nushell/crates/nu-explore/src/explore.rs
Reilly Wood 3d340657b5
explore: adopt anyhow, support CustomValue, remove help system (#12692)
This PR:
1. Adds basic support for `CustomValue` to `explore`. Previously `open
foo.db | explore` didn't really work, now we "materialize" the whole
database to a `Value` before loading it
2. Adopts `anyhow` for error handling in `explore`. Previously we were
kind of rolling our own version of `anyhow` by shoving all errors into a
`std::io::Error`; I think this is much nicer. This was necessary because
as part of 1), collecting input is now fallible...
3. Removes a lot of `explore`'s fancy command help system.
- Previously each command (`:help`, `:try`, etc.) had a sophisticated
help system with examples etc... but this was not very visible to users.
You had to know to run `:help :try` or view a list of commands with
`:help :`
- As discussed previously, we eventually want to move to a less modal
approach for `explore`, without the Vim-like commands. And so I don't
think it's worth keeping this command help system around (it's
intertwined with other stuff, and making these changes would have been
harder if keeping it).
4. Rename the `--reverse` flag to `--tail`. The flag scrolls to the end
of the data, which IMO is described better by "tail"
5. Does some renaming+commenting to clear up things I found difficult to
understand when navigating the `explore` code


I initially thought 1) would be just a few lines, and then this PR blew
up into much more extensive changes 😅


## Before
The whole database was being displayed as a single Nuon/JSON line 🤔 

![image](https://github.com/nushell/nushell/assets/26268125/6383f43b-fdff-48b4-9604-398438ad1499)


## After
The database gets displayed like a record

![image](https://github.com/nushell/nushell/assets/26268125/2f00ed7b-a3c4-47f4-a08c-98d07efc7bb4)


## Future work

It is sort of annoying that we have to load a whole SQLite database into
memory to make this work; it will be impractical for large databases.
I'd like to explore improvements to `CustomValue` that can make this
work more efficiently.
2024-05-01 17:34:37 -05:00

