13 releases
new 0.1.13 | Sep 24, 2023 |
---|---|
0.1.12 | Sep 23, 2023 |
#326 in Command-line interface
300 downloads per month
1.5MB
5K
SLoC
r3bl_tuify
- What does it do?
- How to use it as a library?
- How to use it as a binary?
- Build, run, test tasks
- References
What does it do?
This crate can be used in two ways:
- As a library. This is useful if you want to add simple interactivity to your CLI app written in
Rust. You can see an example of this in the
examples
folder in themain_interactive.rs
file. You can run it usingcargo run --example main_interactive
. - As a binary. This is useful if you want to use this crate as a command line tool. The binary
target is called
rt
.
How to use it as a library?
Here's a demo of the library target of this crate in action.
The following example illustrates how you can use this as a library. The function that does the work
of rendering the UI is called select_from_list
. It takes a list of
items, and returns the selected item or items (depending on the selection mode). If the user does
not select anything, it returns None
. The function also takes the maximum height and width of the
display, and the selection mode (single select or multiple select).
It works on macOS, Linux, and Windows. And is aware of terminal color output limitations of each. For eg, it uses Windows API on Windows for keyboard input. And on macOS Terminal.app it restricts color output to a 256 color palette.
Currently only single selection is implemented. An issue is open to add this feature: https://github.com/r3bl-org/r3bl_rs_utils/issues if you would like to contribute.
use r3bl_rs_utils_core::*;
use r3bl_tuify::*;
use std::io::Result;
fn main() -> Result<()> {
// Get display size.
let max_width_col_count: usize = get_size().map(|it| it.col_count).unwrap_or(ch!(80)).into();
let max_height_row_count: usize = 5;
let user_input = select_from_list(
"Select an item".to_string(),
[
"item 1", "item 2", "item 3", "item 4", "item 5", "item 6", "item 7", "item 8",
"item 9", "item 10",
]
.iter()
.map(|it| it.to_string())
.collect(),
max_height_row_count,
max_width_col_count,
SelectionMode::Single,
StyleSheet::default(),
);
match &user_input {
Some(it) => {
println!("User selected: {:?}", it);
}
None => println!("User did not select anything"),
}
Ok(())
}
How to use it as a binary?
Here's a demo of the binary target of this crate in action.
You can install the binary using cargo install r3bl_tuify
(from crates.io). Or
cargo install --path .
from source. Once installed, you can rt
is a command line tool that
allows you to select one of the options from the list that is passed into it via stdin
. It
supports both stdin
and stdout
piping.
Here are the command line arguments that it accepts:
-s
or--selection-mode
- Allows you to select the selection mode. There are two options:single
andmultiple
.-c
or--command-to-run-with-selection
- Allows you to specify the command to run with the selected item. For example"echo foo \'%\'"
simply prints each selected item.-t
or--tui-height
- Optionally allows you to set the height of the TUI. The default is 5.
Currently only single selection is implemented. An issue is open to add this feature: https://github.com/r3bl-org/r3bl_rs_utils/issues if you would like to contribute.
Interactive user experience
Typically a CLI app is not interactive. You can pass commands, subcommands, options, and arguments to it, but if you get something wrong, then you get an error, and have to start all over again. This "conversation" style interface might require a lot of trial and error to get the desired result.
The following is an example of using the binary with many subcommands, options, and arguments.
cat TODO.todo | cargo run -- select-from-list \
--selection-mode single \
--command-to-run-with-each-selection "echo %"
Here's a video of this in action.
https://github.com/r3bl-org/r3bl_rs_utils/assets/2966499/c9b49bfb-b811-460e-a844-fe260eaa860a
What does this do?
cat TODO.todo
- prints the contents of theTODO.todo
file tostdout
.|
- pipes the output of the previous command to the next command, which isrt
(ie, the binary target of this crate).cargo run --
- runs thert
debug binary in the target folder.select-from-list
- runs thert
binary with theselect-from-list
subcommand. This subcommand requires 2 arguments:--selection-mode
and--command-to-run-with-each-selection
. Whew! This is getting long!--selection-mode single
- sets the selection mode tosingle
. This means that the user can only select one item from the list. What list? The list that is piped in from the previous command (ie,cat TODO.todo
).--command-to-run-with-each-selection "echo %"
- sets the command to run with each selection. In this case, it isecho %
. The%
is a placeholder for the selected item. So if the user selectsitem 1
, then the command that will be run isecho item 1
. Theecho
command simply prints the selected item tostdout
.
Now that is a lot to remember. It is helpful to use clap
to provide nice command line help but
that is still quite a few things that you have to get right in order for this command to work.
It doesn't have to be this way. It is entirely possible for the binary to be interactive along with
the use of clap
to specify some of the subcommands, and arguments. It doesn't have to be an all or
nothing approach. We can have the best of both worlds. The following videos illustrate what happens
when:
-
--selection-mode
and--command-to-run-with-each-selection
are not passed in the command line.cat TODO.todo | cargo run -- select-from-list
Here are the 3 scenarios that can happen:
-
The user first chooses
single
selection mode (using a list selection component), and then types inecho %
in the terminal, as the command to run with each selection. This is the really interactive scenario, since the user has to provide 2 pieces of information: the selection mode, and the command to run with each selection. They didn't provide this up front when they ran the command.https://github.com/r3bl-org/r3bl_rs_utils/assets/2966499/51de8867-513b-429f-aff2-63dd25d71c82
-
Another scenario is that the user does not provide the required information even when prompted interactively. In this scenario, the program exits with an error and help message.
