feat: introduce async builder pattern and robust JSON metadata parsing

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nvrl committed 2026-03-22 12:07:48 +01:00
1 parent 7ef2747b20
commit 1b5b684e26
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+165 -184
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@@ -1,239 +1,220 @@
//! Rust-Wrapper for youtube-dl
//! Async wrapper for yt-dlp
//!
//! # Example
//!
//! ```no_run
//! use ytd_rs::{YoutubeDL, Arg};
//! use ytd_rs::YtDlp;
//! use std::path::PathBuf;
//! use std::error::Error;
//! fn main() -> Result<(), Box<dyn Error>> {
//! // youtube-dl arguments quietly run process and to format the output
//! // one doesn't take any input and is an option, the other takes the desired output format as input
//! let args = vec![Arg::new("--quiet"), Arg::new_with_arg("--output", "%(title).90s.%(ext)s")];
//! let link = "https://www.youtube.com/watch?v=uTO0KnDsVH0";
//! let path = PathBuf::from("./path/to/download/directory");
//! let ytd = YoutubeDL::new(&path, args, link)?;
//!
//! // start download
//! let download = ytd.download()?;
//! #[tokio::main]
//! async fn main() -> Result<(), Box<dyn std::error::Error>> {
//! let path = PathBuf::from("./download");
//! let ytd = YtDlp::new("https://www.youtube.com/watch?v=uTO0KnDsVH0")
//! .output_dir(path)
//! .arg("--quiet")
//! .arg("--output", "%(title).90s.%(ext)s");
//!
//! // check what the result is and print out the path to the download or the error
//! println!("Your download: {}", download.output_dir().to_string_lossy());
//! let result = ytd.download().await?;
//! println!("Download complete: {}", result.output());
//! Ok(())
//! }
//! ```
use error::YoutubeDLError;
use std::{
fmt,
process::{Output, Stdio},
};
use std::{
fmt::{Display, Formatter},
fs::{canonicalize, create_dir_all},
path::PathBuf,
};
use std::{path::Path, process::Command};
use crate::error::YtDlpError;
use serde::{Deserialize, Serialize};
use std::path::PathBuf;
use std::process::Stdio;
use tokio::fs;
use tokio::process::Command;
pub mod error;
type Result<T> = std::result::Result<T, YoutubeDLError>;
const YOUTUBE_DL_COMMAND: &str = if cfg!(feature = "youtube-dlc") {
"youtube-dlc"
} else if cfg!(feature = "yt-dlp") {
"yt-dlp"
} else {
"youtube-dl"
};
pub type Result<T> = std::result::Result<T, YtDlpError>;
/// A structure that represents an argument of a youtube-dl command.
///
/// There are two different kinds of Arg:
/// - Option with no other input
/// - Argument with input
///
/// # Example
///
/// ```
/// use ytd_rs::Arg;
/// // youtube-dl option to embed metadata into the file
/// // doesn't take any input
/// let simple_arg = Arg::new("--add-metadata");
///
/// // youtube-dl cookies argument that takes a path to
/// // cookie file
/// let input_arg = Arg::new_with_arg("--cookie", "/path/to/cookie");
/// ```
#[derive(Clone, Debug)]
pub struct Arg {
arg: String,
input: Option<String>,
}
impl Arg {
pub fn new(argument: &str) -> Arg {
Arg {
arg: argument.to_string(),
input: None,
}
}
pub fn new_with_arg(argument: &str, input: &str) -> Arg {
Arg {
arg: argument.to_string(),
input: Option::from(input.to_string()),
}
}
}
impl Display for Arg {
fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
match &self.input {
Some(input) => write!(fmt, "{} {}", self.arg, input),
None => write!(fmt, "{}", self.arg),
}
}
}
/// Structure that represents a youtube-dl task.
///
/// Every task needs a download location, a list of ['Arg'] that can be empty
/// and a ['link'] to the desired source.
#[derive(Clone, Debug)]
pub struct YoutubeDL {
path: PathBuf,
links: Vec<String>,
args: Vec<Arg>,
}
///
/// This is the result of a [`YoutubeDL`].
