use async_std::fs::{File, OpenOptions};
use async_std::io::{ErrorKind as IOErrorKind, BufReader};
use async_std::io::prelude::*;
use async_std::task::spawn_blocking;
use async_trait::async_trait;
use crate::database::{ErrorKind, Result, Storage, StorageError};
use fd_lock::RwLock;
use log::debug;
use std::path::{Path, PathBuf};
use std::collections::HashMap;
impl From<std::io::Error> for StorageError {
fn from(source: std::io::Error) -> Self {
Self::with_source(
match source.kind() {
IOErrorKind::NotFound => ErrorKind::NotFound,
_ => ErrorKind::Backend,
},
"file I/O error",
Box::new(source),
)
}
}
async fn get_lockable_file(file: File) -> RwLock<File> {
debug!("Trying to create a file lock");
spawn_blocking(move || RwLock::new(file)).await
}
fn url_to_path(root: &Path, url: &str) -> PathBuf {
let url = http_types::Url::parse(url).expect("Couldn't parse a URL");
let mut path: PathBuf = root.to_owned();
path.push(url.origin().ascii_serialization() + &url.path().to_string() + ".json");
path
}
fn modify_post(post: &serde_json::Value, update: &serde_json::Value) -> Result<serde_json::Value> {
let mut add_keys: HashMap<String, serde_json::Value> = HashMap::new();
let mut remove_keys: Vec<String> = vec![];
let mut remove_values: HashMap<String, Vec<serde_json::Value>> = HashMap::new();
let mut post = post.clone();
if let Some(delete) = update["delete"].as_array() {
remove_keys.extend(delete.iter().filter_map(|v| v.as_str()).map(|v| v.to_string()));
} else if let Some(delete) = update["delete"].as_object() {
for (k, v) in delete {
if let Some(v) = v.as_array() {
remove_values.entry(k.to_string()).or_default().extend(v.clone());
} else {
return Err(StorageError::new(ErrorKind::BadRequest, "Malformed update object"));
}
}
}
if let Some(add) = update["add"].as_object() {
for (k, v) in add {
if v.is_array() {
add_keys.insert(k.to_string(), v.clone());
} else {
return Err(StorageError::new(ErrorKind::BadRequest, "Malformed update object"));
}
}
}
if let Some(replace) = update["replace"].as_object() {
for (k, v) in replace {
remove_keys.push(k.to_string());
add_keys.insert(k.to_string(), v.clone());
}
}
for k in remove_keys {
post["properties"].as_object_mut().unwrap().remove(&k);
}
for (k, v) in remove_values {
let k = &k;
let props;
if k == "children" {
props = &mut post;
} else {
props = &mut post["properties"];
}
v.iter().for_each(|v| {
if let Some(vec) = props[k].as_array_mut() {
if let Some(index) = vec.iter().position(|w| w == v) {
vec.remove(index);
}
}
});
}
for (k, v) in add_keys {
let props;
if k == "children" {
props = &mut post;
} else {
props = &mut post["properties"];
}
let k = &k;
if let Some(prop) = props[k].as_array_mut() {
if k == "children" {
v.as_array().unwrap().iter().cloned().rev().for_each(|v| prop.insert(0, v));
} else {
prop.extend(v.as_array().unwrap().iter().cloned());
}
} else {
post["properties"][k] = v
}
}
Ok(post)
}
#[derive(Clone)]
pub struct FileStorage {
root_dir: PathBuf,
}
impl FileStorage {
pub async fn new(root_dir: PathBuf) -> Result<Self> {
// TODO check if the dir is writable
Ok(Self { root_dir })
}
}
#[async_trait]
impl Storage for FileStorage {
async fn post_exists(&self, url: &str) -> Result<bool> {
let path = url_to_path(&self.root_dir, url);
debug!("Checking if {:?} exists...", path);
Ok(spawn_blocking(move || path.is_file()).await)
}
async fn get_post(&self, url: &str) -> Result<Option<serde_json::Value>> {
let path = url_to_path(&self.root_dir, url);
debug!("Opening {:?}", path);
// We have to special-case in here because the function should return Ok(None) on 404
match File::open(path).await {
Ok(f) => {
let lock = get_lockable_file(f).await;
let guard = lock.read()?;
// HOW DOES THIS TYPECHECK?!!!!!!!!
// Read::read(&mut self) requires a mutable reference
// yet Read is implemented for &File
// We can't get a &mut File from &File, can we?
// And we need a &mut File to use Read::read_to_string()
// Yet if we pass it to a BufReader it works?!!
//
// I hate magic
//
// TODO find a way to get rid of BufReader here
let mut content = String::new();
let mut reader = BufReader::new(&*guard);
reader.read_to_string(&mut content).await?;
drop(reader);
drop(guard);
Ok(Some(serde_json::from_str(&content)?))
