#![deny(clippy::pedantic)]
#![deny(rust_2018_idioms)]
#![allow(clippy::missing_errors_doc)]
use std::{path::PathBuf, time::Duration};
use async_trait::async_trait;
use aws_sdk_s3::error::{GetObjectError, PutObjectError};
use aws_sdk_s3::{
model::ObjectCannedAcl, presigning::config::PresigningConfig, ByteStream, SdkError,
};
use bytes::Bytes;
use itertools::Itertools;
use serde::{Deserialize, Serialize};
use thiserror::Error;
use tokio::{
fs::File,
io::{AsyncReadExt, AsyncWriteExt},
};
#[derive(Debug, Error)]
pub enum Error {
#[error("failed to parse filesystem uri: {0}")]
UriParse(#[from] url::ParseError),
#[error("unknown filesystem kind (expected `s3` or `file`)")]
UnknownFileSystemKind,
#[error("failed to insert object to s3: {0}")]
S3Put(#[from] SdkError<PutObjectError>),
#[error("failed to get object from s3: {0}")]
S3Get(#[from] SdkError<GetObjectError>),
#[error("i/o failure: {0}")]
Io(#[from] std::io::Error),
#[error("failed to parse uuid: {0}")]
UuidParse(#[from] uuid::Error),
#[error("path missing from uri")]
MissingPath,
#[error("host missing from uri")]
MissingHost,
#[error("bucket missing from uri")]
MissingBucket,
#[error("invalid aws presigning config: {0}")]
AwsPresigningConfig(#[from] aws_sdk_s3::presigning::config::Error),
}
#[derive(Debug)]
pub enum FileSystem {
S3(S3),
Local(Local),
}
impl FileSystem {
pub async fn from_str(s: &str) -> Result<Self, Error> {
let uri = url::Url::parse(s)?;
Ok(match uri.scheme() {
"s3" => {
let shared_config = aws_config::load_from_env().await;
let client = aws_sdk_s3::Client::new(&shared_config);
let mut path = uri.path_segments().ok_or(Error::MissingPath)?;
Self::S3(S3 {
host: uri.host().ok_or(Error::MissingHost)?.to_string(),
bucket: path.next().ok_or(Error::MissingBucket)?.to_string(),
path: Itertools::intersperse(path, "/").collect(),
client,
})
}
"file" => Self::Local(Local {
path: uri.to_file_path().map_err(|()| Error::MissingPath)?,
}),
_ => return Err(Error::UnknownFileSystemKind),
})
}
pub async fn read(&self, file_ref: FileReference) -> Result<FilePointer, Error> {
match self {
Self::S3(v) => v.read(file_ref).await,
Self::Local(v) => v.read(file_ref).await,
}
}
pub async fn write(&self, data: Bytes) -> Result<FileReference, Error> {
match self {
Self::S3(v) => v.write(data).await,
Self::Local(v) => v.write(data).await,
}
}
}
#[derive(Debug, Serialize, Deserialize)]
pub enum FileSystemKind {
Local,
S3,
}
impl std::fmt::Display for FileSystemKind {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Self::Local => f.write_str("local"),
Self::S3 => f.write_str("s3"),
}
}
}
impl std::str::FromStr for FileSystemKind {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Error> {
match s {
"local" => Ok(Self::Local),
"s3" => Ok(Self::S3),
_ => Err(Error::UnknownFileSystemKind),
}
}
}
#[derive(Debug, Serialize, Deserialize)]
pub struct FileReference {
file_system: FileSystemKind,
reference: uuid::Uuid,
}
impl std::fmt::Display for FileReference {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}:{}", self.file_system, self.reference)
}
}
impl std::str::FromStr for FileReference {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let mut split = s.splitn(2, ':');
let file_system = FileSystemKind::from_str(split.next().unwrap_or_default())?;
let reference = uuid::Uuid::from_str(split.next().unwrap_or_default())?;
Ok(FileReference {
file_system,
reference,
})
}
}
#[derive(Debug, PartialEq, Eq)]
pub enum FilePointer {
Content(Vec<u8>),
Redirect(http::Uri),
}
#[async_trait]
pub trait FileSystemIo {
const KIND: FileSystemKind;
async fn read(&self, file_ref: FileReference) -> Result<FilePointer, Error>;
async fn write(&self, data: Bytes) -> Result<FileReference, Error>;
#[must_use]
fn create_ref() -> FileReference {
FileReference {
file_system: Self::KIND,
reference: uuid::Uuid::new_v4(),
}
}
}
#[derive(Debug)]
pub struct Local {
pub path: PathBuf,
}
#[async_trait]
impl FileSystemIo for Local {
const KIND: FileSystemKind = FileSystemKind::Local;
async fn read(&self, file_ref: FileReference) -> Result<FilePointer, Error> {
let path = self.path.join(file_ref.reference.to_string());
let mut file = File::open(path).await?;
let mut contents = vec![];
file.read_to_end(&mut contents).await?;
Ok(FilePointer::Content(contents))
}
async fn write(&self, data: Bytes) -> Result<FileReference, Error> {
let file_ref = Self::create_ref();
let path = self.path.join(file_ref.reference.to_string());
let mut file = File::create(path).await?;
file.write_all(&data).await?;
Ok(file_ref)
}
}
#[derive(Debug)]
pub struct S3 {
host: String,
bucket: String,
path: String,
client: aws_sdk_s3::Client,
}
#[async_trait]
impl FileSystemIo for S3 {
const KIND: FileSystemKind = FileSystemKind::S3;
async fn read(&self, file_ref: FileReference) -> Result<FilePointer, Error> {
Ok(FilePointer::Redirect(
self.client
.get_object()
.key(format!("{}/{}", self.path, file_ref.reference.to_string()))
.bucket(&self.bucket)
.presigned(PresigningConfig::expires_in(Duration::from_secs(600))?)
.await?
.uri()
.clone(),
))
}
async fn write(&self, data: Bytes) -> Result<FileReference, Error> {
let file_ref = Self::create_ref();
self.client
.put_object()
.key(format!("{}/{}", self.path, file_ref.reference.to_string()))
.content_md5(format!("{:x}", md5::compute(&data)))
.body(ByteStream::new(data.into()))
.bucket(&self.bucket)
.acl(ObjectCannedAcl::Private)
.send()
.await?;
Ok(file_ref)
}
}
#[cfg(test)]
mod tests {
use super::{FilePointer, FileSystem, FileSystemIo};
use bytes::Bytes;
#[tokio::test]
#[allow(clippy::pedantic)]
async fn parse_filesystem() {
assert!(matches!(
FileSystem::from_str("file:///tmp/chartered").await,
Ok(FileSystem::Local(inner)) if inner.path.to_str().unwrap() == "/tmp/chartered"
));
}
#[tokio::test]
#[allow(clippy::pedantic)]
async fn local() {
let fs = super::Local {
path: "/tmp".into(),
};
let file_ref = fs.write(Bytes::from_static(b"abcdef")).await.unwrap();
assert_eq!(
fs.read(file_ref).await.unwrap(),
FilePointer::Content(Vec::from(b"abcdef".as_ref()))
);
}
}