OptionPayload for API ergonomicity

examples/examples/z_pub.rs

@@ -35,16 +35,12 @@ async fn main() {
         tokio::time::sleep(Duration::from_secs(1)).await;
         let buf = format!("[{idx:4}] {value}");
         println!("Putting Data ('{}': '{}')...", &key_expr, buf);
-        let mut put = publisher.put(buf);
-        if let Some(attachment) = &attachment {
-            put = put.attachment(Some(
-                attachment
-                    .split('&')
-                    .map(|pair| split_once(pair, '='))
-                    .collect(),
-            ))
-        }
-        put.res().await.unwrap();
+        publisher
+            .put(buf)
+            .attachment(&attachment)
+            .res()
+            .await
+            .unwrap();
     }
 }
 
@@ -65,17 +61,6 @@ struct Args {
     common: CommonArgs,
 }
 
-fn split_once(s: &str, c: char) -> (&[u8], &[u8]) {
-    let s_bytes = s.as_bytes();
-    match s.find(c) {
-        Some(index) => {
-            let (l, r) = s_bytes.split_at(index);
-            (l, &r[1..])
-        }
-        None => (s_bytes, &[]),
-    }
-}
-
 fn parse_args() -> (Config, KeyExpr<'static>, String, Option<String>) {
     let args = Args::parse();
     (args.common.into(), args.key, args.value, args.attach)

examples/examples/z_sub.rs

@@ -40,12 +40,19 @@ async fn main() {
             .payload()
             .deserialize::<String>()
             .unwrap_or_else(|e| format!("{}", e));
-        println!(
+        print!(
             ">> [Subscriber] Received {} ('{}': '{}')",
             sample.kind(),
             sample.key_expr().as_str(),
             payload
         );
+        if let Some(att) = sample.attachment() {
+            let att = att
+                .deserialize::<String>()
+                .unwrap_or_else(|e| format!("{}", e));
+            print!(" ({})", att);
+        }
+        println!();
     }
 }
 

zenoh/src/payload.rs

@@ -231,6 +231,50 @@ where
     }
 }
 
+/// Wrapper type for API ergonomicity to allow any type `T` to be converted into `Option<Payload>` where `T` implements `Into<Payload>`.
+#[repr(transparent)]
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub struct OptionPayload(Option<Payload>);
+
+impl<T> From<T> for OptionPayload
+where
+    T: Into<Payload>,
+{
+    fn from(value: T) -> Self {
+        Self(Some(value.into()))
+    }
+}
+
+impl<T> From<Option<T>> for OptionPayload
+where
+    T: Into<Payload>,
+{
+    fn from(mut value: Option<T>) -> Self {
+        match value.take() {
+            Some(v) => Self(Some(v.into())),
+            None => Self(None),
+        }
+    }
+}
+
+impl<T> From<&Option<T>> for OptionPayload
+where
+    for<'a> &'a T: Into<Payload>,
+{
+    fn from(value: &Option<T>) -> Self {
+        match value.as_ref() {
+            Some(v) => Self(Some(v.into())),
+            None => Self(None),
+        }
+    }
+}
+
+impl From<OptionPayload> for Option<Payload> {
+    fn from(value: OptionPayload) -> Self {
+        value.0
+    }
+}
+
 /// The default serializer for Zenoh payload. It supports primitives types, such as: vec<u8>, int, uint, float, string, bool.
 /// It also supports common Rust serde values.
 #[derive(Clone, Copy, Debug)]

zenoh/src/publication.rs

@@ -14,6 +14,7 @@
 
 //! Publishing primitives.
 use crate::net::primitives::Primitives;
+use crate::payload::OptionPayload;
 use crate::prelude::*;
 #[zenoh_macros::unstable]
 use crate::sample::Attachment;
@@ -167,7 +168,8 @@ impl<P, T> SampleBuilderTrait for PublicationBuilder<P, T> {
         }
     }
     #[cfg(feature = "unstable")]
-    fn attachment<TA: Into<Option<Attachment>>>(self, attachment: TA) -> Self {
+    fn attachment<TA: Into<OptionPayload>>(self, attachment: TA) -> Self {
+        let attachment: OptionPayload = attachment.into();
         Self {
             attachment: attachment.into(),
             ..self

zenoh/src/query.rs

@@ -14,6 +14,7 @@
 
 //! Query primitives.
 use crate::handlers::{locked, Callback, DefaultHandler};
+use crate::payload::OptionPayload;
 use crate::prelude::*;
 #[zenoh_macros::unstable]
 use crate::sample::Attachment;
@@ -144,7 +145,8 @@ impl<Handler> SampleBuilderTrait for GetBuilder<'_, '_, Handler> {
     }
 
     #[cfg(feature = "unstable")]
-    fn attachment<T: Into<Option<Attachment>>>(self, attachment: T) -> Self {
+    fn attachment<T: Into<OptionPayload>>(self, attachment: T) -> Self {
+        let attachment: OptionPayload = attachment.into();
         Self {
             attachment: attachment.into(),
             ..self

zenoh/src/queryable.rs

@@ -17,6 +17,7 @@
 use crate::encoding::Encoding;
 use crate::handlers::{locked, DefaultHandler};
 use crate::net::primitives::Primitives;
+use crate::payload::OptionPayload;
 use crate::prelude::*;
 use crate::sample::builder::SampleBuilder;
 use crate::sample::QoSBuilder;
@@ -308,7 +309,8 @@ impl<T> TimestampBuilderTrait for ReplyBuilder<'_, '_, T> {
 #[cfg(feature = "unstable")]
 impl<T> SampleBuilderTrait for ReplyBuilder<'_, '_, T> {
     #[cfg(feature = "unstable")]
-    fn attachment<U: Into<Option<Attachment>>>(self, attachment: U) -> Self {
+    fn attachment<U: Into<OptionPayload>>(self, attachment: U) -> Self {
+        let attachment: OptionPayload = attachment.into();
         Self {
             attachment: attachment.into(),
             ..self

zenoh/src/sample/builder.rs

@@ -14,8 +14,9 @@
 
 use std::marker::PhantomData;
 
+use crate::payload::OptionPayload;
 #[cfg(feature = "unstable")]
-use crate::sample::{Attachment, SourceInfo};
+use crate::sample::SourceInfo;
 use crate::sample::{QoS, QoSBuilder};
 use crate::Encoding;
 use crate::KeyExpr;
@@ -51,7 +52,7 @@ pub trait SampleBuilderTrait {
     fn source_info(self, source_info: SourceInfo) -> Self;
     /// Attach user-provided data in key-value format
     #[zenoh_macros::unstable]
-    fn attachment<T: Into<Option<Attachment>>>(self, attachment: T) -> Self;
+    fn attachment<T: Into<OptionPayload>>(self, attachment: T) -> Self;
 }
 
 pub trait ValueBuilderTrait {
@@ -177,7 +178,8 @@ impl<T> SampleBuilderTrait for SampleBuilder<T> {
     }
 
     #[zenoh_macros::unstable]
-    fn attachment<U: Into<Option<Attachment>>>(self, attachment: U) -> Self {
+    fn attachment<U: Into<OptionPayload>>(self, attachment: U) -> Self {
+        let attachment: OptionPayload = attachment.into();
         Self {
             sample: Sample {
                 attachment: attachment.into(),