}
Err(err) => {
if err.kind() == IOErrorKind::NotFound {
Ok(None)
} else {
Err(err.into())
}
}
}
}
async fn put_post<'a>(&self, post: &'a serde_json::Value, user: &'a str) -> Result<()> {
let key = post["properties"]["uid"][0]
.as_str()
.expect("Tried to save a post without UID");
let path = url_to_path(&self.root_dir, key);
debug!("Creating {:?}", path);
let parent = path.parent().unwrap().to_owned();
if !spawn_blocking(move || parent.is_dir()).await {
async_std::fs::create_dir_all(path.parent().unwrap()).await?;
}
let f = OpenOptions::new()
.write(true)
.create_new(true)
.open(&path)
.await?;
let mut lock = get_lockable_file(f).await;
let mut guard = lock.write()?;
(*guard).write_all(post.to_string().as_bytes()).await?;
(*guard).flush().await?;
drop(guard);
if post["properties"]["url"].is_array() {
for url in post["properties"]["url"]
.as_array()
.unwrap()
.iter()
.map(|i| i.as_str().unwrap())
{
// TODO consider using the symlink crate
// to promote cross-platform compat on Windows
// do we even need to support Windows?...
if url != key && url.starts_with(user) {
let link = url_to_path(&self.root_dir, url);
debug!("Creating a symlink at {:?}", link);
let orig = path.clone();
spawn_blocking(move || { std::os::unix::fs::symlink(orig, link) }).await?;
}
}
}
Ok(())
}
async fn update_post<'a>(&self, url: &'a str, update: serde_json::Value) -> Result<()> {
let path = url_to_path(&self.root_dir, url);
let f = OpenOptions::new()
.write(true)
.read(true)
.truncate(false)
.open(&path)
.await?;
let mut lock = get_lockable_file(f).await;
let mut guard = lock.write()?;
let mut content = String::new();
guard.read_to_string(&mut content).await?;
let json: serde_json::Value = serde_json::from_str(&content)?;
// Apply the editing algorithms
let new_json = modify_post(&json, &update)?;
(*guard).set_len(0).await?;
(*guard).seek(std::io::SeekFrom::Start(0)).await?;
(*guard).write_all(new_json.to_string().as_bytes()).await?;
(*guard).flush().await?;
drop(guard);
// TODO check if URLs changed between old and new JSON
Ok(())
}
async fn get_channels(
&self,
user: &crate::indieauth::User,
) -> Result<Vec<super::MicropubChannel>> {
todo!()
}
async fn read_feed_with_limit<'a>(
&self,
url: &'a str,
after: &'a Option<String>,
limit: usize,
user: &'a Option<String>,
) -> Result<Option<serde_json::Value>> {
todo!()
}
async fn delete_post<'a>(&self, url: &'a str) -> Result<()> {
todo!()
}
async fn get_setting<'a>(&self, setting: &'a str, user: &'a str) -> Result<String> {
let url = http_types::Url::parse(user).expect("Couldn't parse a URL");
let mut path = relative_path::RelativePathBuf::new();
path.push(url.origin().ascii_serialization());
path.push("settings");
let path = path.to_path(&self.root_dir);
let lock = get_lockable_file(File::open(path).await?).await;
let guard = lock.read()?;
let mut content = String::new();
(&mut &*guard).read_to_string(&mut content).await?;
drop(guard);
let settings: HashMap<String, String> = serde_json::from_str(&content)?;
// XXX consider returning string slices instead of cloning a string every time
// it might come with a performance hit and/or memory usage inflation
settings.get(setting)
.map(|s| s.clone())
.ok_or_else(|| StorageError::new(ErrorKind::Backend, "Setting not set"))
}
async fn set_setting<'a>(&self, setting: &'a str, user: &'a str, value: &'a str) -> Result<()> {
let url = http_types::Url::parse(user).expect("Couldn't parse a URL");
let mut path = relative_path::RelativePathBuf::new();
path.push(url.origin().ascii_serialization());
path.push("settings");
let path = path.to_path(&self.root_dir);
let parent = path.parent().unwrap().to_owned();
if !spawn_blocking(move || parent.is_dir()).await {
async_std::fs::create_dir_all(path.parent().unwrap()).await?;
}
let file = OpenOptions::new()
.write(true)
.read(true)
.truncate(false)
.create(true)
.open(&path).await?;
let mut lock = get_lockable_file(file).await;
let mut guard = lock.write()?;
let mut content = String::new();
guard.read_to_string(&mut content).await?;
let mut settings: HashMap<String, String> = if content.len() == 0 {
HashMap::default()
} else {
serde_json::from_str(&content)?
};
settings.insert(setting.to_string(), value.to_string());
guard.seek(std::io::SeekFrom::Start(0)).await?;
guard.set_len(0).await?;
guard.write_all(serde_json::to_string(&settings)?.as_bytes()).await?;
Ok(())
}
}