#[repr(transparent)]pub struct Metadata(_);Expand description
A collection of metadata entries that can be exchanged during a call.
gRPC supports these types of metadata:
-
Request headers
They are sent by the client at the beginning of a remote call before any request messages are sent.
-
Response headers
They are sent by the server at the beginning of a remote call handler before any response messages are sent.
-
Response trailers
They are sent by the server at the end of a remote call along with resulting call status.
Metadata value can be ascii string or bytes. They are distinguish by the key suffix, key of bytes value should have suffix ‘-bin’.
Implementations
sourceimpl Metadata
impl Metadata
sourcepub fn get(&self, index: usize) -> Option<(&str, &[u8])>
pub fn get(&self, index: usize) -> Option<(&str, &[u8])>
Returns the metadata entry at the index.
None is returned if out of bound.
sourcepub fn iter(&self) -> MetadataIter<'_>ⓘNotable traits for MetadataIter<'a>impl<'a> Iterator for MetadataIter<'a> type Item = (&'a str, &'a [u8]);
pub fn iter(&self) -> MetadataIter<'_>ⓘNotable traits for MetadataIter<'a>impl<'a> Iterator for MetadataIter<'a> type Item = (&'a str, &'a [u8]);
Returns an iterator over the metadata entries.
sourcepub fn into_raw_parts(self) -> (*mut grpc_metadata, usize, usize)
pub fn into_raw_parts(self) -> (*mut grpc_metadata, usize, usize)
Decomposes a Metadata array into its raw components.
Returns the raw pointer to the underlying data, the length of the vector (in elements), and the allocated capacity of the data (in elements). These are the same arguments in the same order as the arguments to from_raw_parts.
After calling this function, the caller is responsible for the memory previously managed by the Metadata. The only way to do this is to convert the raw pointer, length, and capacity back into a Metadata with the from_raw_parts function, allowing the destructor to perform the cleanup.
sourcepub unsafe fn from_raw_parts(
p: *mut grpc_metadata,
len: usize,
cap: usize
) -> Metadata
pub unsafe fn from_raw_parts(
p: *mut grpc_metadata,
len: usize,
cap: usize
) -> Metadata
Creates a Metadata directly from the raw components of another vector.
Safety
The operation is safe only if the three arguments are returned from into_raw_parts
and only convert once.
Trait Implementations
sourceimpl<'a> IntoIterator for &'a Metadata
impl<'a> IntoIterator for &'a Metadata
type IntoIter = MetadataIter<'a>
type IntoIter = MetadataIter<'a>
Which kind of iterator are we turning this into?
sourcefn into_iter(self) -> MetadataIter<'a>ⓘNotable traits for MetadataIter<'a>impl<'a> Iterator for MetadataIter<'a> type Item = (&'a str, &'a [u8]);
fn into_iter(self) -> MetadataIter<'a>ⓘNotable traits for MetadataIter<'a>impl<'a> Iterator for MetadataIter<'a> type Item = (&'a str, &'a [u8]);
Creates an iterator from a value. Read more
impl Send for Metadata
impl Sync for Metadata
Auto Trait Implementations
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcefn clone_into(&self, target: &mut T)
fn clone_into(&self, target: &mut T)
toowned_clone_into)Uses borrowed data to replace owned data, usually by cloning. Read more