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 withcurl
. 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 forjq
. - 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
ordebian
oralpine
, 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?
I don’t necessarily agree that all simple tasks will lead to the need for a test suite to accommodate more complex requirements. If it does reach that point,
I also don’t agree that you can just solder on whatever small task you have to whatever systems you already have up and running. That’s how you make a Frankenstein. Someone at some point will have to come do something about your little section because it started breaking, or causing other things to break. It could be throwing error messages because somebody changed the underlying db schema. It could be calling and retrying a network call and due to, perhaps, poorly configured backoff strategy, you’re tripping up monitoring alerts.
That said, I do agree on it suitable for temporary tasks.