RUST-1119 Add bson::to_raw_document_buf function (#330)

Author: patrickfreed

src/lib.rs

@@ -278,12 +278,12 @@ pub use self::{
     },
     decimal128::Decimal128,
     raw::{
-        RawBson, RawArray, RawArrayBuf, RawBinaryRef, RawBsonRef, RawDbPointerRef, RawDocument,
+        RawArray, RawArrayBuf, RawBinaryRef, RawBson, RawBsonRef, RawDbPointerRef, RawDocument,
         RawDocumentBuf, RawJavaScriptCodeWithScopeRef, RawRegexRef,
     },
     ser::{
-        to_bson, to_bson_with_options, to_document, to_document_with_options, to_vec, Serializer,
-        SerializerOptions,
+        to_bson, to_bson_with_options, to_document, to_document_with_options, to_raw_document_buf,
+        to_vec, Serializer, SerializerOptions,
     },
     uuid::{Uuid, UuidRepresentation},
 };

src/ser/mod.rs

@@ -37,6 +37,7 @@ use crate::{
     de::MAX_BSON_SIZE,
     spec::BinarySubtype,
     Binary,
+    RawDocumentBuf,
 };
 use ::serde::{ser::Error as SerdeError, Serialize};
 
@@ -283,3 +284,28 @@ where
     value.serialize(&mut serializer)?;
     Ok(serializer.into_vec())
 }
+
+/// Serialize the given `T` as a [`RawDocumentBuf`].
+///
+/// ```rust
+/// use serde::Serialize;
+/// use bson::rawdoc;
+///
+/// #[derive(Serialize)]
+/// struct Cat {
+///     name: String,
+///     age: i32
+/// }
+///
+/// let cat = Cat { name: "Garfield".to_string(), age: 43 };
+/// let doc = bson::to_raw_document_buf(&cat)?;
+/// assert_eq!(doc, rawdoc! { "name": "Garfield", "age": 43 });
+/// # Ok::<(), Box<dyn std::error::Error>>(())
+/// ```
+#[inline]
+pub fn to_raw_document_buf<T>(value: &T) -> Result<RawDocumentBuf>
+where
+    T: Serialize,
+{
+    RawDocumentBuf::from_bytes(to_vec(value)?).map_err(Error::custom)
+}