feat!: improve serialization efficiency

Fixed-size objects are now written directly on the writer,
instead of being wrapped first into a ZBytes.
Slice like objects are also written on the writer,
but obviously prefixed by their size, like ZBytes.

Cargo.toml

@@ -154,9 +154,7 @@ secrecy = { version = "0.8.0", features = ["serde", "alloc"] }
 serde = { version = "1.0.210", default-features = false, features = [
   "derive",
 ] } # Default features are disabled due to usage in no_std crates
-serde_cbor = "0.11.2"
 serde_json = "1.0.128"
-serde-pickle = "1.1.1"
 serde_yaml = "0.9.34"
 static_init = "1.0.3"
 stabby = "36.1.1"

ci/valgrind-check/src/pub_sub/bin/z_pub_sub.rs

@@ -38,7 +38,7 @@ async fn main() {
                 sample.key_expr().as_str(),
                 sample
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e))
             );
         })

ci/valgrind-check/src/queryable_get/bin/z_queryable_get.rs

@@ -64,13 +64,13 @@ async fn main() {
                     sample.key_expr().as_str(),
                     sample
                         .payload()
-                        .deserialize::<String>()
+                        .try_deserialize::<String>()
                         .unwrap_or_else(|e| format!("{}", e))
                 ),
                 Err(err) => println!(
                     ">> Received (ERROR: '{}')",
                     err.payload()
-                        .deserialize::<String>()
+                        .try_deserialize::<String>()
                         .unwrap_or_else(|e| format!("{}", e))
                 ),
             }

commons/zenoh-buffers/src/zbuf.rs

@@ -494,6 +494,11 @@ impl<'a> ZBufWriter<'a> {
         self.zslice_writer = zbuf.slices.last_mut().unwrap().writer();
         self.zslice_writer.as_mut().unwrap()
     }
+
+    #[inline]
+    pub fn reserve(&mut self, additional: usize) {
+        self.zslice_writer().reserve(additional)
+    }
 }
 
 impl<'a> HasWriter for &'a mut ZBuf {

commons/zenoh-buffers/src/zslice.rs

@@ -143,10 +143,11 @@ impl ZSlice {
     // See https://github.com/eclipse-zenoh/zenoh/pull/1289#discussion_r1701796640
     #[inline]
     pub(crate) fn writer(&mut self) -> Option<ZSliceWriter> {
+        const MAX_REALLOC_SIZE: usize = 64;
         let vec = Arc::get_mut(&mut self.buf)?
             .as_any_mut()
             .downcast_mut::<Vec<u8>>()?;
-        if self.end == vec.len() {
+        if self.end == vec.len() && (vec.len() < vec.capacity() || vec.len() <= MAX_REALLOC_SIZE) {
             Some(ZSliceWriter {
                 vec,
                 end: &mut self.end,
@@ -294,6 +295,12 @@ pub(crate) struct ZSliceWriter<'a> {
     end: &'a mut usize,
 }
 
+impl ZSliceWriter<'_> {
+    pub(crate) fn reserve(&mut self, additional: usize) {
+        self.vec.reserve(additional)
+    }
+}
+
 impl Writer for ZSliceWriter<'_> {
     fn write(&mut self, bytes: &[u8]) -> Result<NonZeroUsize, DidntWrite> {
         let len = self.vec.write(bytes)?;

commons/zenoh-protocol/src/core/parameters.rs

@@ -374,6 +374,11 @@ impl<'s> From<Cow<'s, str>> for Parameters<'s> {
         }
     }
 }
+impl<'s> From<Parameters<'s>> for Cow<'s, str> {
+    fn from(value: Parameters<'s>) -> Self {
+        value.0
+    }
+}
 
 impl<'a> From<Parameters<'a>> for Cow<'_, Parameters<'a>> {
     fn from(props: Parameters<'a>) -> Self {

examples/examples/z_bytes.rs

@@ -21,15 +21,15 @@ fn main() {
     // Numeric: u8, u16, u32, u128, usize, i8, i16, i32, i128, isize, f32, f64
     let input = 1234_u32;
     let payload = ZBytes::from(input);
-    let output: u32 = payload.deserialize().unwrap();
+    let output: u32 = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::ZENOH_UINT32;
 
