GRPC C++  1.66.0
Public Member Functions | Friends
grpc::ServerContext Class Reference

A ServerContext or CallbackServerContext allows the code implementing a service handler to: More...

#include <server_context.h>

Public Member Functions

 ServerContext ()
 
void AddInitialMetadata (const std::string &key, const std::string &value)
 Add the (key, value) pair to the initial metadata associated with a server call. More...
 
void AddTrailingMetadata (const std::string &key, const std::string &value)
 Add the (key, value) pair to the initial metadata associated with a server call. More...
 
std::shared_ptr< const grpc::AuthContextauth_context () const
 Return the authentication context for this server call. More...
 
grpc_callc_call ()
 Should be used for framework-level extensions only. More...
 
const struct census_contextcensus_context () const
 Get the census context associated with this server call. More...
 
const std::multimap< grpc::string_ref, grpc::string_ref > & client_metadata () const
 Return a collection of initial metadata key-value pairs sent from the client. More...
 
grpc_compression_algorithm compression_algorithm () const
 Return the compression algorithm the server call will request be used. More...
 
grpc_compression_level compression_level () const
 Return the compression algorithm to be used by the server call. More...
 
bool compression_level_set () const
 Return a bool indicating whether the compression level for this call has been set (either implicitly or through a previous call to set_compression_level. More...
 
std::chrono::system_clock::time_point deadline () const
 Return the deadline for the server call. More...
 
bool IsCancelled () const
 Return whether this RPC failed before the server could provide its status back to the client. More...
 
std::string peer () const
 Return the peer uri in a string. More...
 
gpr_timespec raw_deadline () const
 Return a gpr_timespec representation of the server call's deadline. More...
 
void set_compression_algorithm (grpc_compression_algorithm algorithm)
 Set algorithm to be the compression algorithm used for the server call. More...
 
void set_compression_level (grpc_compression_level level)
 Set level to be the compression level used for the server call. More...
 
void SetLoadReportingCosts (const std::vector< std::string > &cost_data)
 Set the serialized load reporting costs in cost_data for the call. More...
 
void TryCancel () const
 Cancel the Call from the server. More...
 
void AsyncNotifyWhenDone (void *tag)
 Async only. More...
 
- Public Member Functions inherited from grpc::ServerContextBase
virtual ~ServerContextBase ()
 
std::chrono::system_clock::time_point deadline () const
 Return the deadline for the server call. More...
 
gpr_timespec raw_deadline () const
 Return a gpr_timespec representation of the server call's deadline. More...
 
void AddInitialMetadata (const std::string &key, const std::string &value)
 Add the (key, value) pair to the initial metadata associated with a server call. More...
 
void AddTrailingMetadata (const std::string &key, const std::string &value)
 Add the (key, value) pair to the initial metadata associated with a server call. More...
 
bool IsCancelled () const
 Return whether this RPC failed before the server could provide its status back to the client. More...
 
void TryCancel () const
 Cancel the Call from the server. More...
 
const std::multimap< grpc::string_ref, grpc::string_ref > & client_metadata () const
 Return a collection of initial metadata key-value pairs sent from the client. More...
 
grpc_compression_level compression_level () const
 Return the compression algorithm to be used by the server call. More...
 
void set_compression_level (grpc_compression_level level)
 Set level to be the compression level used for the server call. More...
 
bool compression_level_set () const
 Return a bool indicating whether the compression level for this call has been set (either implicitly or through a previous call to set_compression_level. More...
 
grpc_compression_algorithm compression_algorithm () const
 Return the compression algorithm the server call will request be used. More...
 
void set_compression_algorithm (grpc_compression_algorithm algorithm)
 Set algorithm to be the compression algorithm used for the server call. More...
 
void SetLoadReportingCosts (const std::vector< std::string > &cost_data)
 Set the serialized load reporting costs in cost_data for the call. More...
 
std::shared_ptr< const grpc::AuthContextauth_context () const
 Return the authentication context for this server call. More...
 
std::string peer () const
 Return the peer uri in a string. More...
 
const struct census_contextcensus_context () const
 Get the census context associated with this server call. More...
 
grpc_callc_call ()
 Should be used for framework-level extensions only. More...
 
experimental::CallMetricRecorderExperimentalGetCallMetricRecorder ()
 Get the CallMetricRecorder object for the current RPC. More...
 
grpc::string_ref ExperimentalGetAuthority () const
 EXPERIMENTAL API Returns the call's authority. More...
 