348 lines
11 KiB
Rust

use crate::{
run_pager,
util::{create_lscolors, create_map, map_into_value},
PagerConfig, StyleConfig,
};
use nu_ansi_term::{Color, Style};
use nu_color_config::{get_color_map, StyleComputer};
use nu_engine::command_prelude::*;
use std::collections::HashMap;
/// A `less` like program to render a [`Value`] as a table.
#[derive(Clone)]
pub struct Explore;
impl Command for Explore {
fn name(&self) -> &str {
"explore"
}
fn usage(&self) -> &str {
"Explore acts as a table pager, just like `less` does for text."
}
fn signature(&self) -> nu_protocol::Signature {
// todo: Fix error message when it's empty
// if we set h i short flags it panics????
Signature::build("explore")
.input_output_types(vec![(Type::Any, Type::Any)])
.named(
"head",
SyntaxShape::Boolean,
"Show or hide column headers (default true)",
None,
)
.switch("index", "Show row indexes when viewing a list", Some('i'))
.switch(
"tail",
"Start with the viewport scrolled to the bottom",
Some('t'),
)
.switch(
"peek",
"When quitting, output the value of the cell the cursor was on",
Some('p'),
)
.category(Category::Viewers)
}
fn extra_usage(&self) -> &str {
r#"Press `:` then `h` to get a help menu."#
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let show_head: bool = call.get_flag(engine_state, stack, "head")?.unwrap_or(true);
let show_index: bool = call.has_flag(engine_state, stack, "index")?;
let tail: bool = call.has_flag(engine_state, stack, "tail")?;
let peek_value: bool = call.has_flag(engine_state, stack, "peek")?;
let ctrlc = engine_state.ctrlc.clone();
let nu_config = engine_state.get_config();
let style_computer = StyleComputer::from_config(engine_state, stack);
let mut config = nu_config.explore.clone();
include_nu_config(&mut config, &style_computer);
update_config(&mut config, show_index, show_head);
prepare_default_config(&mut config);
let style = style_from_config(&config);
let lscolors = create_lscolors(engine_state, stack);
let mut config = PagerConfig::new(nu_config, &style_computer, &lscolors, config);
config.style = style;
config.peek_value = peek_value;
config.tail = tail;
let result = run_pager(engine_state, &mut stack.clone(), ctrlc, input, config);
match result {
Ok(Some(value)) => Ok(PipelineData::Value(value, None)),
Ok(None) => Ok(PipelineData::Value(Value::default(), None)),
Err(err) => {
let shell_error = match err.downcast::<ShellError>() {
Ok(e) => e,
Err(e) => ShellError::GenericError {
error: e.to_string(),
msg: "".into(),
span: None,
help: None,
inner: vec![],
},
};
Ok(PipelineData::Value(
Value::error(shell_error, call.head),
None,
))
}
}
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Explore the system information record",
example: r#"sys | explore"#,
result: None,
},
Example {
description: "Explore the output of `ls` without column names",
example: r#"ls | explore --head false"#,
result: None,
},
Example {
description: "Explore a list of Markdown files' contents, with row indexes",
example: r#"glob *.md | each {|| open } | explore --index"#,
result: None,
},
Example {
description:
"Explore a JSON file, then save the last visited sub-structure to a file",
example: r#"open file.json | explore --peek | to json | save part.json"#,
result: None,
},
]
}
}
fn update_config(config: &mut HashMap<String, Value>, show_index: bool, show_head: bool) {
let mut hm = config.get("table").and_then(create_map).unwrap_or_default();
if show_index {
insert_bool(&mut hm, "show_index", show_index);
}
if show_head {
insert_bool(&mut hm, "show_head", show_head);
}
config.insert(String::from("table"), map_into_value(hm));
}
fn style_from_config(config: &HashMap<String, Value>) -> StyleConfig {
let mut style = StyleConfig::default();
let colors = get_color_map(config);
if let Some(s) = colors.get("status_bar_text") {
style.status_bar_text = *s;
}
if let Some(s) = colors.get("status_bar_background") {
style.status_bar_background = *s;
}
if let Some(s) = colors.get("command_bar_text") {
style.cmd_bar_text = *s;
}
if let Some(s) = colors.get("command_bar_background") {
style.cmd_bar_background = *s;
}
if let Some(hm) = config.get("status").and_then(create_map) {
let colors = get_color_map(&hm);
if let Some(s) = colors.get("info") {
style.status_info = *s;
}
if let Some(s) = colors.get("success") {
style.status_success = *s;
}
if let Some(s) = colors.get("warn") {
style.status_warn = *s;
}
if let Some(s) = colors.get("error") {
style.status_error = *s;
}
}
style
}
fn prepare_default_config(config: &mut HashMap<String, Value>) {
const STATUS_BAR: Style = color(