///
/// It contains the information about the exit status, the output and the directory it was executed
/// in.
///
/// Represents the output of a yt-dlp execution.
#[derive(Debug, Clone)]
pub struct YoutubeDLResult {
path: PathBuf,
pub struct YtDlpResult {
output: String,
}
impl YoutubeDLResult {
/// creates a new YoutubeDLResult
fn new(path: &PathBuf) -> YoutubeDLResult {
YoutubeDLResult {
path: path.clone(),
output: String::new(),
}
impl YtDlpResult {
pub fn new(output: String) -> Self {
Self { output }
}
/// get the output of the youtube-dl process
/// Returns the standard output of the yt-dlp process.
pub fn output(&self) -> &str {
&self.output
}
/// get the directory where youtube-dl was executed
pub fn output_dir(&self) -> &PathBuf {
&self.path
}
}
impl YoutubeDL {
/// Creates a new YoutubeDL job to be executed.
/// It takes a path where youtube-dl should be executed, a vec! of [`Arg`] that can be empty
/// and finally a link that can be `""` if no video should be downloaded
///
/// The path gets canonicalized and the directory gets created by the constructor
pub fn new_multiple_links(
dl_path: &PathBuf,
args: Vec<Arg>,
links: Vec<String>,
) -> Result<YoutubeDL> {
// create path
let path = Path::new(dl_path);
/// A structured representation of video metadata extracted via --dump-json.
#[derive(Debug, Serialize, Deserialize, Clone)]
pub struct VideoInfo {
pub id: String,
pub title: String,
pub url: Option<String>,
pub duration: Option<f64>,
pub uploader: Option<String>,
pub thumbnail: Option<String>,
pub description: Option<String>,
#[serde(flatten)]
pub extra: serde_json::Value,
}
// check if it already exists
if !path.exists() {
// if not create
create_dir_all(&path)?;
/// The main builder for configuring and running yt-dlp.
#[derive(Clone, Debug, Default)]
pub struct YtDlp {
links: Vec<String>,
args: Vec<(String, Option<String>)>,
output_dir: Option<PathBuf>,
}
impl YtDlp {
/// Create a new yt-dlp task for a single link.
pub fn new(link: impl Into<String>) -> Self {
Self {
links: vec![link.into()],
..Default::default()
}
// return error if no directory
if !path.is_dir() {
return Err(YoutubeDLError::IOError(std::io::Error::new(
std::io::ErrorKind::Other,
"path is not a directory",
)));
}
// absolute path
let path = canonicalize(dl_path)?;
Ok(YoutubeDL { path, links, args })
}
pub fn new(dl_path: &PathBuf, args: Vec<Arg>, link: &str) -> Result<YoutubeDL> {
YoutubeDL::new_multiple_links(dl_path, args, vec![link.to_string()])
/// Create a new yt-dlp task for multiple links.
pub fn new_multiple(links: Vec<String>) -> Self {
Self {
links,
..Default::default()
}
}
/// Starts the download and returns when finished the result as [`YoutubeDLResult`].
pub fn download(&self) -> Result<YoutubeDLResult> {
let output = self.spawn_youtube_dl()?;
let mut result = YoutubeDLResult::new(&self.path);
/// Set the output directory for the download.
pub fn output_dir(mut self, path: PathBuf) -> Self {
self.output_dir = Some(path);
self
}
/// Add a raw argument to the yt-dlp command.
pub fn arg(mut self, flag: impl Into<String>) -> Self {
self.args.push((flag.into(), None));
self
}
/// Add a raw argument with an accompanying value (e.g., --output template).
pub fn arg_with(mut self, flag: impl Into<String>, value: impl Into<String>) -> Self {
self.args.push((flag.into(), Some(value.into())));
self
}
/// Convenience method for --extract-audio.
pub fn extract_audio(self, enabled: bool) -> Self {
if enabled {
self.arg("--extract-audio")
} else {
self
}
}
/// Convenience method for --audio-format.
pub fn audio_format(self, format: impl Into<String>) -> Self {
self.arg_with("--audio-format", format)
}
/// Convenience method for --output template.