Friends

class grpc::Server
 

Additional Inherited Members

- Protected Member Functions inherited from grpc::ServerContextBase
void AsyncNotifyWhenDone (void *tag)
 Async only. More...
 
RpcAllocatorStateGetRpcAllocatorState ()
 NOTE: This is an API for advanced users who need custom allocators. More...
 
grpc::ServerUnaryReactorDefaultReactor ()
 Get a library-owned default unary reactor for use in minimal reaction cases. More...
 
 ServerContextBase ()
 Constructors for use by derived classes. More...
 
 ServerContextBase (gpr_timespec deadline, grpc_metadata_array *arr)
 
void set_context_allocator (ContextAllocator *context_allocator)
 
ContextAllocatorcontext_allocator () const
 

Detailed Description

A ServerContext or CallbackServerContext allows the code implementing a service handler to:

Context settings are only relevant to the call handler they are supplied to, that is to say, they aren't sticky across multiple calls. Some of these settings, such as the compression options, can be made persistent at server construction time by specifying the appropriate ChannelArguments to a grpc::ServerBuilder, via ServerBuilder::AddChannelArgument.

Warning
ServerContext instances should not be reused across rpcs.

Constructor & Destructor Documentation

◆ ServerContext()

grpc::ServerContext::ServerContext ( )
inline

Member Function Documentation

◆ AddInitialMetadata()

void grpc::ServerContextBase::AddInitialMetadata

Add the (key, value) pair to the initial metadata associated with a server call.

These are made available at the client side by the grpc::ClientContext::GetServerInitialMetadata() method.

Warning
This method should only be called before sending initial metadata to the client (which can happen explicitly, or implicitly when sending a a response message or status to the client).
Parameters
keyThe metadata key. If value is binary data, it must end in "-bin".
valueThe metadata value. If its value is binary, the key name must end in "-bin".

Metadata must conform to the following format:

*  Custom-Metadata -> Binary-Header / ASCII-Header
*  Binary-Header -> {Header-Name "-bin" } {binary value}
*  ASCII-Header -> Header-Name ASCII-Value
*  Header-Name -> 1*( %x30-39 / %x61-7A / "_" / "-" / ".") ; 0-9 a-z _ - .
*  ASCII-Value -> 1*( %x20-%x7E ) ; space and printable ASCII
* 

◆ AddTrailingMetadata()

void grpc::ServerContextBase::AddTrailingMetadata

Add the (key, value) pair to the initial metadata associated with a server call.

These are made available at the client side by the grpc::ClientContext::GetServerTrailingMetadata() method.

Warning
This method should only be called before sending trailing metadata to the client (which happens when the call is finished and a status is sent to the client).
Parameters
keyThe metadata key. If value is binary data, it must end in "-bin".
valueThe metadata value. If its value is binary, the key name must end in "-bin".

Metadata must conform to the following format:

*  Custom-Metadata -> Binary-Header / ASCII-Header
*  Binary-Header -> {Header-Name "-bin" } {binary value}
*  ASCII-Header -> Header-Name ASCII-Value
*  Header-Name -> 1*( %x30-39 / %x61-7A / "_" / "-" / ".") ; 0-9 a-z _ - .
*  ASCII-Value -> 1*( %x20-%x7E ) ; space and printable ASCII
* 

◆ AsyncNotifyWhenDone()

void grpc::ServerContextBase::AsyncNotifyWhenDone
inline

Async only.

Has to be called before the rpc starts. Returns the tag in completion queue when the rpc finishes. IsCancelled() can then be called to check whether the rpc was cancelled. Note: the tag will only be returned if call starts. If the call never starts, this tag will not be returned.

◆ auth_context()

std::shared_ptr<const grpc::AuthContext> grpc::ServerContextBase::auth_context
inline

Return the authentication context for this server call.

