dcontext_dactor/
header.rs

1use std::any::Any;
2
3use dactor::HeaderValue;
4use dcontext::ContextSnapshot;
5
6/// Header carrying serialized context bytes for wire transport.
7///
8/// Attached by [`ContextOutboundInterceptor`](crate::ContextOutboundInterceptor)
9/// on the sender side. Deserialized on the receiver side by
10/// [`ContextInboundInterceptor`](crate::ContextInboundInterceptor) or
11/// the handler via [`extract_context`](crate::extract_context).
12///
13/// For remote transport, register the deserializer with
14/// [`register_context_headers`](crate::register_context_headers) at startup.
15pub struct ContextHeader {
16    /// Serialized dcontext bytes (bincode wire format).
17    pub(crate) bytes: Vec<u8>,
18}
19
20impl ContextHeader {
21    /// Create a `ContextHeader` from raw wire bytes.
22    ///
23    /// Used by the `HeaderRegistry` deserializer to reconstruct this header
24    /// from bytes received over the wire.
25    pub fn from_bytes(bytes: Vec<u8>) -> Self {
26        Self { bytes }
27    }
28}
29
30impl HeaderValue for ContextHeader {
31    fn header_name(&self) -> &'static str {
32        "dcontext.wire"
33    }
34
35    /// Returns the serialized bytes for remote transport.
36    fn to_bytes(&self) -> Option<Vec<u8>> {
37        Some(self.bytes.clone())
38    }
39
40    fn as_any(&self) -> &dyn Any {
41        self
42    }
43}
44
45/// Header carrying a `ContextSnapshot` for in-process (local) propagation.
46///
47/// This preserves local-only context values that would be lost during
48/// serialization. Preferred over [`ContextHeader`] for same-process actors.
49pub struct ContextSnapshotHeader {
50    pub(crate) snapshot: ContextSnapshot,
51}
52
53impl HeaderValue for ContextSnapshotHeader {
54    fn header_name(&self) -> &'static str {
55        "dcontext.snapshot"
56    }
57
58    /// Returns `None` — snapshots are local-only and not sent over the wire.
59    fn to_bytes(&self) -> Option<Vec<u8>> {
60        None
61    }
62
63    fn as_any(&self) -> &dyn Any {
64        self
65    }
66}
dcontext_dactor/header.rs

dcontext_dactor/
header.rs
