Module metadata 

gRPC metadata handling.

gRPC metadata is a map of keys to values, similar to HTTP headers. This module provides types for working with metadata, including ASCII and binary values.

Key Concepts

• MetadataMap: The main struct for holding metadata.
• MetadataKey: Represents a key in the metadata map.
• MetadataValue: Represents a value in the metadata map.

Modules

errors

The metadata::errors module contains types for errors that can occur while handling gRPC custom metadata.

Structs

GetAll

A view to all values stored in a single entry.

Iter

MetadataMap entry iterator.

MetadataKey

Represents a custom metadata field name.

MetadataMap

A set of gRPC custom metadata entries.

MetadataValue

Represents a custom metadata field value.

ValueIter

An iterator of all values associated with a single metadata key.

Enums

Ascii

gRPC metadata values can be either ASCII strings or binary. Note that only visible ASCII characters (32-127) are permitted. This type should never be instantiated – in fact, it’s impossible to, because there are no variants to instantiate. Instead, it’s just used as a type parameter for MetadataKey and MetadataValue.

Binary

gRPC metadata values can be either ASCII strings or binary. This type should never be instantiated – in fact, it’s impossible to, because there are no variants to instantiate. Instead, it’s just used as a type parameter for MetadataKey and MetadataValue.

Key

Reference to a key in a MetadataMap. It can point to either an ascii or a binary (“*-bin”) key.

KeyAndValueRef

Reference to a key and an associated value in a MetadataMap. It can point to either an ascii or a binary (“*-bin”) key.

Type Aliases

AsciiMetadataKey

An ascii metadata key.

AsciiMetadataValue

An ascii metadata value.

BinaryMetadataKey

A binary metadata key.

BinaryMetadataValue

A binary metadata value.