the env binary might not even exist.

Maybe use it with bash, some BSD's or whatever might have it in /usr without having /bin symlinked to /usr/bin.

[-] Badland9085@lemm.ee 1 points 3 days ago

There are times when doing so does make sense, eg if you need the script to be portable. Of course, it’s the least of your worries in that scenario. Not all systems have bash being accessible at /bin like you said, and some would much prefer that you use the first bash that appears in their PATH, e.g. in nix.

But yeah, it’s generally pretty safe to assume /bin/sh will give you a shell. But there are, apparently, distributions that symlink that to bash, and I’ve even heard of it being symlinked to dash.

[-] MonkderVierte@lemmy.ml 1 points 3 days ago* (last edited 3 days ago)

Not all systems have bash being accessible at /bin like you say

Yeah, but my point is, neither match they /usr/bin/env. Bash, ok; but POSIX shell and Python, just leave it away.

and I’ve even heard of it being symlinked to dash.

I think Debian and Ubuntu do that (or one of them). And me too on Artix, there's dash-as-bin-sh in AUR, a pacman hook that symlinks. Nothing important breaks by doing so.

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[-] toynbee@lemmy.world 3 points 3 days ago

Over the last ten - fifteen years, I've written lots of scripts for production in bash. They've all served their purposes (after thorough testing) and not failed. Pretty sure one of my oldest (and biggest) is called temporary_fixes.sh and is still in use today. Another one (admittedly not in production) was partially responsible for getting me my current job, I guess because the interviewers wanted to see what kind of person would solve a coding challenge in bash.

However, I would generally agree that - while bash is good for many things and perhaps even "good enough" - any moderately complex problem is probably better solved using a different language.

[-] syklemil@discuss.tchncs.de 4 points 4 days ago

At the level you're describing it's fine. Preferably use shellcheck and set -euo pipefail to make it more normal.

But once I have any of:

  • nested control structures, or
  • multiple functions, or
  • have to think about handling anything else than simple strings that other programs manipulate (including thinking about bash arrays or IFS), or
  • bash scoping,
  • producing my own formatted logs at different log levels,

I'm on to Python or something else. It's better to get off bash before you have to juggle complexity in it.

[-] vext01@lemmy.sdf.org 2 points 3 days ago

-e is great until there's a command that you want to allow to fail in some scenario.

I know OP is talking about bash specifically but pipefail isn't portable and I'm not always on a system with bash installed.

[-] syklemil@discuss.tchncs.de 1 points 3 days ago

-e is great until there’s a command that you want to allow to fail in some scenario.

Yeah, I sometimes do

set +e
do_stuff
set -e

It's sort of the bash equivalent of a

try { 
  do_stuff()
} 
catch { 
  /* intentionally bare catch for any exception and error */
  /* usually a noop, but you could try some stuff with if and $? */ 
}

I know OP is talking about bash specifically but pipefail isn’t portable and I’m not always on a system with bash installed.

Yeah, I'm happy I don't really have to deal with that. My worst-case is having to ship to some developer machines running macos which has bash from the stone ages, but I can still do stuff like rely on [[ rather than have to deal with [ . I don't have a particular fondness for using bash as anything but a sort of config file (with export SETTING1=... etc) and some light handling of other applications, but I have even less fondness for POSIX sh. At that point I'm liable to rewrite it in Python, or if that's not availaible in a user-friendly manner either, build a small static binary.

[-] vext01@lemmy.sdf.org 2 points 3 days ago

It's nice to agree with someone on the Internet for once :)

Have a great day!

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[-] morbidcactus@lemmy.ca 1 points 3 days ago

I'm fine with bash for ci/cd activities, for what you're talking about I'd maybe use bash to control/schedule running of a script in something like python to query and push to an api but I do totally get using the tools you have available.

I use bash a lot for automation but PowerShell is really nice for tasks like this and has been available in linux for a while. Seen it deployed into production for more or less this task, grabbing data from a sql server table and passing to SharePoint. It's more powerful than a shell language probably needs to be, but it's legitimately one of the nicer products MS has done.

End of the day, use the right tool for the job at hand and be aware of risks. You can totally make web requests from sql server using ole automation procedures, set up a trigger to fire on update and send data to an api from a stored proc, if I recall there's a reason they're disabled by default (it's been a very long time) but you can do it.

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[-] friend_of_satan@lemmy.world 2 points 3 days ago
[-] Ephera@lemmy.ml 2 points 4 days ago

Wanna check if a variable’s set to something expected? if [[ <test goes here> ]]; then <handle>; fi

Hey, you can't just leave out "test goes here". That's worst part by a long shot.
The rest of the syntax, I will have to look up every time I try to write it, but at least I can mostly guess what it does when reading. The test syntax on the other hand is just impossible to read without looking it up.

I also don't actually know how to look that up for the double brackets, so that's fun. For the single bracket, it took me years to learn that that's actually a command and you can do man [ to view the documentation.

[-] Badland9085@lemm.ee 1 points 4 days ago

To be fair, you don’t always have to use the [[ syntax. I know I don’t, e.g. if I’m just looking for a command that returns 1 or 0, which happens quite a bit if you get to use grep.

That said, man test is my friend.

