components::ComponentContext Class Reference

Class to retrieve other components. More...

#include <userver/components/component_context.hpp>

Public Member Functions
template<typename T >
T &	FindComponent () const
	Finds a component of type T with specified name (if any) and returns the component after it was initialized. More...
template<typename T >
T &	FindComponent (std::string_view name) const
template<typename T >
T &	FindComponent (std::string_view={})
template<typename T >
T *	FindComponentOptional () const
	If there's no component with specified type and name return nullptr; otherwise behaves as FindComponent(). More...
template<typename T >
T *	FindComponentOptional (std::string_view name) const
template<typename T >
T &	FindComponentOptional (std::string_view={})
engine::TaskProcessor &	GetTaskProcessor (const std::string &name) const
	Returns an engine::TaskProcessor with the specified name.
template<typename T >
engine::TaskProcessor &	GetTaskProcessor (const T &)
const Manager &	GetManager () const
bool	IsAnyComponentInFatalState () const
bool	Contains (std::string_view name) const noexcept
template<typename T >
bool	Contains (const T &)

Friends
class	Manager

Detailed Description

Class to retrieve other components.

Only the const member functions of this class are meant for usage in component constructor (because of that this class is always passed as a const reference to the constructors).

See also

Components

Examples

components/component_sample_test.cpp, components/component_sample_test.hpp, postgresql/functional_tests/basic_chaos/postgres_service.cpp, samples/config_service/config_service.cpp, samples/flatbuf_service/flatbuf_service.cpp, samples/grpc_service/grpc_service.cpp, samples/http_caching/http_caching.cpp, samples/mongo_service/mongo_service.cpp, samples/postgres_service/postgres_service.cpp, samples/redis_service/redis_service.cpp, samples/tcp_full_duplex_service/tcp_full_duplex_service.cpp, samples/tcp_service/tcp_service.cpp, samples/testsuite-support/src/metrics.cpp, samples/testsuite-support/src/metrics.hpp, and samples/testsuite-support/src/tasks.cpp.

Definition at line 64 of file component_context.hpp.

Member Function Documentation

Contains() [1/2]

template<typename T >

bool components::ComponentContext::Contains ( const T &  )

inline

Definition at line 146 of file component_context.hpp.

Contains() [2/2]

bool components::ComponentContext::Contains ( std::string_view  name ) const

noexcept

Returns

true if there is a component with the specified name and it could be found via FindComponent()

FindComponent() [1/3]

template<typename T >

T & components::ComponentContext::FindComponent ( ) const

inline

Finds a component of type T with specified name (if any) and returns the component after it was initialized.

Can only be called from other component's constructor in a task where that constructor was called. May block and asynchronously wait for the creation of the requested component.

Exceptions

ComponentsLoadCancelledException	if components loading was cancelled due to errors in the creation of other component.
std::runtime_error	if component missing in component_list was requested.

Examples

components/component_sample_test.cpp, postgresql/functional_tests/basic_chaos/postgres_service.cpp, samples/grpc_service/grpc_service.cpp, samples/mongo_service/mongo_service.cpp, and samples/testsuite-support/src/metrics.cpp.

Definition at line 78 of file component_context.hpp.

FindComponent() [2/3]

template<typename T >

T & components::ComponentContext::FindComponent ( std::string_view  name ) const

inline

Definition at line 84 of file component_context.hpp.

FindComponent() [3/3]

template<typename T >

T & components::ComponentContext::FindComponent ( std::string_view  = {} )

inline

Definition at line 100 of file component_context.hpp.

FindComponentOptional() [1/3]

template<typename T >

T * components::ComponentContext::FindComponentOptional ( ) const

inline

If there's no component with specified type and name return nullptr; otherwise behaves as FindComponent().

Definition at line 107 of file component_context.hpp.

FindComponentOptional() [2/3]

template<typename T >

T * components::ComponentContext::FindComponentOptional ( std::string_view  name ) const

inline

Definition at line 113 of file component_context.hpp.

FindComponentOptional() [3/3]

template<typename T >

T & components::ComponentContext::FindComponentOptional ( std::string_view  = {} )

inline

Definition at line 121 of file component_context.hpp.

GetTaskProcessor()

template<typename T >

engine::TaskProcessor & components::ComponentContext::GetTaskProcessor ( const T &  )

inline

Definition at line 129 of file component_context.hpp.

IsAnyComponentInFatalState()

bool components::ComponentContext::IsAnyComponentInFatalState

(

)

const

Returns

true if one of the components is in fatal state and can not work. A component is in fatal state if the components::ComponentHealth::kFatal value is returned from the overridden components::LoggableComponentBase::GetComponentHealth().

Friends And Related Function Documentation

Manager

friend class Manager

friend

Definition at line 161 of file component_context.hpp.

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

• userver/components/component_context.hpp