shell-string
Simple CLI to perform common string operations
Usage
shell-string 0.2.1
Cli for common string operations. Takes input from stdin.
USAGE:
string <SUBCOMMAND>
FLAGS:
-h, --help Prints help information
-V, --version Prints version information
SUBCOMMANDS:
help Prints this message or the help of the given subcommand(s)
length Returns the length the input string
line Pick a single line by linenumber
replace Replace all matching words
split Split up a string by a separator and print the parts on separate lines
substr Extract a part of a given string
template Useful for templating, replace sections of input with the output of a shell command or script
Why does this exists
I'm writing ci pipelines from time to time and manipulating strings, especially templating anything, always is a HUGE pain.
Every coworker has his own style solving a problem and when it comes down to string transformation any solution not written by yourself is sheer unmaintainable.
This is mostly because there are thousands of ways to do the tasks shell-string
does, but this cli makes them very obvious and easy to understand.
More than anything I hated finding some solution for file templating over and over again. I wrote shell-string
to never again have to think about what the best way of templating a file is.
It's always this, period.
Why is shell-string
good for templating files?
Because you practically have no restrictions. You have the full power of any shell command at hand, even javascript if you want. Basically you can write the stuff you have to substitute in any language you want. You can even use this to write your own substitution style of doing things. Most importantly, you don't have to.
How does that look?
kind: Deployment
metadata:
name: -deployment
labels:
deployed: "{{date}}"
app:
spec:
replicas:
...
image:
...
Per default sh
is used to interpret the command inside {{
and }}
and, if these delimeters don't suite your style, that's okay. You can choose any delimiter you fancy. And you should.
How am using a document as a template?
give you have a document deployment.template.yaml
and you want to derive a file called deployment.yaml
, that's easy. Open a terminal and type
cat deployment.template.yaml | string template > deployment.yaml
which means
cat deployment.template.yaml
: Print the filedeployment.template.yaml
| string template
: The|
means "don't print this in a terminal, pipe it to another programm" and that programm isstring
intemplate
mode.> deployment.yaml
: Write the output of this into a file calleddeployment.yaml
. If the file existed, empty it beforehand.
Installation
Given cargo is installed on your machine execute
cargo install shell-string
To verify your installation worked type string -v
and you should see the appropriate version number.
if you want the very latest version, check out this repository locally using
git clone https://github.com/nilsmartel/string
and build and install the code using
cd string # go into the repository
cargo install --path . --force # use force in case the binary is alread installed