See also
grpc::AuthContext.

◆ c_call()

grpc_call* grpc::ServerContextBase::c_call
inline

Should be used for framework-level extensions only.

Applications never need to call this method.

◆ census_context()

const struct census_context* grpc::ServerContextBase::census_context

Get the census context associated with this server call.

◆ client_metadata()

const std::multimap<grpc::string_ref, grpc::string_ref>& grpc::ServerContextBase::client_metadata
inline

Return a collection of initial metadata key-value pairs sent from the client.

Note that keys may happen more than once (ie, a std::multimap is returned).

It is safe to use this method after initial metadata has been received, Calls always begin with the client sending initial metadata, so this is safe to access as soon as the call has begun on the server side.

Returns
A multimap of initial metadata key-value pairs from the server.

◆ compression_algorithm()

grpc_compression_algorithm grpc::ServerContextBase::compression_algorithm
inline

Return the compression algorithm the server call will request be used.

Note that the gRPC runtime may decide to ignore this request, for example, due to resource constraints, or if the server is aware the client doesn't support the requested algorithm.

◆ compression_level()

grpc_compression_level grpc::ServerContextBase::compression_level
inline

Return the compression algorithm to be used by the server call.

◆ compression_level_set()

bool grpc::ServerContextBase::compression_level_set
inline

Return a bool indicating whether the compression level for this call has been set (either implicitly or through a previous call to set_compression_level.

◆ deadline()

std::chrono::system_clock::time_point grpc::ServerContextBase::deadline
inline

Return the deadline for the server call.

◆ IsCancelled()

bool grpc::ServerContextBase::IsCancelled

Return whether this RPC failed before the server could provide its status back to the client.

This could be because of explicit API cancellation from the client-side or server-side, because of deadline exceeded, network connection reset, HTTP/2 parameter configuration (e.g., max message size, max connection age), etc. It does NOT include failure due to a non-OK status return from the server application's request handler, including Status::CANCELLED.

IsCancelled is always safe to call when using sync or callback API. When using async API, it is only safe to call IsCancelled after the AsyncNotifyWhenDone tag has been delivered. Thread-safe.

◆ peer()

std::string grpc::ServerContextBase::peer

Return the peer uri in a string.

WARNING: this value is never authenticated or subject to any security related code. It must not be used for any authentication related functionality. Instead, use auth_context.

◆ raw_deadline()

gpr_timespec grpc::ServerContextBase::raw_deadline
inline

Return a gpr_timespec representation of the server call's deadline.

◆ set_compression_algorithm()

void grpc::ServerContextBase::set_compression_algorithm

Set algorithm to be the compression algorithm used for the server call.

Parameters
algorithmThe compression algorithm used for the server call.

◆ set_compression_level()

void grpc::ServerContextBase::set_compression_level
inline

Set level to be the compression level used for the server call.

Parameters
levelThe compression level used for the server call.

◆ SetLoadReportingCosts()

void grpc::ServerContextBase::SetLoadReportingCosts

Set the serialized load reporting costs in cost_data for the call.

◆ TryCancel()

void grpc::ServerContextBase::TryCancel

Cancel the Call from the server.

This is a best-effort API and depending on when it is called, the RPC may still appear successful to the client. For example, if TryCancel() is called on a separate thread, it might race with the server handler which might return success to the client before TryCancel() was even started by the thread.

It is the caller's responsibility to prevent such races and ensure that if TryCancel() is called, the serverhandler must return Status::CANCELLED. The only exception is that if the serverhandler is already returning an error status code, it is ok to not return Status::CANCELLED even if TryCancel() was called. Additionally, it is illegal to invoke TryCancel() before the call has actually begun, i.e., before metadata has been received from the client.

For reasons such as the above, it is generally preferred to explicitly finish an RPC by returning Status::CANCELLED rather than using TryCancel.

Note that TryCancel() does not change any of the tags that are pending on the completion queue. All pending tags will still be delivered (though their ok result may reflect the effect of cancellation).

Friends And Related Function Documentation

◆ grpc::Server

friend class grpc::Server
friend

The documentation for this class was generated from the following file: