This crate is an implementation of basic MySql protocol primitives.
This crate:
- defines basic MySql constants;
- implements necessary functionality for MySql
cached_sha2_password,mysql_native_passwordand legacy authentication plugins; - implements helper traits for MySql protocol IO;
- implements support of named parameters for prepared statements;
- implements parsers for a subset of MySql protocol packets (including binlog packets);
- defines rust representation of MySql protocol values and rows;
- implements conversion between MySql values and rust types, between MySql rows and tuples of rust types.
- implements FromRow and FromValue derive macros
Crate offers conversion from/to MySql values for following types (please see MySql documentation
on supported ranges for numeric types). Following table refers to MySql protocol types
(see Value struct) and not to MySql column types. Please see MySql documentation for
column and protocol type correspondence:
| Type | Notes |
|---|---|
{i,u}8..{i,u}128, {i,u}size |
MySql int/uint will be converted, bytes will be parsed.{i,u}128 is greater than supported by MySql integer types but it'll be serialized anyway (as decimal bytes string). |
f32 |
MySql float will be converted to f32, bytes will be parsed as f32.f32 to avoid precision loss (see #17) |
f64 |
MySql float and double will be converted to f64, bytes will be parsed as f64. |
bool |
MySql int {0, 1} or bytes {"0x30", "0x31"} |
Vec<u8> |
MySql bytes |
String |
MySql bytes parsed as utf8 |
Duration (std and time) |
MySql time or bytes parsed as MySql time string |
[time::PrimitiveDateTime] (v0.2.x) |
MySql date time or bytes parsed as MySql date time string ( |
[time::Date] (v0.2.x) |
MySql date or bytes parsed as MySql date string ( |
[time::Time] (v0.2.x) |
MySql time or bytes parsed as MySql time string ( |
[time::Duration] (v0.2.x) |
MySql time or bytes parsed as MySql time string |
[time::PrimitiveDateTime] (v0.3.x) |
MySql date time or bytes parsed as MySql date time string ( |
[time::Date] (v0.3.x) |
MySql date or bytes parsed as MySql date string ( |
[time::Time] (v0.3.x) |
MySql time or bytes parsed as MySql time string ( |
[time::Duration] (v0.3.x) |
MySql time or bytes parsed as MySql time string |
[chrono::NaiveTime] |
MySql date or bytes parsed as MySql date string |
[chrono::NaiveDate] |
MySql date or bytes parsed as MySql date string |
[chrono::NaiveDateTime] |
MySql date or bytes parsed as MySql date string |
[uuid::Uuid] |
MySql bytes parsed using Uuid::from_slice |
[serde_json::Value] |
MySql bytes parsed using serde_json::from_str |
mysql_common::Deserialized<T : DeserializeOwned> |
MySql bytes parsed using serde_json::from_str |
Option<T: FromValue> |
Must be used for nullable columns to avoid errors |
[decimal::Decimal] |
MySql int, uint or bytes parsed using Decimal::from_str.DECIMAL type. |
[bigdecimal::BigDecimal] (v0.2.x) |
MySql int, uint, floats or bytes parsed using BigDecimal::parse_bytes.DECIMAL type but it'll be serialized anyway. |
[bigdecimal::BigDecimal] (v0.3.x) |
MySql int, uint, floats or bytes parsed using BigDecimal::parse_bytes.DECIMAL type but it'll be serialized anyway. |
[bigdecimal::BigDecimal] (v0.4.x) |
MySql int, uint, floats or bytes parsed using BigDecimal::parse_bytes.DECIMAL type but it'll be serialized anyway. |
num_bigint::{BigInt, BigUint} |
MySql int, uint or bytes parsed using _::parse_bytes. |
Also crate provides from-row convertion for the following list of types (see FromRow trait):
| Type | Notes |
|---|---|
Row |
Trivial conversion for Row itself. |
T: FromValue |
For rows with a single column. |
(T1: FromValue [, ..., T12: FromValue]) |
Row to a tuple of arity 1-12. |
[frunk::hlist::HList] types |
Usefull to overcome tuple arity limitation |
| Feature | Description | Default |
|---|---|---|
bigdecimal02 |
Enables bigdecimal v0.2.x types support |
🔴 |
bigdecimal03 |
Enables bigdecimal v0.3.x types support |
🔴 |
bigdecimal |
Enables bigdecimal v0.4.x types support |
🟢 |
chrono |
Enables chrono types support |
🔴 |
rust_decimal |
Enables rust_decimal types support |
🟢 |
time02 |
Enables time v0.2.x types support |
🔴 |
time |
Enables time v0.3.x types support |
🟢 |
frunk |
Enables FromRow for frunk::Hlist! types |
🟢 |
derive |
Enables FromValue and FromRow derive macros |
🟢 |
binlog |
Binlog-related functionality | 🟢 |
Supported derivations:
- for enum – you should carefully read the corresponding section of MySql documentation.
- for newtypes (see New Type Idiom) – given that the wrapped type itself satisfies
FromValue.
#[mysql(crate_name = "some_name")]– overrides an attempt to guess a crate that provides required traits#[mysql(rename_all = ...)]– rename all the variants according to the given case convention. The possible values are "lowercase", "UPPERCASE", "PascalCase", "camelCase", "snake_case", "SCREAMING_SNAKE_CASE", "kebab-case", "SCREAMING-KEBAB-CASE"#[mysql(is_integer)]– tells derive macro that the value is an integer rather than MySql ENUM. Macro won't warn if variants are sparse or greater than u16 and will not try to parse textual representation.#[mysql(is_string)]– tells derive macro that the value is a string rather than MySql ENUM. Macro won't warn if variants are sparse or greater than u16 and will not try to parse integer representation.