But I’ve also gotten so used to using it that I remember -z and -n by heart :P

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[-] MajorHavoc@programming.dev 2 points 4 days ago* (last edited 4 days ago)

A few responses for you:

  • I deeply despise bash (edit: this was hyperbole. I also deeply appreciate bash, as is appropriate for something that has made my life better for free!). That Linux shell defaults settled on it is an embarrassment to the entire open source community. (Edit: but Lexers and Parsers are hard! You don't see me fixing it, so yes, I'll give it a break. I still have to be discerning for production use, of course.)
  • Yes, Bash is good enough for production. It is the world's current default shell. As long as we avoid it's fancier features (which all suck for production use), a quick bash script is often the most reasonable choice.
  • For the love of all that is holy, put your own personal phone number and no one else's in the script, if you choose to use bash to access a datatbase. There's thousands of routine ways that database access can hiccup, and bash is suitable to help you diagnose approximately 0% of them.
  • If I found out a colleague had used bash for database access in a context that I would be expected to co-maintain, I would start by plotting their demise, and then talk myself down to having a severe conversation with them - after I changed it immediately to something else, in production, ignoring all change protocols. (Invoking emergency change protocols.)

Edit: I can't even respond to the security concerns aspect of this. Choice of security tool affects the quality of protection. In this unfortunate analogy, Bash is "the pull out method". Don't do that anywhere that it matters, or anywhere that one can be fired for security violations.

(Edit 2: Others have mentioned invoking SQL DB cleanup scripts from bash. I have no problem with that. Letting bash or cron tell the DB and a static bit of SQL to do their usual thing has been fine for me, as well. The nightmare scenario I was imagining was bash gathering various inputs to the SQL and then invoking them. I've had that pattern blow up in my face, and had a devil of a time putting together what went wrong. It also comes with security concerns, as bash is normally a completely trusted running environment, and database input often come from untrusted sources.)

[-] NegativeLookBehind@lemmy.world 3 points 4 days ago

Why internet man hate Bash? Bash do many thing. Make computer work.

[-] MajorHavoc@programming.dev 1 points 4 days ago* (last edited 4 days ago)

I actually (also) love bash, and use it like crazy.

What I really hate is that bash is so locked in legacy that it's bad features (on a scripting language scale, which isn't fair) (and of which there are too many to enumerate) are now locked in permanently.

I also hate how convention has kept other shells from replacing bash's worst features with better modern alternatives.

To some extent, I'm railing against how hard it is to write a good Lexer and a Parser, honestly. Now that bash is stable, there's little interest in improving it. Particularly since one can just invoke a better scripting language for complex work.

I mourn the sweet spot that Perl occupies, that Bash and Python sit on either side of, looking longingly across the gap that separated their practical use cases.

I have lost hope that Python will achieve shell script levels of pragmatism. Although the invoke library is a frigging cool attempt.

But I hold on to my sorrow and anger that Bash hasn't bridged the gap, and never will, because whatever it can invoke, it's methods of responding to that invocation are trapped in messes like "if...fi".

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[-] thirteene@lemmy.world 1 points 4 days ago* (last edited 2 days ago)

Pretty much all languages are middleware, and most of the original code was shell/bash. All new employees in platform/devops want to immediately push their preferred language, they want java and rust environments. It's a pretty safe bet if they insist on using a specific language; then they don't know how awk or sed. Bash has all the tools you need, but good developers understand you write libraries for functionality that's missing. Modern languages like Python have been widely adopted and has a friendlier onboarding and will save you time though.

Saw this guy's post in another thread, he's strawmanning because of lack of knowledge.

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[-] Kissaki@programming.dev 1 points 4 days ago

In your own description you added a bunch of considerations, requirements of following specific practices, having specific knowledge, and a ton of environmental requirements.

For simple scripts or duck tape schedules all of that is fine. For anything else, I would be at least mindful if not skeptical of bash being a good tool for the job.

Bash is installed on all linux systems. I would not be very concerned about some dependencies like sqlite, if that is what you're using. But very concerned about others, like jq, which is an additional tool and requirement where you or others will eventually struggle with diffuse dependencies or managing a managed environment.

Even if you query sqlite or whatever tool with the command line query tool, you have to be aware that getting a value like that into bash means you lose a lot of typing and structure information. That's fine if you get only one or very few values. But I would have strong aversions when it goes beyond that.

You seem to be familiar with Bash syntax. But others may not be. It's not a simple syntax to get into and intuitively understand without mistakes. There's too many alternatives of if-ing and comparing values. It ends up as magic. In your example, if you read code, you may guess that :- means fallback, but it's not necessarily obvious. And certainly not other magic flags and operators.


As an anecdote, I guess the most complex thing I have done with Bash was scripting a deployment and starting test-runs onto a distributed system (and I think collecting results? I don't remember). Bash was available and copying and starting processes via ssh was simple and robust enough. Notably, the scope and env requirements were very limited.

[-] palordrolap@fedia.io 2 points 4 days ago

You seem to be familiar with Bash syntax. But others may not be.

If by this you mean that the Bash syntax for doing certain things is horrible and that it could be expressed more clearly in something else, then yes, I agree, otherwise I'm not sure this is a problem on the same level as others.

OP could pick any language and have the same problem. Except maybe Python, but even that strays into symbolic line noise once a project gets big enough.

Either way, comments can be helpful when strange constructs are used. There are comments in my own Bash scripts that say what a line is doing rather than just why precisely because of this.

But I think the main issue with Bash (and maybe other shells), is that it's parsed and run line by line. There's nothing like a full script syntax check before the script is run, which most other languages provide as a bare minimum.

[-] Kissaki@programming.dev 1 points 3 days ago

OP could pick any language and have the same problem. Except maybe Python, but even that strays into symbolic line noise once a project gets big enough.

Personally, I don't see python far off from bash. Decent for small scripts, bad for anything bigger. While not necessarily natively available, it's readily available and more portable (Windows), and has a rich library ecosystem.

Personally, I dislike the indent syntax. And the various tooling and complexities don't feel approachable or stable, and structuring not good.

But maybe that's me. Many people seem to enjoy or reach for python even for complex systems.

More structured and stable programming languages do not have these issues.

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this post was submitted on 15 Jan 2025
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