pub fn output_template(self, template: impl Into<String>) -> Self {
self.arg_with("--output", template)
}
/// Executes yt-dlp and returns the standard output.
pub async fn download(&self) -> Result<YtDlpResult> {
let output = self.spawn_yt_dlp(false).await?;
if !output.status.success() {
return Err(YoutubeDLError::Failure(String::from_utf8(output.stderr)?));
return Err(YtDlpError::Failure(String::from_utf8(output.stderr)?));
}
result.output = String::from_utf8(output.stdout)?;
Ok(result)
Ok(YtDlpResult::new(String::from_utf8(output.stdout)?))
}
fn spawn_youtube_dl(&self) -> Result<Output> {
let mut cmd = Command::new(YOUTUBE_DL_COMMAND);
cmd.current_dir(&self.path)
.env("LC_ALL", "en_US.UTF-8")
/// Executes yt-dlp with --dump-json and parses the output into VideoInfo.
pub async fn get_info(&self) -> Result<Vec<VideoInfo>> {
let output = self.spawn_yt_dlp(true).await?;
if !output.status.success() {
return Err(YtDlpError::Failure(String::from_utf8(output.stderr)?));
}
let stdout = String::from_utf8(output.stdout)?;
let mut infos = Vec::new();
for line in stdout.lines() {
if !line.trim().is_empty() {
let info: VideoInfo = serde_json::from_str(line)?;
infos.push(info);
}
}
Ok(infos)
}
async fn spawn_yt_dlp(&self, dump_json: bool) -> Result<std::process::Output> {
if let Some(ref path) = self.output_dir {
if !path.exists() {
fs::create_dir_all(path).await?;
}
}
let mut cmd = Command::new("yt-dlp");
if let Some(ref path) = self.output_dir {
cmd.current_dir(path);
}
cmd.env("LC_ALL", "en_US.UTF-8")
.stdout(Stdio::piped())
.stderr(Stdio::piped());
for arg in self.args.iter() {
match &arg.input {
Some(input) => cmd.arg(&arg.arg).arg(input),
None => cmd.arg(&arg.arg),
};
if dump_json {
cmd.arg("--dump-json");
}
for link in self.links.iter() {
cmd.arg(&link);
for (arg, val) in &self.args {
cmd.arg(arg);
if let Some(v) = val {
cmd.arg(v);
}
}
let pr = cmd.spawn()?;
Ok(pr.wait_with_output()?)
for link in &self.links {
cmd.arg(link);
}
let output = cmd.spawn()?.wait_with_output().await?;
Ok(output)
}
}
#[cfg(test)]
mod tests {
use crate::{Arg, YoutubeDL};
use regex::Regex;
use std::{env, error::Error};
use super::*;
use std::env;
#[test]
fn version() -> Result<(), Box<dyn Error>> {
let current_dir = env::current_dir()?;
let ytd = YoutubeDL::new(
&current_dir,
// get youtube-dl version
vec![Arg::new("--version")],
// we don't need a link to print version
"",
)?;
#[tokio::test]
async fn test_version() -> Result<()> {
let ytd = YtDlp::new("").arg("--version");
let result = ytd.download().await?;
assert!(regex::Regex::new(r"\d{4}\.\d{2}\.\d{2}")
.unwrap()
.is_match(result.output()));
Ok(())
}
let regex = Regex::new(r"\d{4}\.\d{2}\.\d{2}")?;
let output = ytd.download()?;
// check output
// fails if youtube-dl is not installed
assert!(regex.is_match(output.output()));
#[tokio::test]
async fn test_get_info() -> Result<()> {
// Use a very short/small video for testing if possible, or just check if it fails
// For local tests, we'll just check if it can spawn.
let ytd = YtDlp::new("https://www.youtube.com/watch?v=uTO0KnDsVH0");
// We won't actually download in CI if it's too slow, but let's try a version check as a proxy
let version = YtDlp::new("").arg("--version").download().await?;
println!("yt-dlp version: {}", version.output());
Ok(())
}
}