Given ENUM('x-small', 'small', 'medium', 'large', 'x-large') on MySql side:
fn main() {
/// Note: the `crate_name` attribute should not be necessary.
#[derive(FromValue)]
#[mysql(rename_all = "kebab-case", crate_name = "mysql_common")]
#[repr(u8)]
enum Size {
XSmall = 1,
Small,
Medium,
Large,
XLarge,
}
fn assert_from_row_works(x: Row) -> Size {
from_row(x)
}
}It is expected, that wrapper value satisfies FromValue or deserialize_with is given.
Also note, that to support FromRow the wrapped value must satisfy Into<Value> or
serialize_with must be given.
#[mysql(crate_name = "some_name")]– overrides an attempt to guess a crate to import types from#[mysql(bound = "Foo: Bar, Baz: Quux")]– use the following additional bounds#[mysql(deserialize_with = "some::path")]– use the following function to deserialize the wrapped value. Expected signature isfn (Value) -> Result<Wrapped, FromValueError>.#[mysql(serialize_with = "some::path")]– use the following function to serialize the wrapped value. Expected signature isfn (Wrapped) -> Value.
/// Trivial example
#[derive(FromValue)]
struct Inch(i32);
/// Example of a {serialize|deserialize}_with.
#[derive(FromValue)]
#[mysql(deserialize_with = "neg_de", serialize_with = "neg_ser")]
struct Neg(i64);
/// Wrapped generic. Bounds are inferred.
#[derive(FromValue)]
struct Foo<T>(Option<T>);
/// Example of additional bounds.
#[derive(FromValue)]
#[mysql(bound = "'b: 'a, T: 'a, U: From<String>, V: From<u64>")]
struct Bar<'a, 'b, const N: usize, T, U, V>(ComplexTypeToWrap<'a, 'b, N, T, U, V>);
fn assert_from_row_works<'a, 'b, const N: usize, T, U, V>(x: Row) -> (Inch, Neg, Foo<u8>, Bar<'a, 'b, N, T, U, V>)
where 'b: 'a, T: 'a, U: From<String>, V: From<u64>,
{
from_row(x)
}
// test boilerplate..
/// Dummy complex type with additional bounds on FromValue impl.
struct ComplexTypeToWrap<'a, 'b, const N: usize, T, U, V>([(&'a T, &'b U, V); N]);
struct FakeIr;
impl TryFrom<Value> for FakeIr {
// ...
}
impl<'a, 'b: 'a, const N: usize, T: 'a, U: From<String>, V: From<u64>> From<FakeIr> for ComplexTypeToWrap<'a, 'b, N, T, U, V> {
// ...
}
impl From<FakeIr> for Value {
// ...
}
impl<'a, 'b: 'a, const N: usize, T: 'a, U: From<String>, V: From<u64>> FromValue for ComplexTypeToWrap<'a, 'b, N, T, U, V> {
type Intermediate = FakeIr;
}
fn neg_de(v: Value) -> Result<i64, FromValueError> {
match v {
Value::Int(x) => Ok(-x),
Value::UInt(x) => Ok(-(x as i64)),
x => Err(FromValueError(x)),
}
}
fn neg_ser(x: i64) -> Value {
Value::Int(-x)
}Also defines some constants on the struct:
const TABLE_NAME: &str– iftable_nameis givenconst {}_FIELD: &str– for each struct field ({}is a SCREAMING_SNAKE_CASE representation of a struct field name (not a column name))
Supported derivations:
- for a struct with named fields – field name will be used as a column name to search for a value
#[mysql(crate_name = "some_name")]– overrides an attempt to guess a crate that provides required traits#[mysql(rename_all = ...)]– rename all column names according to the given case convention. The possible values are "lowercase", "UPPERCASE", "PascalCase", "camelCase", "snake_case", "SCREAMING_SNAKE_CASE", "kebab-case", "SCREAMING-KEBAB-CASE"#[mysql(table_name = "some_name")]– definespub const TABLE_NAME: &stron the struct
#[mysql(rename = "some_name")]– overrides column name of a field#[mysql(json)]- column will be interpreted as a JSON string containing a value of a field type
/// Note: the `crate_name` attribute should not be necessary.
#[derive(Debug, PartialEq, Eq, FromRow)]
#[mysql(table_name = "Foos", crate_name = "mysql_common")]
struct Foo {
id: u64,
#[mysql(json, rename = "def")]
definition: Bar,
child: Option<u64>,
}
#[derive(Debug, serde::Deserialize, PartialEq, Eq)]
enum Bar {
Left,
Right,
}
/// Returns the following row:
///
/// ```
/// +----+-----------+-------+
/// | id | def | child |
/// +----+-----------+-------+
/// | 42 | '"Right"' | NULL |
/// +----+-----------+-------+
/// ```
fn get_row() -> Row {
// ...
}
assert_eq!(Foo::TABLE_NAME, "Foos");
assert_eq!(Foo::ID_FIELD, "id");
assert_eq!(Foo::DEFINITION_FIELD, "def");
assert_eq!(Foo::CHILD_FIELD, "child");
let foo = from_row::<Foo>(get_row());
assert_eq!(foo, Foo { id: 42, definition: Bar::Right, child: None });Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT) at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.