Add support for bstr::BString (under the bstr feature flag)

This allows queries to convert between BString and SQL data types.

Cargo.lock

@@ -2206,6 +2206,7 @@ dependencies = [
  "bigdecimal",
  "bit-vec",
  "bitflags",
+ "bstr",
  "byteorder",
  "bytes",
  "chrono",

Cargo.toml

@@ -89,6 +89,7 @@ uuid = [ "sqlx-core/uuid", "sqlx-macros/uuid" ]
 json = [ "sqlx-core/json", "sqlx-macros/json" ]
 time = [ "sqlx-core/time", "sqlx-macros/time" ]
 bit-vec = [ "sqlx-core/bit-vec", "sqlx-macros/bit-vec"]
+bstr = [ "sqlx-core/bstr" ]
 
 [dependencies]
 sqlx-core = { version = "=0.4.0", path = "sqlx-core", default-features = false }

README.md

@@ -152,6 +152,8 @@ sqlx = { version = "0.4.0", features = [ "runtime-async-std-native-tls" ] }
 
 -   `time`: Add support for date and time types from `time` crate (alternative to `chrono`, prefered by `query!` macro, if both enabled)
 
+-   `bstr`: Add support for `bstr::BString`.
+
 -   `bigdecimal`: Add support for `NUMERIC` using the `bigdecimal` crate.
 
 -   `decimal`: Add support for `NUMERIC` using the `rust_decimal` crate.

sqlx-core/Cargo.toml

@@ -107,3 +107,4 @@ webpki-roots = { version = "0.20.0", optional = true }
 whoami = "0.9.0"
 stringprep = "0.1.2"
 lru-cache = "0.1.2"
+bstr = { version = "0.2.14", default-features = false, features = [ "std" ], optional = true }

sqlx-core/src/types/bstr.rs

@@ -0,0 +1,42 @@
+/// Conversions between `bstr` types and SQL types.
+use crate::database::{Database, HasArguments, HasValueRef};
+use crate::decode::Decode;
+use crate::encode::{Encode, IsNull};
+use crate::error::BoxDynError;
+use crate::types::Type;
+
+pub use bstr::{BString, ByteSlice};
+
+impl<DB> Type<DB> for BString
+where
+    DB: Database,
+    [u8]: Type<DB>,
+{
+    fn type_info() -> DB::TypeInfo {
+        <&[u8] as Type<DB>>::type_info()
+    }
+
+    fn compatible(ty: &DB::TypeInfo) -> bool {
+        <&[u8] as Type<DB>>::compatible(ty)
+    }
+}
+
+impl<'r, DB> Decode<'r, DB> for BString
+where
+    DB: Database,
+    Vec<u8>: Decode<'r, DB>,
+{
+    fn decode(value: <DB as HasValueRef<'r>>::ValueRef) -> Result<Self, BoxDynError> {
+        <Vec<u8> as Decode<DB>>::decode(value).map(BString::from)
+    }
+}
+
+impl<'q, DB: Database> Encode<'q, DB> for BString
+where
+    DB: Database,
+    [u8]: Encode<'q, DB>,
+{
+    fn encode_by_ref(&self, buf: &mut <DB as HasArguments<'q>>::ArgumentBuffer) -> IsNull {
+        <[u8] as Encode<DB>>::encode_by_ref(self.as_bytes(), buf)
+    }
+}

sqlx-core/src/types/mod.rs

@@ -20,6 +20,10 @@
 
 use crate::database::Database;
 
+#[cfg(feature = "bstr")]
+#[cfg_attr(docsrs, doc(cfg(feature = "bstr")))]
+mod bstr;
+
 #[cfg(feature = "json")]
 #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
 mod json;