where
C: Default + Append + serde::Serialize + serde::de::DeserializeOwned,
{
- /// Creates a new store from a [`File`].
+ /// Create a new [`Store`] file in write-only mode; error if the file exists.
///
- /// The file must have been opened with read and write permissions.
+ /// `magic` is the prefixed bytes to write to the new file. This will be checked when opening
+ /// the `Store` in the future with [`open`].
///
- /// `magic` is the expected prefixed bytes of the file. If this does not match, an error will be
- /// returned.
+ /// [`open`]: Store::open
+ pub fn create_new<P>(magic: &'a [u8], file_path: P) -> Result<Self, FileError>
+ where
+ P: AsRef<Path>,
+ {
+ if file_path.as_ref().exists() {
+ // `io::Error` is used instead of a variant on `FileError` because there is already a
+ // nightly-only `File::create_new` method
+ return Err(FileError::Io(io::Error::new(
+ io::ErrorKind::Other,
+ "file already exists",
+ )));
+ }
+ let mut f = OpenOptions::new()
+ .create(true)
+ .read(true)
+ .write(true)
+ .open(file_path)?;
+ f.write_all(magic)?;
+ Ok(Self {
+ magic,
+ db_file: f,
+ marker: Default::default(),
+ })
+ }
+
+ /// Open an existing [`Store`].
+ ///
+ /// Use [`create_new`] to create a new `Store`.
///
- /// [`File`]: std::fs::File
- pub fn new(magic: &'a [u8], mut db_file: File) -> Result<Self, FileError> {
- db_file.rewind()?;
+ /// # Errors
+ ///
+ /// If the prefixed bytes of the opened file does not match the provided `magic`, the
+ /// [`FileError::InvalidMagicBytes`] error variant will be returned.
+ ///
+ /// [`create_new`]: Store::create_new
+ pub fn open<P>(magic: &'a [u8], file_path: P) -> Result<Self, FileError>
+ where
+ P: AsRef<Path>,
+ {
+ let mut f = OpenOptions::new().read(true).write(true).open(file_path)?;
let mut magic_buf = vec![0_u8; magic.len()];
- db_file.read_exact(magic_buf.as_mut())?;
-
+ f.read_exact(&mut magic_buf)?;
if magic_buf != magic {
return Err(FileError::InvalidMagicBytes {
got: magic_buf,
Ok(Self {
magic,
- db_file,
+ db_file: f,
marker: Default::default(),
})
}
- /// Creates or loads a store from `db_path`.
- ///
- /// If no file exists there, it will be created.
+ /// Attempt to open existing [`Store`] file; create it if the file is non-existant.
///
- /// Refer to [`new`] for documentation on the `magic` input.
+ /// Internally, this calls either [`open`] or [`create_new`].
///
- /// [`new`]: Self::new
- pub fn new_from_path<P>(magic: &'a [u8], db_path: P) -> Result<Self, FileError>
+ /// [`open`]: Store::open
+ /// [`create_new`]: Store::create_new
+ pub fn open_or_create_new<P>(magic: &'a [u8], file_path: P) -> Result<Self, FileError>
where
P: AsRef<Path>,
{
- let already_exists = db_path.as_ref().exists();
-
- let mut db_file = OpenOptions::new()
- .read(true)
- .write(true)
- .create(true)
- .open(db_path)?;
-
- if !already_exists {
- db_file.write_all(magic)?;
+ if file_path.as_ref().exists() {
+ Self::open(magic, file_path)
+ } else {
+ Self::create_new(magic, file_path)
}
-
- Self::new(magic, db_file)
}
/// Iterates over the stored changeset from first to last, changing the seek position at each
let mut file = NamedTempFile::new().unwrap();
file.write_all(&TEST_MAGIC_BYTES).expect("should write");
- let mut db = Store::<TestChangeSet>::new(&TEST_MAGIC_BYTES, file.reopen().unwrap())
- .expect("must open");
+ let mut db =
+ Store::<TestChangeSet>::open(&TEST_MAGIC_BYTES, file.path()).expect("must open");
assert!(db.is_empty().expect("must read"));
db.write_changes(&vec!["hello".to_string(), "world".to_string()])
.expect("must write");
file.write_all(&TEST_MAGIC_BYTES[..TEST_MAGIC_BYTES_LEN - 1])
.expect("should write");
- match Store::<TestChangeSet>::new(&TEST_MAGIC_BYTES, file.reopen().unwrap()) {
+ match Store::<TestChangeSet>::open(&TEST_MAGIC_BYTES, file.path()) {
Err(FileError::Io(e)) => assert_eq!(e.kind(), std::io::ErrorKind::UnexpectedEof),
unexpected => panic!("unexpected result: {:?}", unexpected),
};
file.write_all(invalid_magic_bytes.as_bytes())
.expect("should write");
- match Store::<TestChangeSet>::new(&TEST_MAGIC_BYTES, file.reopen().unwrap()) {
+ match Store::<TestChangeSet>::open(&TEST_MAGIC_BYTES, file.path()) {
Err(FileError::InvalidMagicBytes { got, .. }) => {
assert_eq!(got, invalid_magic_bytes.as_bytes())
}
let mut file = NamedTempFile::new().unwrap();
file.write_all(&data).expect("should write");
- let mut store = Store::<TestChangeSet>::new(&TEST_MAGIC_BYTES, file.reopen().unwrap())
- .expect("should open");
+ let mut store =
+ Store::<TestChangeSet>::open(&TEST_MAGIC_BYTES, file.path()).expect("should open");
match store.iter_changesets().next() {
Some(Err(IterError::Bincode(_))) => {}
unexpected_res => panic!("unexpected result: {:?}", unexpected_res),
projects / bdk / commitdiff