Clients

Detailed Description

Clients are classes that provide interfaces for requesting and retrieving data usually from remote server.

All the clients are asynchronous. In other words, a request suspends the current engine::Task and other coroutines are processed on the task processor. The suspended task resumes execution on the task processor after the data was retrieved.

It is a common practice to return references or smart pointers to clients from a component. In such cases:

• a client lives as long as the component is alive
• and it is safe to invoke member functions of the same client instance concurrently if not stated the opposite.

See also

Component system for information on how to configure clients

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⇦ Component system | HTTP Handlers ⇨

Classes
class	alerts::Storage
	Storage for active fired alerts. More...
class	baggage::BaggageManager
class	clients::dns::Resolver
	Caching DNS resolver implementation. More...
class	clients::http::Client
	HTTP client that returns a HTTP request builder from CreateRequest(). More...
class	dynamic_config::Client
	Client for the dynamic configs service. More...
class	dynamic_config::Source
	A client for easy dynamic config fetching in components. More...
class	engine::subprocess::ProcessStarter
	Creates a new OS subprocess and executes a command in it. More...
class	fs::FsCacheClient
	Class client for storing files in memory Usually retrieved from components::FsCache More...
class	os_signals::Processor
	A client that allows to subscribe to OS signals SIGUSR1 andSIGUSR2`. More...
class	storages::secdist::SecdistConfig
	Client to retrieve credentials from the components::Secdist. More...
class	storages::secdist::Secdist
	Client to retrieve credentials from the components::Secdist and to subscribe to their updates. More...
class	utils::statistics::Storage
class	storages::mongo::Pool
	MongoDB client pool. More...
class	storages::postgres::Cluster
	Interface for executing queries on a cluster of PostgreSQL servers. More...
class	storages::redis::Client
	Redis client. More...
class	storages::redis::SubscribeClient
	Client that allows subscribing to Redis channel messages. More...
class	storages::clickhouse::Cluster
	Interface for executing queries on a cluster of ClickHouse servers. More...
class	kafka::ConsumerScope
	RAII class that used as interface for Apache Kafka Consumer interaction and proper lifetime management. More...
class	kafka::Producer
	Apache Kafka Producer Client. More...
class	urabbitmq::Client
	Interface for communicating with a RabbitMQ cluster. More...
class	storages::mysql::Cluster
	Client interface for a cluster of MySQL servers. Usually retrieved from components::MySQL. More...