Source code
Revision control
Copy as Markdown
Other Tools
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use crate::error::*;
use crate::schema;
use interrupt_support::{SqlInterruptHandle, SqlInterruptScope};
use parking_lot::Mutex;
use rusqlite::types::{FromSql, ToSql};
use rusqlite::Connection;
use rusqlite::OpenFlags;
use sql_support::open_database::open_database_with_flags;
use sql_support::ConnExt;
use std::ops::Deref;
use std::path::{Path, PathBuf};
use std::sync::Arc;
use url::Url;
/// A `StorageDb` wraps a read-write SQLite connection, and handles schema
/// migrations and recovering from database file corruption. It can be used
/// anywhere a `rusqlite::Connection` is expected, thanks to its `Deref{Mut}`
/// implementations.
///
/// We only support a single writer connection - so that's the only thing we
/// store. It's still a bit overkill, but there's only so many yaks in a day.
pub enum WebExtStorageDb {
Open(Connection),
Closed,
}
pub struct StorageDb {
pub writer: WebExtStorageDb,
interrupt_handle: Arc<SqlInterruptHandle>,
}
impl StorageDb {
/// Create a new, or fetch an already open, StorageDb backed by a file on disk.
pub fn new(db_path: impl AsRef<Path>) -> Result<Self> {
let db_path = normalize_path(db_path)?;
Self::new_named(db_path)
}
/// Create a new, or fetch an already open, memory-based StorageDb. You must
/// provide a name, but you are still able to have a single writer and many
/// reader connections to the same memory DB open.
#[cfg(test)]
pub fn new_memory(db_path: &str) -> Result<Self> {
let name = PathBuf::from(format!("file:{}?mode=memory&cache=shared", db_path));
Self::new_named(name)
}
fn new_named(db_path: PathBuf) -> Result<Self> {
// We always create the read-write connection for an initial open so
// we can create the schema and/or do version upgrades.
let flags = OpenFlags::SQLITE_OPEN_NO_MUTEX
| OpenFlags::SQLITE_OPEN_URI
| OpenFlags::SQLITE_OPEN_CREATE
| OpenFlags::SQLITE_OPEN_READ_WRITE;
let conn = open_database_with_flags(db_path, flags, &schema::WebExtMigrationLogin)?;
Ok(Self {
interrupt_handle: Arc::new(SqlInterruptHandle::new(&conn)),
writer: WebExtStorageDb::Open(conn),
})
}
pub fn interrupt_handle(&self) -> Arc<SqlInterruptHandle> {
Arc::clone(&self.interrupt_handle)
}
#[allow(dead_code)]
pub fn begin_interrupt_scope(&self) -> Result<SqlInterruptScope> {
Ok(self.interrupt_handle.begin_interrupt_scope()?)
}
/// Closes the database connection. If there are any unfinalized prepared
/// statements on the connection, `close` will fail and the `StorageDb` will
/// remain open and the connection will be leaked - we used to return the
/// underlying connection so the caller can retry but (a) that's very tricky
/// in an Arc<Mutex<>> world and (b) we never actually took advantage of
/// that retry capability.
pub fn close(&mut self) -> Result<()> {
let conn = match std::mem::replace(&mut self.writer, WebExtStorageDb::Closed) {
WebExtStorageDb::Open(conn) => conn,
WebExtStorageDb::Closed => return Ok(()),
};
conn.close().map_err(|(_, y)| Error::SqlError(y))
}
pub(crate) fn get_connection(&self) -> Result<&Connection> {
let db = &self.writer;
match db {
WebExtStorageDb::Open(y) => Ok(y),
WebExtStorageDb::Closed => Err(Error::DatabaseConnectionClosed),
}
}
}
// We almost exclusively use this ThreadSafeStorageDb
pub struct ThreadSafeStorageDb {
db: Mutex<StorageDb>,
// This "outer" interrupt_handle not protected by the mutex means
// consumers can interrupt us when the mutex is held - which it always will
// be if we are doing anything interruptible!
interrupt_handle: Arc<SqlInterruptHandle>,
}
impl ThreadSafeStorageDb {
pub fn new(db: StorageDb) -> Self {
Self {
interrupt_handle: db.interrupt_handle(),
db: Mutex::new(db),
}
}
pub fn interrupt_handle(&self) -> Arc<SqlInterruptHandle> {
Arc::clone(&self.interrupt_handle)
}
pub fn begin_interrupt_scope(&self) -> Result<SqlInterruptScope> {
Ok(self.interrupt_handle.begin_interrupt_scope()?)
