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// Copyright 2018-2019 Mozilla
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use
// this file except in compliance with the License. You may obtain a copy of the
// Unless required by applicable law or agreed to in writing, software distributed
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
// specific language governing permissions and limitations under the License.
use std::fmt;
use arrayref::array_ref;
use bincode::{deserialize, serialize, serialized_size};
use ordered_float::OrderedFloat;
use uuid::{Bytes, Uuid};
use crate::error::DataError;
/// We define a set of types, associated with simple integers, to annotate values stored
/// in LMDB. This is to avoid an accidental 'cast' from a value of one type to another.
/// For this reason we don't simply use `deserialize` from the `bincode` crate.
#[repr(u8)]
#[derive(Debug, PartialEq, Eq)]
pub enum Type {
Bool = 1,
U64 = 2,
I64 = 3,
F64 = 4,
Instant = 5, // Millisecond-precision timestamp.
Uuid = 6,
Str = 7,
Json = 8,
Blob = 9,
}
impl Type {
pub fn from_tag(tag: u8) -> Result<Type, DataError> {
#![allow(clippy::unnecessary_lazy_evaluations)]
Type::from_primitive(tag).ok_or_else(|| DataError::UnknownType(tag))
}
#[allow(clippy::wrong_self_convention)]
pub fn to_tag(self) -> u8 {
self as u8
}
fn from_primitive(p: u8) -> Option<Type> {
match p {
1 => Some(Type::Bool),
2 => Some(Type::U64),
3 => Some(Type::I64),
4 => Some(Type::F64),
5 => Some(Type::Instant),
6 => Some(Type::Uuid),
7 => Some(Type::Str),
8 => Some(Type::Json),
9 => Some(Type::Blob),
_ => None,
}
}
}
impl fmt::Display for Type {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
f.write_str(match *self {
Type::Bool => "bool",
Type::U64 => "u64",
Type::I64 => "i64",
Type::F64 => "f64",
Type::Instant => "instant",
Type::Uuid => "uuid",
Type::Str => "str",
Type::Json => "json",
Type::Blob => "blob",
})
}
}
#[derive(Debug, Eq, PartialEq)]
pub enum Value<'v> {
Bool(bool),
U64(u64),
I64(i64),
F64(OrderedFloat<f64>),
Instant(i64), // Millisecond-precision timestamp.
Uuid(&'v Bytes),
Str(&'v str),
Json(&'v str),
Blob(&'v [u8]),
}
#[derive(Clone, Debug, PartialEq)]
pub enum OwnedValue {
Bool(bool),
U64(u64),
I64(i64),
F64(f64),
Instant(i64), // Millisecond-precision timestamp.
Uuid(Uuid),
Str(String),
Json(String), // TODO
Blob(Vec<u8>),
}
fn uuid(bytes: &[u8]) -> Result<Value, DataError> {
if bytes.len() == 16 {
Ok(Value::Uuid(array_ref![bytes, 0, 16]))
} else {
Err(DataError::InvalidUuid)
}
}
impl<'v> Value<'v> {
pub fn from_tagged_slice(slice: &'v [u8]) -> Result<Value<'v>, DataError> {
let (tag, data) = slice.split_first().ok_or(DataError::Empty)?;
let t = Type::from_tag(*tag)?;
Value::from_type_and_data(t, data)
}
fn from_type_and_data(t: Type, data: &'v [u8]) -> Result<Value<'v>, DataError> {
if t == Type::Uuid {
return deserialize(data)
.map_err(|e| DataError::DecodingError {
value_type: t,
err: e,
})
.map(uuid)?;
}
match t {
Type::Bool => deserialize(data).map(Value::Bool),
Type::U64 => deserialize(data).map(Value::U64),
Type::I64 => deserialize(data).map(Value::I64),
Type::F64 => deserialize(data).map(OrderedFloat).map(Value::F64),
Type::Instant => deserialize(data).map(Value::Instant),
Type::Str => deserialize(data).map(Value::Str),
Type::Json => deserialize(data).map(Value::Json),
Type::Blob => deserialize(data).map(Value::Blob),
Type::Uuid => {
// Processed above to avoid verbose duplication of error transforms.