     // String
     let input = String::from("test");
     let payload = ZBytes::from(&input);
-    let output: String = payload.deserialize().unwrap();
+    let output: String = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::ZENOH_STRING;
@@ -38,18 +38,18 @@ fn main() {
     // See [`zenoh::bytes::ZBytes`] documentation for zero-copy behaviour.
     let input = Cow::from("test");
     let payload = ZBytes::from(&input);
-    let output: Cow<str> = payload.deserialize().unwrap();
+    let output: Cow<str> = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::ZENOH_STRING;
 
     // Vec<u8>: The deserialization should be infallible
     let input: Vec<u8> = vec![1, 2, 3, 4];
     let payload = ZBytes::from(&input);
-    let output: Vec<u8> = payload.deserialize().unwrap();
+    let output: Vec<u8> = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Deserialization of Vec<u8> is infallible. See https://docs.rs/unwrap-infallible/latest/unwrap_infallible/.
-    let output: Vec<u8> = payload.deserialize().unwrap_infallible();
+    let output: Vec<u8> = payload.try_deserialize().unwrap_infallible();
     assert_eq!(input, output);
     // Since the deserialization of `Vec<u8>` is infallible, then `ZBytes` can be infallibly converted into a `Vec<u8>`.
     let output: Vec<u8> = payload.into();
@@ -61,10 +61,10 @@ fn main() {
     // See [`zenoh::bytes::ZBytes`] documentation for zero-copy behaviour.
     let input = Cow::from(vec![1, 2, 3, 4]);
     let payload = ZBytes::from(&input);
-    let output: Cow<[u8]> = payload.deserialize().unwrap();
+    let output: Cow<[u8]> = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Deserialization of `Cow<[u8]>` is infallible. See https://docs.rs/unwrap-infallible/latest/unwrap_infallible/.
-    let output: Cow<[u8]> = payload.deserialize().unwrap_infallible();
+    let output: Cow<[u8]> = payload.try_deserialize().unwrap_infallible();
     assert_eq!(input, output);
     // Since the deserialization of `Cow<[u8]>` is infallible, then `ZBytes` can be infallibly converted into a `Cow<[u8]>`.
     let output: Vec<u8> = payload.into();
@@ -74,7 +74,7 @@ fn main() {
 
     // Writer & Reader
     // serialization
-    let mut bytes = ZBytes::empty();
+    let mut bytes = ZBytes::new();
     let mut writer = bytes.writer();
     let i1 = 1234_u32;
     let i2 = String::from("test");
@@ -94,7 +94,7 @@ fn main() {
     // Tuple
     let input = (1234_u32, String::from("test"));
     let payload = ZBytes::serialize(input.clone());
-    let output: (u32, String) = payload.deserialize().unwrap();
+    let output: (u32, String) = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
 
     // Iterator
@@ -116,7 +116,7 @@ fn main() {
     input.insert(0, String::from("abc"));
     input.insert(1, String::from("def"));
     let payload = ZBytes::from(input.clone());
-    let output = payload.deserialize::<HashMap<usize, String>>().unwrap();
+    let output = payload.try_deserialize::<HashMap<usize, String>>().unwrap();
     assert_eq!(input, output);
 
     // JSON
@@ -131,7 +131,7 @@ fn main() {
     }"#;
     let input: serde_json::Value = serde_json::from_str(data).unwrap();
     let payload = ZBytes::try_serialize(input.clone()).unwrap();
-    let output: serde_json::Value = payload.deserialize().unwrap();
+    let output: serde_json::Value = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::APPLICATION_JSON;
@@ -146,7 +146,7 @@ fn main() {
     "#;
     let input: serde_yaml::Value = serde_yaml::from_str(data).unwrap();
     let payload = ZBytes::try_serialize(input.clone()).unwrap();
-    let output: serde_yaml::Value = payload.deserialize().unwrap();
+    let output: serde_yaml::Value = payload.try_deserialize().unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::APPLICATION_YAML;
@@ -166,7 +166,7 @@ fn main() {
     };
     let payload = ZBytes::from(input.encode_to_vec());
     let output =
-        EntityInfo::decode(Cursor::new(payload.deserialize::<Cow<[u8]>>().unwrap())).unwrap();
+        EntityInfo::decode(Cursor::new(payload.try_deserialize::<Cow<[u8]>>().unwrap())).unwrap();
     assert_eq!(input, output);
     // Corresponding encoding to be used in operations like `.put()`, `.reply()`, etc.
     // let encoding = Encoding::APPLICATION_PROTOBUF;

examples/examples/z_bytes_shm.rs

@@ -62,7 +62,7 @@ fn main() {
     // branch to illustrate immutable access to SHM data
     {
         // deserialize ZBytes as an immutably borrowed zshm (ZBytes -> &zshm)
-        let borrowed_shm_buf: &zshm = payload.deserialize().unwrap();
+        let borrowed_shm_buf: &zshm = payload.try_deserialize().unwrap();
 
