Struct tower_grpc::metadata::MetadataKey

#[repr(transparent)]
pub struct MetadataKey<VE: ValueEncoding> { /* fields omitted */ }

Represents a custom metadata field name.

MetadataKey is used as the [MetadataMap] key.

Methods

impl<VE: ValueEncoding> MetadataKey<VE>

pub fn from_bytes(src: &[u8]) -> Result<Self, InvalidMetadataKey>

Converts a slice of bytes to a MetadataKey.

This function normalizes the input.

pub fn from_static(src: &'static str) -> Self

Converts a static string to a MetadataKey.

This function panics when the static string is a invalid metadata key.

This function requires the static string to only contain lowercase characters, numerals and symbols, as per the HTTP/2.0 specification and header names internal representation within this library.

Examples

// Parsing a metadata key
let CUSTOM_KEY: &'static str = "custom-key";

let a = AsciiMetadataKey::from_bytes(b"custom-key").unwrap();
let b = AsciiMetadataKey::from_static(CUSTOM_KEY);
assert_eq!(a, b);

// Parsing a metadata key that contains invalid symbols(s):
AsciiMetadataKey::from_static("content{}{}length"); // This line panics!

// Parsing a metadata key that contains invalid uppercase characters.
let a = AsciiMetadataKey::from_static("foobar");
let b = AsciiMetadataKey::from_static("FOOBAR"); // This line panics!

// Parsing a -bin metadata key as an Ascii key.
let b = AsciiMetadataKey::from_static("hello-bin"); // This line panics!

// Parsing a non-bin metadata key as an Binary key.
let b = BinaryMetadataKey::from_static("hello"); // This line panics!

pub fn as_str(&self) -> &str

Returns a str representation of the metadata key.

The returned string will always be lower case.

Trait Implementations

impl<'a, VE: ValueEncoding> From<&'a MetadataKey<VE>> for MetadataKey<VE>

fn from(src: &'a MetadataKey<VE>) -> MetadataKey<VE>

Performs the conversion.

impl<VE: ValueEncoding> From<MetadataKey<VE>> for Bytes

fn from(name: MetadataKey<VE>) -> Bytes

Performs the conversion.

impl<KeyVE: ValueEncoding> From<MetadataKey<KeyVE>> for MetadataValue<Ascii>

fn from(h: MetadataKey<KeyVE>) -> MetadataValue<Ascii>

Performs the conversion.

impl<VE: ValueEncoding> AsRef<str> for MetadataKey<VE>

fn as_ref(&self) -> &str

Performs the conversion.

impl<VE: ValueEncoding> AsRef<[u8]> for MetadataKey<VE>

fn as_ref(&self) -> &[u8]

Performs the conversion.

impl<VE: Clone + ValueEncoding> Clone for MetadataKey<VE>

fn clone(&self) -> MetadataKey<VE>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<VE: PartialEq + ValueEncoding> PartialEq<MetadataKey<VE>> for MetadataKey<VE>

fn eq(&self, other: &MetadataKey<VE>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &MetadataKey<VE>) -> bool

This method tests for !=.

impl<'a, VE: ValueEncoding> PartialEq<&'a MetadataKey<VE>> for MetadataKey<VE>

fn eq(&self, other: &&'a MetadataKey<VE>) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, VE: ValueEncoding> PartialEq<MetadataKey<VE>> for &'a MetadataKey<VE>

fn eq(&self, other: &MetadataKey<VE>) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<VE: ValueEncoding> PartialEq<str> for MetadataKey<VE>

fn eq(&self, other: &str) -> bool

Performs a case-insensitive comparison of the string against the header name

Examples

let content_length = AsciiMetadataKey::from_static("content-length");

assert_eq!(content_length, "content-length");
assert_eq!(content_length, "Content-Length");
assert_ne!(content_length, "content length");

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<VE: ValueEncoding> PartialEq<MetadataKey<VE>> for str

fn eq(&self, other: &MetadataKey<VE>) -> bool

Performs a case-insensitive comparison of the string against the header name

Examples

let content_length = AsciiMetadataKey::from_static("content-length");

assert_eq!(content_length, "content-length");
assert_eq!(content_length, "Content-Length");
assert_ne!(content_length, "content length");

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, VE: ValueEncoding> PartialEq<&'a str> for MetadataKey<VE>

fn eq(&self, other: &&'a str) -> bool

Performs a case-insensitive comparison of the string against the header name

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, VE: ValueEncoding> PartialEq<MetadataKey<VE>> for &'a str

fn eq(&self, other: &MetadataKey<VE>) -> bool

Performs a case-insensitive comparison of the string against the header name

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<VE: Eq + ValueEncoding> Eq for MetadataKey<VE>

impl<VE: ValueEncoding> Display for MetadataKey<VE>

fn fmt(&self, fmt: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<VE: ValueEncoding> Debug for MetadataKey<VE>

fn fmt(&self, fmt: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<VE: Hash + ValueEncoding> Hash for MetadataKey<VE>

fn hash<__HVE: Hasher>(&self, state: &mut __HVE)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<VE: ValueEncoding> FromStr for MetadataKey<VE>

type Err = InvalidMetadataKey

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, InvalidMetadataKey>

Parses a string s to return a value of this type.

impl<VE: ValueEncoding> Borrow<str> for MetadataKey<VE>

fn borrow(&self) -> &str

Immutably borrows from an owned value.