unreachable!()
}
}
.map_err(|e| DataError::DecodingError {
value_type: t,
err: e,
})
}
pub fn to_bytes(&self) -> Result<Vec<u8>, DataError> {
match self {
Value::Bool(v) => serialize(&(Type::Bool.to_tag(), *v)),
Value::U64(v) => serialize(&(Type::U64.to_tag(), *v)),
Value::I64(v) => serialize(&(Type::I64.to_tag(), *v)),
Value::F64(v) => serialize(&(Type::F64.to_tag(), v.0)),
Value::Instant(v) => serialize(&(Type::Instant.to_tag(), *v)),
Value::Str(v) => serialize(&(Type::Str.to_tag(), v)),
Value::Json(v) => serialize(&(Type::Json.to_tag(), v)),
Value::Blob(v) => serialize(&(Type::Blob.to_tag(), v)),
Value::Uuid(v) => serialize(&(Type::Uuid.to_tag(), v)),
}
.map_err(DataError::EncodingError)
}
pub fn serialized_size(&self) -> Result<u64, DataError> {
match self {
Value::Bool(v) => serialized_size(&(Type::Bool.to_tag(), *v)),
Value::U64(v) => serialized_size(&(Type::U64.to_tag(), *v)),
Value::I64(v) => serialized_size(&(Type::I64.to_tag(), *v)),
Value::F64(v) => serialized_size(&(Type::F64.to_tag(), v.0)),
Value::Instant(v) => serialized_size(&(Type::Instant.to_tag(), *v)),
Value::Str(v) => serialized_size(&(Type::Str.to_tag(), v)),
Value::Json(v) => serialized_size(&(Type::Json.to_tag(), v)),
Value::Blob(v) => serialized_size(&(Type::Blob.to_tag(), v)),
Value::Uuid(v) => serialized_size(&(Type::Uuid.to_tag(), v)),
}
.map_err(DataError::EncodingError)
}
}
impl<'v> From<&'v Value<'v>> for OwnedValue {
fn from(value: &Value) -> OwnedValue {
match value {
Value::Bool(v) => OwnedValue::Bool(*v),
Value::U64(v) => OwnedValue::U64(*v),
Value::I64(v) => OwnedValue::I64(*v),
Value::F64(v) => OwnedValue::F64(**v),
Value::Instant(v) => OwnedValue::Instant(*v),
Value::Uuid(v) => OwnedValue::Uuid(Uuid::from_bytes(**v)),
Value::Str(v) => OwnedValue::Str((*v).to_string()),
Value::Json(v) => OwnedValue::Json((*v).to_string()),
Value::Blob(v) => OwnedValue::Blob(v.to_vec()),
}
}
}
impl<'v> From<&'v OwnedValue> for Value<'v> {
fn from(value: &OwnedValue) -> Value {
match value {
OwnedValue::Bool(v) => Value::Bool(*v),
OwnedValue::U64(v) => Value::U64(*v),
OwnedValue::I64(v) => Value::I64(*v),
OwnedValue::F64(v) => Value::F64(OrderedFloat::from(*v)),
OwnedValue::Instant(v) => Value::Instant(*v),
OwnedValue::Uuid(v) => Value::Uuid(v.as_bytes()),
OwnedValue::Str(v) => Value::Str(v),
OwnedValue::Json(v) => Value::Json(v),
OwnedValue::Blob(v) => Value::Blob(v),
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_value_serialized_size() {
// | Value enum | tag: 1 byte | value_payload |
// |----------------------------------------------------------|
// | I64 | 1 | 8 |
// | U64 | 1 | 8 |
// | Bool | 1 | 1 |
// | Instant | 1 | 8 |
// | F64 | 1 | 8 |
// | Uuid | 1 | 16 |
// | Str/Blob/Json | 1 |(8: len + sizeof(payload))|
assert_eq!(Value::I64(-1000).serialized_size().unwrap(), 9);
assert_eq!(Value::U64(1000u64).serialized_size().unwrap(), 9);
assert_eq!(Value::Bool(true).serialized_size().unwrap(), 2);
assert_eq!(
Value::Instant(1_558_020_865_224).serialized_size().unwrap(),
9
);
assert_eq!(
Value::F64(OrderedFloat(10000.1)).serialized_size().unwrap(),
9
);
assert_eq!(Value::Str("hello!").serialized_size().unwrap(), 15);
assert_eq!(Value::Str("¡Hola").serialized_size().unwrap(), 15);
assert_eq!(Value::Blob(b"hello!").serialized_size().unwrap(), 15);
assert_eq!(
uuid(b"\x9f\xe2\xc4\xe9\x3f\x65\x4f\xdb\xb2\x4c\x02\xb1\x52\x59\x71\x6c")
.unwrap()
.serialized_size()
.unwrap(),
17
);
}
}