<QGrpcInterceptor> - Interceptor types

The <QGrpcInterceptor> header file provides the basic interceptor types. More...

Header:	`#include <QGrpcInterceptor>`
Since:	Qt 6.11

Types

`(since 6.11)` flags	InterceptorCapabilities
`(since 6.11)` enum class	InterceptorCapability { Start, InitialMetadata, MessageReceived, WriteMessage, WritesDone, …, Cancel }

Detailed Description

Qt GRPC provides various types that are commonly grouped in the <QtGrpcInterceptor> header file.

For an introduction to the interception mechanism and how interceptor interfaces participate in the lifecycle of an RPC, see the Qt GRPC Interceptors Overview.

Qt GRPC provides the following interceptor interfaces as hook points in the RPC lifecycle:

Interface	Hook Point	Direction	Can Modify
QGrpcStartInterceptor	Before the RPC is initiated	Outbound	Initial message object, call options
QGrpcWriteMessageInterceptor	Before an outgoing message is written	Outbound	Message object
QGrpcWritesDoneInterceptor	When the client indicates writes are done	Outbound	—
QGrpcCancelInterceptor	When the RPC is cancelled	Outbound	—
QGrpcInitialMetadataInterceptor	When initial metadata is received	Inbound	Metadata
QGrpcMessageReceivedInterceptor	When a message payload is received	Inbound	Serialized message data
QGrpcTrailingMetadataInterceptor	When trailing metadata is received	Inbound	Metadata
QGrpcFinishedInterceptor	When the RPC completes	Inbound	Final status

Interceptor mechanism

The following classes and pages form the Qt GRPC interceptor mechanism:

Type Documentation

`[since 6.11]` enum class InterceptorCapability
`[since 6.11]` flags InterceptorCapabilities

Specifies interception hook points supported by an interceptor.

Qt GRPC uses InterceptorCapability values to describe which interception hook points an interceptor provides.

A single interceptor class can implement multiple interceptor interfaces (for example, QGrpcStartInterceptor and QGrpcFinishedInterceptor) and therefore support multiple capabilities.

Constant	Value	Description
`InterceptorCapability::Start`	`0x01`	The interceptor implements QGrpcStartInterceptor.
`InterceptorCapability::InitialMetadata`	`0x02`	The interceptor implements QGrpcInitialMetadataInterceptor.
`InterceptorCapability::MessageReceived`	`0x04`	The interceptor implements QGrpcMessageReceivedInterceptor.
`InterceptorCapability::WriteMessage`	`0x08`	The interceptor implements QGrpcWriteMessageInterceptor.
`InterceptorCapability::WritesDone`	`0x10`	The interceptor implements QGrpcWritesDoneInterceptor.
`InterceptorCapability::TrailingMetadata`	`0x20`	The interceptor implements QGrpcTrailingMetadataInterceptor.
`InterceptorCapability::Finished`	`0x40`	The interceptor implements QGrpcFinishedInterceptor.
`InterceptorCapability::Cancel`	`0x80`	The interceptor implements QGrpcCancelInterceptor.

This enum was introduced in Qt 6.11.

The InterceptorCapabilities type is a typedef for QFlags<InterceptorCapability>. It stores an OR combination of InterceptorCapability values.