         // immutable API
         let _data: &[u8] = borrowed_shm_buf;

examples/examples/z_get.rs

@@ -49,7 +49,7 @@ async fn main() {
                 // Refer to z_bytes.rs to see how to deserialize different types of message
                 let payload = sample
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(
                     ">> Received ('{}': '{}')",
@@ -60,7 +60,7 @@ async fn main() {
             Err(err) => {
                 let payload = err
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(">> Received (ERROR: '{}')", payload);
             }

examples/examples/z_get_liveliness.rs

@@ -40,7 +40,7 @@ async fn main() {
             Err(err) => {
                 let payload = err
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(">> Received (ERROR: '{}')", payload);
             }

examples/examples/z_get_shm.rs

@@ -78,15 +78,15 @@ async fn main() {
         match reply.result() {
             Ok(sample) => {
                 print!(">> Received ('{}': ", sample.key_expr().as_str());
-                match sample.payload().deserialize::<&zshm>() {
+                match sample.payload().try_deserialize::<&zshm>() {
                     Ok(payload) => println!("'{}')", String::from_utf8_lossy(payload),),
                     Err(e) => println!("'Not a ShmBufInner: {:?}')", e),
                 }
             }
             Err(err) => {
                 let payload = err
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(">> Received (ERROR: '{}')", payload);
             }

examples/examples/z_pull.rs

@@ -43,7 +43,7 @@ async fn main() {
             Ok(sample) => {
                 let payload = sample
                     .payload()
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(
                     ">> [Subscriber] Pulled {} ('{}': '{}')... performing a computation of {:#?}",

examples/examples/z_queryable.rs

@@ -43,7 +43,7 @@ async fn main() {
             Some(query_payload) => {
                 // Refer to z_bytes.rs to see how to deserialize different types of message
                 let deserialized_payload = query_payload
-                    .deserialize::<String>()
+                    .try_deserialize::<String>()
                     .unwrap_or_else(|e| format!("{}", e));
                 println!(
                     ">> [Queryable ] Received Query '{}' with payload '{}'",

examples/examples/z_queryable_shm.rs

@@ -144,7 +144,7 @@ fn handle_bytes(bytes: &ZBytes) -> (&str, String) {
 
         // if Zenoh is built with SHM support and with SHM API  we can detect the exact buffer type
         #[cfg(all(feature = "shared-memory", feature = "unstable"))]
-        match bytes.deserialize::<&zshm>() {
+        match bytes.try_deserialize::<&zshm>() {
             Ok(_) => "SHM",
             Err(_) => "RAW",
         }
@@ -157,7 +157,7 @@ fn handle_bytes(bytes: &ZBytes) -> (&str, String) {
     //
     // Refer to z_bytes.rs to see how to deserialize different types of message
     let bytes_string = bytes
-        .deserialize::<String>()
+        .try_deserialize::<String>()
         .unwrap_or_else(|e| format!("{}", e));
 
     (bytes_type, bytes_string)

examples/examples/z_storage.rs

@@ -51,7 +51,7 @@ async fn main() {
         select!(
             sample = subscriber.recv_async() => {
                 let sample = sample.unwrap();
-                let payload = sample.payload().deserialize::<String>().unwrap_or_else(|e| format!("{}", e));
+                let payload = sample.payload().try_deserialize::<String>().unwrap_or_else(|e| format!("{}", e));
                 println!(">> [Subscriber] Received {} ('{}': '{}')", sample.kind(), sample.key_expr().as_str(),payload);
                 match sample.kind() {
                     SampleKind::Delete => stored.remove(&sample.key_expr().to_string()),

examples/examples/z_sub.rs

@@ -33,7 +33,7 @@ async fn main() {
         // Refer to z_bytes.rs to see how to deserialize different types of message
         let payload = sample
             .payload()
-            .deserialize::<String>()
+            .try_deserialize::<String>()
             .unwrap_or_else(|e| format!("{}", e));
 
         print!(
@@ -44,7 +44,7 @@ async fn main() {
         );
         if let Some(att) = sample.attachment() {
             let att = att
-                .deserialize::<String>()
+                .try_deserialize::<String>()
                 .unwrap_or_else(|e| format!("{}", e));
             print!(" ({})", att);
         }