clients::dns::Component Class Reference

#include <userver/clients/dns/component.hpp>

Detailed Description

Caching DNS resolver component.

Returned references to clients::dns::Resolver live for a lifetime of the component and are safe for concurrent use.

Static options:

Name	Description	Default value
fs-task-processor	task processor for disk I/O operations	-
hosts-file-path	path to the hosts file	/etc/hosts
hosts-file-update-interval	hosts file cache reload interval	5m
network-timeout	timeout for network requests	1s
network-attempts	number of attempts for network requests	1
network-custom-servers	list of name servers to use	from /etc/resolv.conf
cache-ways	number of ways for network cache	16
cache-size-per-way	size of each way of network cache	256
cache-max-reply-ttl	TTL limit for network replies caching	5m
cache-failure-ttl	TTL for network failures caching	5s

Static configuration example:

# yaml
    dns-client:
      fs-task-processor: fs-task-processor
      hosts-file-path: /etc/hosts
      hosts-file-update-interval: 5m
      network-timeout: 1s
      network-attempts: 1
      network-custom-servers:
        - 127.0.0.1
        - 127.0.0.2
      cache-ways: 16
      cache-size-per-way: 256
      cache-max-reply-ttl: 5m
      cache-failure-ttl: 5s

Examples

samples/http_caching/http_caching.cpp, samples/mongo_service/mongo_service.cpp, samples/postgres_auth/postgres_service.cpp, samples/redis_service/redis_service.cpp, and samples/tcp_full_duplex_service/tcp_full_duplex_service.cpp.

Definition at line 42 of file component.hpp.

Inheritance diagram for clients::dns::Component:

Collaboration diagram for clients::dns::Component:

Public Member Functions
	Component (const components::ComponentConfig &, const components::ComponentContext &)
Resolver &	GetResolver ()
Public Member Functions inherited from components::LoggableComponentBase
	LoggableComponentBase (const ComponentConfig &, const ComponentContext &)
	LoggableComponentBase (LoggableComponentBase &&)=delete
	LoggableComponentBase (const LoggableComponentBase &)=delete
	~LoggableComponentBase () override=default
ComponentHealth	GetComponentHealth () const override
void	OnLoadingCancelled () override
void	OnAllComponentsLoaded () override
void	OnAllComponentsAreStopping () override

Static Public Member Functions
static yaml_config::Schema	GetStaticConfigSchema ()
Static Public Member Functions inherited from components::LoggableComponentBase
static yaml_config::Schema	GetStaticConfigSchema ()

Static Public Attributes
static constexpr std::string_view	kName = "dns-client"
	The default name of clients::dns::Component component.

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

• userver/clients/dns/component.hpp