}
pub fn into_inner(self) -> StorageDb {
self.db.into_inner()
}
}
// Deref to a Mutex<StorageDb>, which is how we will use ThreadSafeStorageDb most of the time
impl Deref for ThreadSafeStorageDb {
type Target = Mutex<StorageDb>;
#[inline]
fn deref(&self) -> &Mutex<StorageDb> {
&self.db
}
}
// Also implement AsRef<SqlInterruptHandle> so that we can interrupt this at shutdown
impl AsRef<SqlInterruptHandle> for ThreadSafeStorageDb {
fn as_ref(&self) -> &SqlInterruptHandle {
&self.interrupt_handle
}
}
pub(crate) mod sql_fns {
use rusqlite::{functions::Context, Result};
use sync_guid::Guid as SyncGuid;
#[inline(never)]
pub fn generate_guid(_ctx: &Context<'_>) -> Result<SyncGuid> {
Ok(SyncGuid::random())
}
}
// These should be somewhere else...
pub fn put_meta(db: &Connection, key: &str, value: &dyn ToSql) -> Result<()> {
db.conn().execute_cached(
"REPLACE INTO meta (key, value) VALUES (:key, :value)",
rusqlite::named_params! { ":key": key, ":value": value },
)?;
Ok(())
}
pub fn get_meta<T: FromSql>(db: &Connection, key: &str) -> Result<Option<T>> {
let res = db.conn().try_query_one(
"SELECT value FROM meta WHERE key = :key",
&[(":key", &key)],
true,
)?;
Ok(res)
}
pub fn delete_meta(db: &Connection, key: &str) -> Result<()> {
db.conn()
.execute_cached("DELETE FROM meta WHERE key = :key", &[(":key", &key)])?;
Ok(())
}
// Utilities for working with paths.
// (From places_utils - ideally these would be shared, but the use of
// ErrorKind values makes that non-trivial.
/// `Path` is basically just a `str` with no validation, and so in practice it
/// could contain a file URL. Rusqlite takes advantage of this a bit, and says
/// `AsRef<Path>` but really means "anything sqlite can take as an argument".
///
/// Swift loves using file urls (the only support it has for file manipulation
/// is through file urls), so it's handy to support them if possible.
fn unurl_path(p: impl AsRef<Path>) -> PathBuf {
p.as_ref()
.to_str()
.and_then(|s| Url::parse(s).ok())
.and_then(|u| {
if u.scheme() == "file" {
u.to_file_path().ok()
} else {
None
}
})
.unwrap_or_else(|| p.as_ref().to_owned())
}
/// If `p` is a file URL, return it, otherwise try and make it one.
///
/// Errors if `p` is a relative non-url path, or if it's a URL path
/// that's isn't a `file:` URL.
#[allow(dead_code)]
pub fn ensure_url_path(p: impl AsRef<Path>) -> Result<Url> {
if let Some(u) = p.as_ref().to_str().and_then(|s| Url::parse(s).ok()) {
if u.scheme() == "file" {
Ok(u)
} else {
Err(Error::IllegalDatabasePath(p.as_ref().to_owned()))
}
} else {
let p = p.as_ref();
let u = Url::from_file_path(p).map_err(|_| Error::IllegalDatabasePath(p.to_owned()))?;
Ok(u)
}
}
/// As best as possible, convert `p` into an absolute path, resolving
/// all symlinks along the way.
///
/// If `p` is a file url, it's converted to a path before this.
fn normalize_path(p: impl AsRef<Path>) -> Result<PathBuf> {
let path = unurl_path(p);
if let Ok(canonical) = path.canonicalize() {
return Ok(canonical);
}
// It probably doesn't exist yet. This is an error, although it seems to
// work on some systems.
//
// We resolve this by trying to canonicalize the parent directory, and
// appending the requested file name onto that. If we can't canonicalize
// the parent, we return an error.
//
// Also, we return errors if the path ends in "..", if there is no
// parent directory, etc.
let file_name = path
.file_name()
.ok_or_else(|| Error::IllegalDatabasePath(path.clone()))?;
let parent = path
.parent()
.ok_or_else(|| Error::IllegalDatabasePath(path.clone()))?;
let mut canonical = parent.canonicalize()?;
canonical.push(file_name);
Ok(canonical)
}
// Helpers for tests
#[cfg(test)]
pub mod test {
use super::*;
use std::sync::atomic::{AtomicUsize, Ordering};
// A helper for our tests to get their own memory Api.
static ATOMIC_COUNTER: AtomicUsize = AtomicUsize::new(0);
pub fn new_mem_db() -> StorageDb {
let _ = env_logger::try_init();
let counter = ATOMIC_COUNTER.fetch_add(1, Ordering::Relaxed);
StorageDb::new_memory(&format!("test-api-{}", counter)).expect("should get an API")
}
pub fn new_mem_thread_safe_storage_db() -> Arc<ThreadSafeStorageDb> {
Arc::new(ThreadSafeStorageDb::new(new_mem_db()))
}
}
#[cfg(test)]
mod tests {
use super::test::*;
use super::*;
// Sanity check that we can create a database.
#[test]
fn test_open() {
new_mem_db();
// XXX - should we check anything else? Seems a bit pointless, but if
// we move the meta functions away from here then it's better than
// nothing.
}
#[test]
fn test_meta() -> Result<()> {
let db = new_mem_db();
let conn = &db.get_connection()?;
assert_eq!(get_meta::<String>(conn, "foo")?, None);
put_meta(conn, "foo", &"bar".to_string())?;
assert_eq!(get_meta(conn, "foo")?, Some("bar".to_string()));
delete_meta(conn, "foo")?;
assert_eq!(get_meta::<String>(conn, "foo")?, None);
Ok(())
}
}