Files
Rocketmc/daedalus/src/lib.rs
2021-10-09 14:04:45 -07:00

128 lines
4.2 KiB
Rust

//! # Daedalus
//!
//! Daedalus is a library which provides models and methods to fetch metadata about games
#![warn(missing_docs, unused_import_braces, missing_debug_implementations)]
/// Models and methods for fetching metadata for the Fabric mod loader
pub mod fabric;
/// Models and methods for fetching metadata for Minecraft
pub mod minecraft;
#[derive(thiserror::Error, Debug)]
/// An error type representing possible errors when fetching metadata
pub enum Error {
#[error("Failed to validate file checksum at url {url} with hash {hash} after {tries} tries")]
/// A checksum was failed to validate for a file
ChecksumFailure {
/// The checksum's hash
hash: String,
/// The URL of the file attempted to be downloaded
url: String,
/// The amount of tries that the file was downloaded until failure
tries: u32,
},
/// There was an error while deserializing metadata
#[error("Error while deserializing JSON")]
SerdeError(#[from] serde_json::Error),
/// There was a network error when fetching an object
#[error("Unable to fetch {item}")]
FetchError {
/// The internal reqwest error
inner: reqwest::Error,
/// The item that was failed to be fetched
item: String,
},
/// There was an error when managing async tasks
#[error("Error while managing asynchronous tasks")]
TaskError(#[from] tokio::task::JoinError),
/// Error while parsing input
#[error("{0}")]
ParseError(String),
}
/// Converts a maven artifact to a path
pub fn get_path_from_artifact(artifact: &str) -> Result<String, Error> {
let name_items = artifact.split(':').collect::<Vec<&str>>();
let package = name_items.get(0).ok_or_else(|| {
Error::ParseError(format!("Unable to find package for library {}", &artifact))
})?;
let name = name_items.get(1).ok_or_else(|| {
Error::ParseError(format!("Unable to find name for library {}", &artifact))
})?;
let version = name_items.get(2).ok_or_else(|| {
Error::ParseError(format!("Unable to find version for library {}", &artifact))
})?;
Ok(format!(
"{}/{}/{}-{}.jar",
package.replace(".", "/"),
version,
name,
version
))
}
/// Downloads a file with retry and checksum functionality
pub async fn download_file(url: &str, sha1: Option<&str>) -> Result<bytes::Bytes, Error> {
let client = reqwest::Client::builder()
.tcp_keepalive(Some(std::time::Duration::from_secs(10)))
.build()
.map_err(|err| Error::FetchError {
inner: err,
item: url.to_string(),
})?;
for attempt in 1..=4 {
let result = client.get(url).send().await;
match result {
Ok(x) => {
let bytes = x.bytes().await;
if let Ok(bytes) = bytes {
if let Some(sha1) = sha1 {
if &*get_hash(bytes.clone()).await? != sha1 {
if attempt <= 3 {
continue;
} else {
return Err(Error::ChecksumFailure {
hash: sha1.to_string(),
url: url.to_string(),
tries: attempt,
});
}
}
}
return Ok(bytes);
} else if attempt <= 3 {
continue;
} else if let Err(err) = bytes {
return Err(Error::FetchError {
inner: err,
item: url.to_string(),
});
}
}
Err(_) if attempt <= 3 => continue,
Err(err) => {
return Err(Error::FetchError {
inner: err,
item: url.to_string(),
})
}
}
}
unreachable!()
}
/// Computes a checksum of the input bytes
pub async fn get_hash(bytes: bytes::Bytes) -> Result<String, Error> {
let hash = tokio::task::spawn_blocking(|| sha1::Sha1::from(bytes).hexdigest()).await?;
Ok(hash)
}