Some(Color::Rgb(29, 31, 33)),
Some(Color::Rgb(196, 201, 198)),
);
const INPUT_BAR: Style = color(Some(Color::Rgb(196, 201, 198)), None);
const HIGHLIGHT: Style = color(Some(Color::Black), Some(Color::Yellow));
const STATUS_ERROR: Style = color(Some(Color::White), Some(Color::Red));
const STATUS_INFO: Style = color(None, None);
const STATUS_SUCCESS: Style = color(Some(Color::Black), Some(Color::Green));
const STATUS_WARN: Style = color(None, None);
const TABLE_SPLIT_LINE: Style = color(Some(Color::Rgb(64, 64, 64)), None);
const TABLE_SELECT_CELL: Style = color(None, None);
const TABLE_SELECT_ROW: Style = color(None, None);
const TABLE_SELECT_COLUMN: Style = color(None, None);
const HEXDUMP_INDEX: Style = color(Some(Color::Cyan), None);
const HEXDUMP_SEGMENT: Style = color(Some(Color::Cyan), None).bold();
const HEXDUMP_SEGMENT_ZERO: Style = color(Some(Color::Purple), None).bold();
const HEXDUMP_SEGMENT_UNKNOWN: Style = color(Some(Color::Green), None).bold();
const HEXDUMP_ASCII: Style = color(Some(Color::Cyan), None).bold();
const HEXDUMP_ASCII_ZERO: Style = color(Some(Color::Purple), None).bold();
const HEXDUMP_ASCII_UNKNOWN: Style = color(Some(Color::Green), None).bold();
insert_style(config, "status_bar_background", STATUS_BAR);
insert_style(config, "command_bar_text", INPUT_BAR);
insert_style(config, "highlight", HIGHLIGHT);
// because how config works we need to parse a string into Value::Record
{
let mut hm = config
.get("status")
.and_then(parse_hash_map)
.unwrap_or_default();
insert_style(&mut hm, "info", STATUS_INFO);
insert_style(&mut hm, "success", STATUS_SUCCESS);
insert_style(&mut hm, "warn", STATUS_WARN);
insert_style(&mut hm, "error", STATUS_ERROR);
config.insert(String::from("status"), map_into_value(hm));
}
{
let mut hm = config
.get("table")
.and_then(parse_hash_map)
.unwrap_or_default();
insert_style(&mut hm, "split_line", TABLE_SPLIT_LINE);
insert_style(&mut hm, "selected_cell", TABLE_SELECT_CELL);
insert_style(&mut hm, "selected_row", TABLE_SELECT_ROW);
insert_style(&mut hm, "selected_column", TABLE_SELECT_COLUMN);
config.insert(String::from("table"), map_into_value(hm));
}
{
let mut hm = config
.get("hex-dump")
.and_then(create_map)
.unwrap_or_default();
insert_style(&mut hm, "color_index", HEXDUMP_INDEX);
insert_style(&mut hm, "color_segment", HEXDUMP_SEGMENT);
insert_style(&mut hm, "color_segment_zero", HEXDUMP_SEGMENT_ZERO);
insert_style(&mut hm, "color_segment_unknown", HEXDUMP_SEGMENT_UNKNOWN);
insert_style(&mut hm, "color_ascii", HEXDUMP_ASCII);
insert_style(&mut hm, "color_ascii_zero", HEXDUMP_ASCII_ZERO);
insert_style(&mut hm, "color_ascii_unknown", HEXDUMP_ASCII_UNKNOWN);
insert_int(&mut hm, "segment_size", 2);
insert_int(&mut hm, "count_segments", 8);
insert_bool(&mut hm, "split", true);
config.insert(String::from("hex-dump"), map_into_value(hm));
}
}
fn parse_hash_map(value: &Value) -> Option<HashMap<String, Value>> {
value.as_record().ok().map(|val| {
val.iter()
.map(|(col, val)| (col.clone(), val.clone()))
.collect::<HashMap<_, _>>()
})
}
const fn color(foreground: Option<Color>, background: Option<Color>) -> Style {
Style {
background,
foreground,
is_blink: false,
is_bold: false,
is_dimmed: false,
is_hidden: false,
is_italic: false,
is_reverse: false,
is_strikethrough: false,
is_underline: false,
prefix_with_reset: false,
}
}
fn insert_style(map: &mut HashMap<String, Value>, key: &str, value: Style) {
if map.contains_key(key) {
return;
}
if value == Style::default() {
return;
}
let value = nu_color_config::NuStyle::from(value);
if let Ok(val) = nu_json::to_string_raw(&value) {
map.insert(String::from(key), Value::string(val, Span::unknown()));
}
}
fn insert_bool(map: &mut HashMap<String, Value>, key: &str, value: bool) {
if map.contains_key(key) {
return;
}
map.insert(String::from(key), Value::bool(value, Span::unknown()));
}
fn insert_int(map: &mut HashMap<String, Value>, key: &str, value: i64) {
if map.contains_key(key) {
return;
}
map.insert(String::from(key), Value::int(value, Span::unknown()));
}
fn include_nu_config(config: &mut HashMap<String, Value>, style_computer: &StyleComputer) {
let line_color = lookup_color(style_computer, "separator");
if line_color != nu_ansi_term::Style::default() {
let mut map = config
.get("table")
.and_then(parse_hash_map)
.unwrap_or_default();
insert_style(&mut map, "split_line", line_color);
config.insert(String::from("table"), map_into_value(map));
}
}
fn lookup_color(style_computer: &StyleComputer, key: &str) -> nu_ansi_term::Style {
style_computer.compute(key, &Value::nothing(Span::unknown()))
}