Here they don't provide what
selection-mode
they want. And they don't provide whatcommand-to-run-with-each-selection
they want. Without this information the program can't continue, so it exits and provides some help message.https://github.com/r3bl-org/r3bl_rs_utils/assets/2966499/664d0367-90fd-4f0a-ad87-3f4745642ad0
-
-
--selection-mode
is not passed in the command line. So it only interactively prompts the user for this piece of information. Similarly, if the user does not provide this information, the app exits and provides a help message.cat TODO.todo | cargo run -- select-from-list --command-to-run-with-each-selection "echo %"
https://github.com/r3bl-org/r3bl_rs_utils/assets/2966499/be65d9b2-575b-47c0-8291-110340bd2fe7
-
--command-to-run-with-each-selection
is not passed in the command line. So it only interactively prompts the user for this piece of information. Similarly, if the user does not provide this information, the app exits and provides a help message.cat TODO.todo | cargo run -- select-from-list --selection-mode single
https://github.com/r3bl-org/r3bl_rs_utils/assets/2966499/d8d7d419-c85e-4c10-bea5-345aa31a92a3
Paths
There are a lot of different execution paths that you can take with this relatively simple program. Here is a list.
-
Happy paths:
rt
- prints help.cat Cargo.toml | rt -s single -c "echo foo \'%\'"
-stdin
is piped in, and it prints the user selected option tostdout
.cat Cargo.toml | rt -s multiple -c "echo foo \'%\'"
-stdin
is piped in, and it prints the user selected option tostdout
.
-
Unhappy paths (
stdin
is not piped in and, orstdout
is piped out):rt -s single
- expectsstdin
to be piped in, and prints help.rt -s multiple
- expectsstdin
to be piped in, and prints help.ls -la | rt -s single | xargs -0
- does not expectstdout
to be piped out, and prints help.ls -la | rt -s multiple | xargs -0
- does not expectstdout
to be piped out, and prints help.
Due to the way in which unix pipes are implemented, it is not possible to pipe the
stdout
of this command to anything else. Unix pipes are non blocking. So there is no way to stop the pipe "mid way". This is whyrt
displays an error when thestdout
is piped out. It is not possible to pipe thestdout
ofrt
to another command. Instead, thert
binary simply takes a command that it will run after the user has made their selection. Using the selected item(s) and applying them to this command.
Build, run, test tasks
Prerequisites
🌠 In order for these to work you have to install the Rust toolchain, nu
, cargo-watch
,
bat
, and flamegraph
on your system. Here are the instructions:
- Install the Rust toolchain using
rustup
by following the instructions here. - Install
cargo-watch
usingcargo install cargo-watch
. - Install
flamegraph
usingcargo install flamegraph
. - Install
bat
usingcargo install bat
. - Install
nu
shell on your system usingcargo install nu
. It is available for Linux, macOS, and Windows.
Nu shell script to make, build, run, etc.
Command | Description |
---|---|
nu run.nu run |
Run examples |
nu run.nu run-piped |
Run binary with piped input |
nu run.nu build |
Build |
nu run.nu clean |
Clean |
nu run.nu all |
All |
nu run.nu run-with-flamegraph-profiling |
Run examples with flamegraph profiling |
nu run.nu test |
Run tests |
nu run.nu clippy |
Run clippy |
nu run.nu docs |
Build docs |
nu run.nu serve-docs |
Serve docs over VSCode Remote SSH session. |
nu run.nu upgrade-deps |
Upgrade deps |
nu run.nu rustfmt |
Run rustfmt |
The following commands will watch for changes in the source folder and re-run:
Command | Description |
---|---|
nu run.nu watch-run |
Watch run |
nu run.nu watch-all-tests |
Watch all test |
nu run.nu watch-one-test <test_name> |
Watch one test |
nu run.nu watch-clippy |
Watch clippy |
nu run.nu watch-macro-expansion-one-test <test_name> |
Watch macro expansion for one test |
References
CLI UX guidelines:
- https://rust-cli-recommendations.sunshowers.io/handling-arguments.html
- https://rust-cli-recommendations.sunshowers.io/configuration.html
- https://rust-cli-recommendations.sunshowers.io/hierarchical-config.html
- https://rust-cli-recommendations.sunshowers.io/hierarchical-config.html
- https://docs.rs/clap/latest/clap/_derive/#overview
- https://clig.dev/#foreword
ANSI escape codes:
- https://notes.burke.libbey.me/ansi-escape-codes/
- https://en.wikipedia.org/wiki/ANSI_escape_code
- https://www.asciitable.com/
- https://commons.wikimedia.org/wiki/File:Xterm_256color_chart.svg
- https://www.ditig.com/256-colors-cheat-sheet
- https://stackoverflow.com/questions/4842424/list-of-ansi-color-escape-sequences
- https://www.compuphase.com/cmetric.htm
Dependencies
~15–56MB
~896K SLoC